*Feel free to discuss amongst yourselves..Issac's video was flawed since he used a mat below mortar bed which gave a false result..., I have stated my opinion on this subject many more times than I care to, I have done a demo and stated my opinion again on all the aspects of a pre slope, it's a dead horse now and I won't entertain any questions or debate the subject here*
Well, what you DONT do, is apply caulk while screwing the cap on in between, which is what I did. Ow I can’t sleep thinking that there’s a shower I built, just waiting to fail.
I love tile drama lol! All of you main guys putting out videos are awesome! I applaud you all. Being a contractor myself I don’t have the nerve to do videos so my hat is off to y’all!
That family guy clip! “That could be my favorite thing I’ve ever seen!” I love your videos, and your descriptions and explanations of what to do and what not to do are great! Currently in the process of building a 3x5 shower in a corner with a 90 degree curb, “poured” the pan last night, scraping excess and deficiencies tonight. Looks good so far, and with your shared knowledge I feel 100% confident in the work.
Thanks for your videos. After many tiling videos, yours always prove to be the most informative. You give peace of mind in areas where I feel I might have made a mistake. As a long time handyman, I just did my 3rd shower pan in 15 years. On the latest, Worried about my pre slope being enough. just put to rest.
Interesting experiment. Thanks. Most amazing part was the amount of work done inside the house. I kept expecting to hear a wife coming in the room and screaming "what are you doing in my dining room?" or something to that effect.
I've been studying all you guys for several years; you, Diblasi, Ostrum, and others. I base my common sense off of the calculations of all of your condensed wisdom. I choose to do a preslope. I don't seal the final pan top until after I've done the water test to ensure the membrane is working properly.(when you do your water test, you're gonna saturate your pan no matter what. The water is going to seep up through your drain barrel threads and weeps holes.) So after the membrane test passes, and I let it dry out for a couple days, that's when I will liquid membrane the top to seal it for the tile setting. Sure, a drain can back up and still flood your drypack,but generally speaking, all water should egress out and not backup past the p-trap. This is the process I've come to use as my ritual. I appreciate all the videos all of you make for teaching us what does and doesn't work. Keep the Info flowing!
Absolutely fascinating video, superb you proved your method is 100% the right way to do pan installations. As a plumber myself it amazes me you guys don't use ceramic shower trays , much easier , thanks again for taking the time to post the video , your a quality tradesmen👍
Very interesting! Years ago and still in my country we didn't had shower pan liner or preslope. We used construction plastic whether it black or clear and for all them Years our showers never failed! I lived in my house for 38 years on a no slope shower made with construction plastic and never go a water problem! Thanks for reiterating the old days!
Why is your country not named ??? is it classified Top Secret ? Is it because no one has asked ?? Ok, What Country did you for 38 years only use construction plastic, either black or clear. I think that the plastic is from Alien Space time. please send a photo of this amazing plastic sheeting , thanx.
I agree that the issue is not that the dry pack itself clogs the weep holes. However, isn't it possible that over time, with the addition of detergent residue, mineral deposits and perhaps mold, the mortar (in the weep holes) eventually becomes less permeable or impermeable?
Every shower I tear out with no preslope, smells terrible, which is caused by bacteria, this is my main complaint. At end of day, if water isn't leaving the pan and destroying everything, you are good(ish)
You’re the reason I tried without a preslope. The logic was there. I worked with an environmental engineering company for years and knowing how chemicals travel underground through soil and other natural (and unnatural) channels the preslope argument made sense- how could it matter if the water moved through capillary action?!? So watching this was awesome and I appreciate these videos.
Capillary action is stronger than gravity, but when complete saturation of water in mortar occurs at some point, it would seem helpful to have a slope to aid in drainage purposes.
Everyone agrees that preslope helps. what he is trying to show you is that water will pull itself out of the drypack and into the drain without preslope. Preslope is only a requiment when you are on a concrete basement floor and the floor slopes away from the drain. In this scenario in his video, the base is perfectly flat and then the liner goes up the sides so it's like a preslope of 0 which in theory will drain. But when you have the slope of the base going away from the drain now you are relying more and more on the wicking effect to pull the water up the slope and over the hump. there comes a point then the water isn't strong enough to wick itself dry because your base is sloped so bad. SO if your base is flat this video proves it drains. I am doing my shower in the basement and I found a small section that slopes away from the drain so I have to preslope because I dont want to risk it.
@@stevenferro Pre slopes are a thing of the past now a days their doing closed systems so it wouldn't matter if your foundation was off level if you do it how they do it now.. Fully water proof on pan no water should soak in your pan period..
What I do, is that once my drain is set I will use scrap pieces of 1/2 cement board and install it in the shower floor around the drain. Than mix some sand mix and do a small pre slope. Just so that I have a pitch towards the drain. I try to avoid having a big shower floor. The big step up will be a negative on my customers. What are your thoughts?
I did my tub/shower conversion about 2 years ago. I live in a 40 year old double wide. I knew I was not going to use any tile because it is so expensive that I could never recover the cost. So I planned on just a bare cement type of floor pan. The drain was forced into the right rear corner because of the structure underneath. The bath tub was 54" wide. So with the long drain path I did a pre-slope for added measure. I concluded it would not hurt and might actually help. Since there was to be no tile, the pan would be saturated regularly. The cement would deteriorate over time. So the better the drain the longer it should last. Then I ran across a product that is used to seal concrete driveways and sidewalks. I put that on it and now the water just beads up like on wax. Like putting RedGard on top of it except it is clear. Only time will tell, but will probably last longer than the double wide does.
You and Issac both have great content. I have been learning a lot from you guys and now feel like I can tackle my own shower pan. I hope one day you guys will be able to come together and collaborate because I think it would benefit all of your guys subscribers. Great stuff.
Perhaps there really is more than one way to skin a cat??? I watched both videos and still cannot make up my mind. Inconclusive. Someone mentioned in Tile Coach's video about making/using boxes made out of plexiglass. That would be definitive. To see in real-time how the water is moving and traveling. . . Gold! In this video we never quite know how much water is sitting at the bottom from the pre-soak. In the Tile coaches video he used some cover at the bottom...
@@johnsnetsinger7105 Depends on your definition of what *collaborate* means in YOUR head. Both Bob and Issac had a joint live stream event together so you can decide for yourself. Additionally, people can change their minds on certain products or techniques as more information and data becomes available. For example, the Earth was once considered *Center of Universe* and that everything circled around the Earth to appease the Roman Catholic Church and later Galileo (Italian astronomer) correctly asserted that our Earth circled around the Sun and was persecuted for it. Even Issac has now essentially stopped using the Schluter drains (both circular and the linear drain) since they have had many failures and since switched to preferring the Fx Flow drain which seems to be much better performing drain. Lastly, even Issac has said there is enough room in CZcams to have lots of tiler slingers on the platform and it is not a contest where it is either Issac or Bob.
Whether you pre-slope or not the mortar is not ever going to dry out in a shower that is in daily use. With the tile cap, water will not evaporate beyond what is held by capillary action. With tile on top and water just seeping through the grout, there will never be enough water flowing through it to wash out bacteria or mold.
I know this video is old but I just had to comment. I am an engineer but that doesn't make me an expert in this matter, however after watching this video and reading all the comments I have decided to do a pre-slope in my shower for these reasons: Here's a list of 15 obsolete home building practices in the U.S. that have been abandoned due to improved practices: 1. Copper pipe without protective sleeves: Copper pipes used to be installed directly under concrete slabs without protective sleeves, leading to potential corrosion and leaks. Modern practices use purpose-designed sleeves to protect pipes. 2. Asphalt felt paper as pipe wrap: Asphalt felt paper used to be wrapped around copper pipes, but it has been replaced with more durable and effective materials. 3. Traditional mortar for tile installation: Traditional sand-cement mortar used to be the standard for tile installations, but now thin-set adhesives are widely used for better adhesion and flexibility. 4. Lead-based paint: Lead-based paint, commonly used in the past, has been abandoned due to health and environmental concerns. Nowadays, lead-free alternatives are used. 5. Knob-and-tube wiring: This outdated electrical wiring method has been replaced with safer and more efficient electrical wiring systems. 6. Vermiculite insulation: Vermiculite insulation, which may contain asbestos, has been phased out due to health risks. Modern insulation materials are used instead. 7. Single-pane windows: Single-pane windows were once common but have been replaced by double-pane or energy-efficient windows for better insulation. 8. Traditional wood-burning fireplaces: Older, traditional wood-burning fireplaces are being replaced by more efficient and cleaner gas or electric fireplaces. 9. Flat roof construction without adequate drainage: Older flat roof designs with insufficient drainage have been replaced with better slope and drainage systems. 10. Paper-backed drywall: In the past, drywall with paper backing was common, but it has been replaced with moisture-resistant and mold-resistant gypsum board for increased durability. 11. Concrete without rebar reinforcement: Older concrete construction often lacked rebar reinforcement, which is now standard for added strength and structural integrity. 12. Traditional stucco: Older stucco formulations were prone to cracking and moisture issues. Modern synthetic stucco (EIFS) is more flexible and resistant to water infiltration. 13. Traditional septic systems: Outdated septic systems have been replaced with more advanced and environmentally friendly systems, such as aerobic treatment units. 14. Non-permeable vapor barriers: Traditional vapor barriers didn't allow proper moisture transfer, leading to moisture issues. Permeable vapor barriers are now used for better ventilation. 15. Traditional post-and-beam construction: Traditional heavy timber post-and-beam construction has been replaced by lighter and more versatile engineered wood products. These examples represent just a selection of the many obsolete home building practices that have been abandoned in favor of more improved and advanced methods over time. I do believe that the practice of pre-sloped mortar beds are just one more improvement over past practices.
While I agree a lot of modern practices are improvements ( asbestos NOT one of them, it was health reasons and not for practical reasons, as asbestos MADE things/products better ), your point you tried to make actually makes my point. From turn of last century drain systems for showers transitioned to "better" by introducing weep holes in drains which were used for 4-5 decades at least. whereas the IMPROVED shower system negates the weep hole system alltogether by implementing a sealed system, as I've done from at least 5 years ago with a liquid topical membrane & silicone at drain neck.....the so called divot system others adopted, or now with a product ( FLOEFEX DRAIN ) and sheet membrane. All 3 in my opinion work dependent on who installs, and all 3 do away with a weep hole mentality which is now antiquated anyway, which is YOUR point, out with old & in with new/improved. That being said you only have to answer to you, I must answer to a customer base should I fail, and I've had no failures in 24 years.
@@StarrTile No, I'm accountable to a higher power: My wife, my children and my guests that may use this shower. Your opinions are just that, opinions based on anecdotal empirical evidence you've gathered leading to your own conclusions, nothing more. You are an installer that chooses not to follow what's become an industry standard practice. In that respect you SHOULD be responsible to your customers. Industry "best" practice is this: "In a stall shower, the plumbing code requires the floor to be sloped one quarter (1/4) of an inch per foot in order to carry the water effectively to the drain. This slope, according to the TCNA Handbook is called “sloped fill” or commonly known as the pre-slope. This sloped material is installed under the pan liner (waterproofing membrane)." The industry best practice (TCNA) for installing a shower bed with a sand/mortar mix is to use a pre-slope. This practice has been widely adopted and recommended by industry experts, tile manufacturers, and building codes for several reasons: 1. **Water Management:** A pre-slope ensures proper water drainage towards the shower drain, minimizing the risk of water pooling and potential leaks. This is especially important in showers where water exposure is frequent. 2. **Waterproofing Enhancement:** While modern waterproofing materials are effective, adding a pre-slope provides an additional layer of protection against water damage. It helps prevent any water that may penetrate through the tile and grout from reaching vulnerable areas, such as the shower pan or the subfloor. 3. **Long-Term Durability:** A properly installed pre-slope can contribute to the long-term durability and performance of the shower. It helps maintain the integrity of the shower system and reduces the likelihood of water-related issues, such as mold growth and deterioration. 4. **Compliance with Building Codes:** In many regions, building codes require the use of a pre-slope in shower installations to meet specific performance standards and prevent water damage. That being said, it's essential to keep in mind that industry practices and recommendations may evolve over time. I too am guilty of selectively deviating from industry practices sometimes as with the trend in faucets whereby they have limiting devices to prevent scalding. I'm 72 years old and in my lifetime never have had to rely on such devices to 'protect me from myself'.... I remove them from the faucets when installing them.
I know this vid is 2 years old, but it reminded me of an experiment back in middle school. If you take a stalk of celery and put it in food-colored water, the stalk will suck up the liquid far above the lowest point of the container. It’s an easier visualization of capillary action. So no, water doesn’t always go to the lowest place.
Great Video and experimental proof, capillary action works!!! If that slab had been allowed to sit a month, like in an unrented apt, then it would have been bone dry whether the pan was level or not, capillary action trumps gravity!!! Good Job! And yes, a shower pan that is old will have a lot of smelly stuff in it due to all the tiny dead skin cells and stuff, unless it's Red Gard'd!!!
I have been a flooring professional for 30 years. You my friend are a critical thinker and what you are explaining makes absolute sense. The question now is " how saturated do you want the mortar bed to be"? You have my attention.
Wet is wet...capillary action insures all pans ( water in water out system ) will always remain wet in void of air to dry out. Going forward we all waterproof the the surface now, be it liquid topical membrane or a fleeced/clothe... Keeps any moisture out so the pan is only for a slope at surface.
@@StarrTile Im pretty convinced that keeping moisture out of the mortar bed is the answer. water needs to go directly to the drain without absorbing into surfaces period. Water needs to escape before it can gather or absorb.
@@gwynja3191 Glad someone mentioned this. I was going to suggest that Isaac, mentioned in the video, uses a membrane over the drypacked pan (please correct me if I am wrong). Wouldn't this be the best practice.? This video is very eye opening and appreciated!
@JoeySchalger @G Wyneja3 someone posted this in the comments, since you missed the entire point of his demonstration. "Everyone agrees that preslope helps. what he is trying to show you is that water will pull itself out of the drypack and into the drain without preslope. Preslope is only a requiment when you are on a concrete basement floor and the floor slopes away from the drain. In this scenario in his video, the base is perfectly flat and then the liner goes up the sides so it's like a preslope of 0 which in theory will drain. But when you have the slope of the base going away from the drain now you are relying more and more on the wicking effect to pull the water up the slope and over the hump. there comes a point then the water isn't strong enough to wick itself dry because your base is sloped so bad. SO if your base is flat this video proves it drains"
S9...I am installing or cutting into a cement floor to have the shower tile sloped into a floor drain. Can I just place a strip of pan liner around the edges up on my 2x6 backers and extend down into the pan not putting the pan liner all the way down to the drain? Of course I will be putting thin set to smooth out the cement to put the tile on. Thanks for any input
My thoughts too. Even though the bucket fills up that doesn't mean there's not water in the low spots. If the pan stays saturated it will not wick up low spot water. But I guess if you're using the shower every day, the pan will stay saturated anyway causing it to fail.? I'm concerned with water remaining in low spots and creating mold/mildew.
What Bob is saying here (not that I agree) is that since moisture is drawn from wet to dry areas is that the capillary action will soak up any standing water on the liner like a sponge, as the mortar bed drains into the weeps. As it drains from the mortar into the weeps it lowers the moisture level around the drain which draws moisture from the outlying areas up through the mortar bed (or sponge)
Just a word out there for all the Tiny House [on wheels] DIY builders -Pre slope the shower, because you KNOW the trailer supports are going to sink 😉 Great video! I like how all your videos are thinking videos. Details matter for sure & the solid pebbles blocking weep holes makes sense.
what are the dimensions of your demonstration rig? Do you think the results would be the same if it were say twice as big or three times as big? Main reason I ask is because at around 13:20 you add a quarter inch shim to one side, unless your rig is only a foot wide ( which it appears to be larger than that) then that is less than a 1/4 inch per foot, if its a 2 foot span then you are only at 1/8 inch per foot so that's the first issue I see. Second if it is 2 ft by 2ft a 30" circle would not fit inside and then it's not even a legal shower size so the whole demonstration is pretty much a novelty at that point because it doesn't accurately depict a real world situation. It would be interesting to actually do a side by side comparison like you mentioned on Issacs video. One with pre slope and lets say one with a backwards pre slope or one that is sloped to one side since we rarely find a flat and level floor in a real world situation.
When I did my first shower I did a pre slop mainly because I did not counter sink my drain like you do. So since I had to bring the floor up to the drain I did it. Like you say it couldn't hurt. But I also believe it is not necessary . Especially if the liner is installed correctly. Keep up the good work.
I do agree your point that a lot of ppl just listen and follow, they don’t even think or understand what and why they do in any particular way. Even a lot of professional guys don’t even dive to think. Don’t just listen, be skeptical and alway try to challenge with humble, this is how thing get developed. Great video!
Cool demo I’ve built upwards of 150 tile showers with no preslope no call backs Those who do a preslope I’m not saying there doing it wrong either but your demo shows no preslope is not wrong either thanks bob
@@danabennett7795 I did pvc the first 10 years of doing tile..and guess what did them all wrong no presolpes just a bunch of water holders...I can assure you presloping works.. around here the code was changed because there was so many problems with pans holding water....I'd call oatey tec support talk to those guys..look into ntca approved methods . building codes they all will tell you a presolpe is needed...and of course you can always say well star tile says it's not needed and did a test so I'm going with that..and that's your choice but and the end of the day if you're a true professional you'll do things to code and manufacturers recommendations..any thing out side of that there is nothing to back you up if you get sued .
Slope or no slope. That is the question. I've watched both videos. Both to me look fine. But if I was to err on the side of caution, I would put in a preslope. Just for peace of mind.
I do that..so yeah it makes the experiment a moot issue. But you need to be sure the Redgard is worked in at the drain good so no water gets in pan, a bead of silicone before waterproof too
Thank you Bob, I’m converting my tub to shower on concrete slab, and will apply a few coats of waterproofing on the mud base before laying the tiles. Keep these videos coming.
The thing I see, is the pre-slope (just like the no slope) requires 100% saturation to work. Both you and Issac showed that. But if just one cup of water was put in at random all around, how much would leak back out? Putting on a layer of tile with the correct grout (by a professional, not an amateur like me) means almost no water will get in. Yes grout is porous, but done right it would only be "dampness" that SLOWLY gets through. All the shower water will run over the surface and down the drain. Like you said in your 2014 video, for the water to be able to actually run down a slope while covered in mortar/dry-pack it would have to be absolutely saturated and if THAT much water is under the tiles, then something is badly wrong and the entire shower floor will need to be torn up because grout and thinset will start crumbling.
if your applying a mud shower pan to a concrete slab floor do you still need a Oatley liner? or could you just put three coats of red guard over the top of the mud pan then tile over it?
Awesome video. Never did use peples around the drain. If water can get through the mortar to the painliner, I always thought it could get through the mortar in the weep holes. Prepitches are required by code here in Florida.
Hi. I am planning to build a walk-in shower on the concrete floor. Would it be ok if I build a slope right on the concrete floor (no pre-slope) and not using the pan liner at all? I plan to use red guard on the slope before laying the tiles. Do you recommend this method? Thanks.
Does the mortar adhere to the rubber underlayment like glue after it dries? Or after the mortar dries and shrinks a little, would it be possible for some space or gaps to occur which then the pre slope would always be aiming that residual water back into the drain?
I have built many pre slopes using 22/32 plywood cut to fit over the shower sub floor. A 3/4 riser at the outside and 2” drywall screws around the hole cut to clear the drain will provide an almost perfect slope to the drain. Good demo, thanks man!
I have seen guys do it with ¼ cement board, blocked up at the outer edge, and screwed into the floor at the center, with thinset to the up the slope under it.. the screwed once that's set. I'm not brave enough to try it, but it's clever, if nothing else
Hi there. Thanks for your videos. I have a question regarding the demo of an existing shower pan on a plywood floor and whether you can reuse the same drain assembly (upper and lower flanges plus the drain barrel) after demo? I am assuming that the subfloor will be sound. Do you generally replace every drain when you demo an old shower pan? What is common to expect?
I would never entertain using the same drain assembly that you are taking out, Only Exception is if it was just installed last week or last month where I know it's pristine, I always replace the whole drain assembly including the P-trap, but that's just me
wow Ive always done a pre-slope but I think Im convinced, I will definitely try to avoid doing them. Water always finds a way I guess. still its the Gravity pulling water down creating a drier area near weep holes and that drives the capillary action .
to my understanding, you said the soapy shower water deteriorates the sand-mortar mix. It deteriorates the cement components and leaves the sand behind. So anytime water gets into the mortar mix is bad? Is this correct? or is it ok for the mortar mix to get saturated? I realize that you use thin set around drain and you mention it helps the redguard waterproofing to adhere better. that was said in another video of yours. then you coat with redguard. This is to ensure that water never actually enters the mortar bed but it is there as a backup? This is my understanding of the video, am i understanding correctly? This is very helpful to me.
I posted this over at Isaac Ostrum video comments and curious what your thoughts are? A Case for Non-pre slope Just being the devils advocate here. First off I always put a pre-slope in my work due to avoiding any future liability but I don't think it's as important as we make it out to be. We need to keep in mind that the porous deck mud acts like a huge monolithic coarse sponge. Any monolithic material composition with particle sizes below 0.100" or less than 1/8" will have capillary action and will hold a "perched water table" at a certain level. I don't know what that level would be for deck mud(would be a great experiment as well) but it's there even if i't a 1/4". In a gardening container pot with the average potting mix you could have a perched water table as high as 3". An example may help. If you soak a long sponge in a bucket then hold it vertically letting the excess freely drain out and let stand for a while you will notice that the top is quite moist but if you squeeze the bottom then water pours out. That's the perched water table. Even with no pre-slope there is never any "standing water". I have never found much "standing water" in these demos. There may be some free water but it's mostly due to large cracks losing it's monolithic structure and or a large negative slope but not directly due to no pre-slope on a flat floor. Any water higher than the PWT is drained out of the weep holes. Moisture above the PWT is held tightly to the particles by capillary adhesive forces.
I appreciate your insight at explanation.. Perhaps others will benefit by it. It is interesting to me that you are the fourth person to comment that you do a pre slope in order to avoid liability, I have yet to pull out a saturated smelly shower, or even one that had cracked from the constant water presence that was less than 5 or 10 years old, most have been in excess of 20 years plus that were Builders grade and many of the things were done incorrect. If I ever thought that not having a pre slope would lead to a failure in a year or two then I would definitely be on board to do them, it is just not the case
I’m working with a Schluter pre slope offset pan. I’m laying 4x8 tiles for the shower floor which is a lot bigger than the 2x2 they recommend due to how the pan slopes. Without doing relief cuts or risking lippage, could I more or less lay these flat?
4inches by 8inches right ?? Not 4'x8'😂 However you work those out you would need a positive slope to the drain even if that means doing angle cuts symmetrically on the tile
OK guys. First I'm not a tiler, remodel expert, builder. I am however a stickler for doing things right regardless what anyone wants to do. In my opinion both of you are right. I've watched both of you do your thing and you both seem very competent and skilled. I like watching Bob, no offense Eric. Bob states he is in this video thing to help people like me figure out what to do and what not to do. He takes time in his videos to explain (sometimes twice or more) what he did and why he did it that way. Makes perfect sense to me. He works alone running his own business and I expect being in Atlanta has more work than he wants, perhaps not. Regardless if where you live and work requires a permit and strict adherence to building codes then you do what you have to do. If you are reputable and do good work, back up your work with your reputation then you should never have a situation where the client is "out to get you". Now some might say that those building and zoning people don't know crap. Well, they are the customers best hope of making sure his job gets done according to some else's guidelines and requirements thereby keeping professionals or semi professionals honest. In Georgia, where Bob and I both reside, there are way too many folks out there running around claiming to be something they're not. Which makes finding a pro somewhat difficult because ultimately the customer really doesn't want to pay anymore than a fair price for quality work and materials. Eric, You run your own business with employees, that means you not only have keep track of what you are doing but what they are doing as well. I'm not advocating that your folks are not trustworthy or skilled in what they do, but I do know first hand that "when the cats away, the mice will play". I've learned alot in my sixty nine years on this planet and I am proud to say alot of it was because I pay attention to detail, after all the beauty of any job done right is all in the details, Bob pays alot of attention to details and makes that clear in his videos. I have a small project I am considering right now, I know how to get started, but if things go badly or not I am working with obsolete no longer made tile. So I may call you Bob. Good luck to you both, I just had to chime in. It's my opinion and I'm sticking to it.
waterproofing your mud pan, does it effect the adhesion of the thinset at all? and with no pre-slope, what stops the pan liner from shifting? just the weight of the mud bed?
If it affected that he's in process I wouldn't be doing it so the answer would be no, and yes the weight of the mud bed stops movement, typically 150 lb to 200 lb plus of material
@@StarrTile your videos are great, I love the fact that your willing to help and answer questions- I dont see the need for a mud pan under the liner myself, and greenboard is great, logically makes total sense to use for walls, but people freak out when they see or hear it
Don't know if I thinking cornetly... If I do preslope and than read guard on the top than slop... Than if Wather penetrate slope.. Stop on read guard and goes down cuz preslope... Right? His with out preslope Wather gonna stay somwhere in lower spot... Please explain Thx
Thanks for the experiment. Since you saturated the pan before the final test, all of the water came out since by definition, a 'saturated' pan cannot hold any more water. What we don't know is how much water did it take to saturate a flat pan vs a pre-sloped pan. And as Isaac says, is there a puddle in a corner that might have held less water if there was a pre-slope. And maybe a pre-sloped pan would drain in less than the 12 min it took for yours to drain. Just continuing the discussion. By the way, there is gravity all through the pan and the mud; it's just that capillary action can overcome the gravity for a portion of the water.
@@user-xt1vs2oz3b Yes I agree. If you had a low spot in the pre-slope ( or no slope ) it could have been 100% saturated in those areas. I think it's over saturation that breaks down the deck mud. The deck mud turning to sand is from it being over saturated for an extended period from clogged weep holes. So those low spots with no pre-slope will turn to sand before long, it's not from shampoo.
Isaac's video was a scam..he used troba mat, that is used in landscaping not in showers, if you try to use that mat in a shower you would have a complete utter failure
@@StarrTile i am not sure i have seen the video you referenced. But i have seen lots of his videos and think he does good work. His tests definitely do inspire one to ask questions which is always a good thing. I am by no means an authority as far as tile goes, but do work with tile everyday and recognize he does quality work. First of your vids i had watched. And while i wont tell you you are wrong, i have torn out quite a few that were 50 plus yrs old and bone dry.
The mock-up of the shower pan that he did, use a mat that is not used in showers to get a foregone conclusion results from that video, he knew water would come out at a quicker Pace than my video if you use that Mat, that was cheating and he knew it. I'm not taking away from his skill-set but having at least five or six videos of failures tells me something about his build methods.. that he goes back to fix them and then makes excuses as to why they failed oh, it's never his fault... I personally would not hire any professional knowing that they have a failure rate like that. Even mistakes that I have made on a job are rectified while I'm there, I've never gone back on a job as he has years later. He provides some good information but he is also too much of a book Soldier that can't think outside of the box, another issue that I have with him but wherever you can get your information the more the merrier 👌👍
@@StarrTile i do feel ya there. Havent had too many/ any where i have had to return. But hate to say never and jinx it. I must admit, i dont do as many showers as i used to as i do more commercial these days. But you are correct in that i do usually try to fix mistakes before i leave for good lol. Anyhow, wasnt throwing shade. Just saying i had seen his stuff and it looks like he does respectable work.
Pre-slop or not pre-slop? I am remodeling my own bathroom and this question got me puzzled all over. Could not get to point why should I do this sandwich, so went to no pre-slop. But very pleased to find discussion here on this topic, that helped me finally to get to the point why many care for pre-slop. 1: Let water to get out from low spots in top layer of mortar. 2. To avoid liability. Thanks so much for this clarification! But I am not about to redo none slop pan that I already did. Just curious, I painted the the top layer with waterproofed paint, what difference it might make? Also I painted under the liner all the sides of the shower to prevent from tiny ants coming because I saw them under old pan when removing it. Those beasts are the nuisance in FL and they get to any place in the house where they have enough moisture. The shower is one one of them and I wonder that no one is offering the way to fight those creatures.
My thing is , everyone uses silicone to seal your liner to the drain itself. How do you guys think the water will exist under the liner if its sealed to the drain?
Thank you for all you work you putting into you videos. As to the test: You could have done a simpler test. Do not install mortar and pre slope at all. Just have that PVC liner. Once you pour water first time (what you did with pre saturation) you will see puddles of water on PVC. After that no matter how much water you add you will have same puddles and the same amount of water going in and out at the end. If you will have only pre slope you will not have puddles . So pre slope will not allow pockets of staying water in the mortar. And for capillary action magic in the sand: If you are on the sandy beach next to the water and start digging a hole in the dry sand you will get puddle of water eventually - close to the water level of the lake/ocean/river. Puddles (pockets of water) may stay in the sand even if the surface is dry.
This is on point. So if there was standing water or water that got in under the tile through the redguard, there would be puddles without a pre-slope and no way for water to evaporate out if the top was sealed. This will cause mold and rot. So always pre-slope and never add two layers of waterproofing (liner and redguard). That is just a recipe for disaster as the water will be trapped. You always want to have only 1 layer of waterproofing and let it dry out to one side or the other.
@jc5543 your method you describe was done for last 40 years or longer, we aren't doing that anymore...welcome to 21st century and sealed systems, mine is redgard, Aqua defense, hydroban, or some other liquid topical membrane, other people's method would be sheet membrane attached to the surface of the mortar, still sealed system. My Redgard won't fail 100% so your sky is falling hypothetical holds...hmmm...no water 🙃
I had a guy do a mud pan and tile for me about 3 years ago. Recently I re-grout the perimeter of the floor and I accidentally broke a corner of the wall tile when I removed to fix it I could tell there was lots of moisture in the are behind that corner. So knowing the bed is going to get wet how do I know if it needs to be torn out and redone or if it’s ok and not worry about it. It’s a nice looking shower and I would hate to redo the whole shower. Thank you!
I don't know why but every tile guy proposes to do 100-year shower, but the reality is everything has a shelf life in your house and eventually the shower needs to be redone, probably 25-30 years down the road. Then again there is not a monolithic way to build a shower so there's always operator malfunction, that you had an issue 3 years after the fact just shows his lack of knowledge, the surface should have been waterproofed. But my Mantra is if it's not broke then don't fix it
If a serious amount of water is getting to your mortar won’t it just absorb it and slowly weep it out regardless of whether it is pre-sloped or not? Unless a small amount of saturation in the bottom of it somehow damages the drypack it seems the pre-slope is more of a precaution against a poorly or improperly installed pan-liner making it pointless if it was installed correctly in the first place. Just my two cents.
The only real advantage to having a pre slope is if your subfloor is off-kilter and you don't Rectify that before the pan material, then a pre slope would benefit you
I have had second thoughts about this matter. If a small leak was to happen in the bottom of the pan were the first water collected then that water would RUN OUT the leak and then that water would be topped up by the next shower, repeatably. With a preslope all water would run out and only a minor amount of water would be available to leak through. So if that is true then the matter to be faced is if anything goes wrong with the pan liner install then the potential damage below is minimised. With a flood test the water pressure above would push down on the pan liner minimising leak flow. the empty tile bed would not exert the same sealing pressure. So both tests work but the long term out come from the failure of a less skilled installer may be minimised by the preslope. I am about to do a second bathroom, the first i did years ago without any water proofing on a ground slab with a slope to the outside. I 'lucked out', no damage inside. I just followed the old trady's advise at the time. This time upstairs no mistakes.
I thought the pre-slope was made for underneath the liner so the water would run down the liner into the drain if there is a leak ... am I wrong? Would a slope not help in this case?
Jeremy Aitken The other gentleman that he mentioned did the pre-slope experiment. This video was his response doing a non-pre-slope experiment. “Get it”?.
Exactly what I was thinking. If you pre-slope before the liner the correct way, you don’t get any wicking. It will just be a sloped liner instead of a flat or level liner.
It's called condensation. It does get damp but since the area below is dryer the subfloor moisture can wick to the dryer area. But this is definitely not good for OSB or plywood over time.
I can understand the wicking action that occurs but are you thinking that the floor below the liner doesn't need to be at least level in the entire shower floor space because the cap action will absorb the water and then gravity at the drain weep holes give the water the pathway to get out? If so why worry about the drain base being flush with sub floor?
Yes in an ideal world you would have your floor flat and level, but then again your bottom flange where your weep holes are and troughs that are cut out of the drain are only a quarter inch high so the most water you would ever have to pool would be a quarter inch at best and that's not going to stay stagnant because it will wick up through the rest of the mortar which arguably is plus 200 pounds, having said all that we are not doing the in and out system anymore we are waterproofing the entire surface so the whole wicking action and pre slope and all of that is a moot issue
I do not use pebbles and use the plastic disk too. So I agree on the point. Although the issue with no preslope is to help water from pooling in the corners of the pan or the low spots. This video shows those low spots. Now the issue is mildew growth. I have seen it on ALL non-presloped pans. All the corners will have mildew growth from under the tile and can never be removed. All of the presloped pans do not have this issue. Sure not using a preslope is easy, drains 90% of the water, but mildew growth in the grout lines is a major issue with this. This video is a prefect example of water pooling in the pan. All the water would have drained if there was a preslope going all the way to the drain. The mistake is Starr just props up the edge of the pan not the whole pan.
Would an alternative pan method be sloped mortar base(no membrane) with a recessed non weep hole drain, coated with two or more coats of Red Guard with the coating continuing up the walls. Would this be the same as Custom Products preformed foam shower bases with Red Guard (but much more inexpensive)? Would the sealed mortar base trap moisture between the tile and the base, and create smelly mold and mildew? For a shower used daily, is mold and mildew an issue regardless of the pan system used? I wonder if a daily used shower pan ever dries out during its lifetime? Finally, does all the controversy over shower floors make preformed acrylic and cast iron pans the ideal shower floor? Great video...thanks for taking time to demonstrate capillary action of water!
I am **totally NOT** sold on the premise that no pre slope in needed. Goes against everything I was ever taught by numerous installers/contractors. Gravity is what governs where water travels. Period. Yes capillary action exists but gravity still directs it. Drive or hike up any river or creek bed and watch nature work. Then paddle down it in a kayak if you have the skills. I agree with much of Starr Tile's logic and his demonstration, and all... But will always include a pre slope element to avoid allowing any possibility of water finding a spot to pool up and hang out. These days with paint on waterproof membranes I fully coat the top surface of my shower pans (Hydroban), usually 3 coats to be sure to get the required thickness. Also I coat the subfloor and the pre slope. I end up with a layer cake which I believe strengthens the entire pan and keeps water from the mortar bed. So after it penetrates grout/thinset layers it hits membrane and is inclined to follow slope to drain. I agree it percolates through daypack just fine through weep holes and other egress points of drain assembly. But I see no reason to exclude slope from the equation based on this video.
Can I ask, the major thing I see different between you and other shower guys is you waterproof UNDER the mortar bed. Many others do the bed right on the slab or plywood subfloor, and then they waterproof overtop with membrane or whatnot and many of them NOW (after I presume watching you) they almost all apply a waterproofing like redguard or it's equivalents ontop of that. If the redguard or whatever is the end all why do the waterproofing under the bed? I've even seen you use membrane instead of a liner on tricky showers before your mortar bed. I'd like to see that test, do you need to waterproof under your mortar bed. I suppose in the end if all else fails it's one final redundancy but you tend to shy away from that besides this.
Suppose the subfloor isn’t level, it’s 1/4” lower at the curb than in the center at the drain. Would you not worry about water collecting at the curb? Or would you make sure do level the subfloor at the start before you do anything else?
StarrTile Okay, makes sense, especially after the results of your experiment. Another question: Oatley says (in their instructions that come with the liner if you buy the pre-cut roll) drill a 4-1/2” hole for the drain and set the drain on the four legs of the bolt mounts on the sub-floor, leaving about 1/2” from subfloor to top of drain top. This gap is filled in with the pre-slope. So this method would provide more support for the drain if someone heavy stepped down on the center of the drain. I don’t know what Sioux Chief says about installing their drains. Also if different methods should be applied to pvc vs abs?
PVC and ABS are basically the same. There's no issue with "weight on drain" if you use the bolt recess or not, it doesn't work that way. The support comes from many sources including strapping the p-trap to begin with. Oatey's video shows many things done wrong, as far as building a shower...do whichever way makes sense to you.
@@CreationVibration You are misinterpreting the Oatey instructions for correctly installing their drain. To start with you are correct, they say to drill a 4 1/2 inch hole to set the drain on.......... Guess what? The diameter of the four legs or bolt mounts is 4 1/2 inches. There is no way that will sit on the bolt flange. The cut away diagram from Oatey shows the drain sit flush on the flat underside of the drain. Secondly, I called Oatey for verification and they told me, yes you arereadin the instructions correct..... the drain should sit flat on the flange underside.................... NOT on the 4 Bolt Housings leaving the drain leaving it to sit up about 1/2' off the subfloor. Wrong!!!
Interesting video. But wouldn’t having no slope at all cause some water to pool on the shower floor without any way of being evacuated other than through evaporation?
Wicking action would ensure that your pan would be wet all the time, the fact that there is no gravity because you're dealing with a mortar bed that gets saturated would not allow water necessarily to pull anywhere, all that being said it's irrelevant now because we waterproof the surface and thereby the mortar never gets wet
Love your videos, so thanks for sharing your knowledge! Can you tell me if my thinking is right with this approach: Using a Flo FX type drain without weep holes makes the pre slope totally irrelevant, , right? My approach is: 1) tar paper/plastic sheeting right over the plywood substrate; 2) staple metal lath; 3) build mortar shower pan with the right pitch with Flo FX installed; 4) install waterproof membrane like Kerdi or liquid waterproof barrier like Red Guard, Hydro Ban, etc. over the mortar pan; 5) install floor tile. No need for the 40mil plastic liner in this case since the waterproofing is happening on the top of the pan, right?
Yes suppose your way would work... there are many many ways to do the right thing as long as it doesn't leak at the end, I don't necessarily agree with doing it for a customer because I don't want to toss people failure. Having said that I waterproof the surface of my pan so it also makes the pre slope obsolete... and I don't need the flow drain for that
awesome video.... so I saw a video of you applying Red Guard... is this where I would apply it ? onto the mortar ?and then after 3 layers.... next is thinset for tiles ?
@@StarrTile would also like to ask you about the type of grout to use on floor tile in the shower floor. should we be using epoxy grout or something else ? TIA
If water gets into your mortar bed which is mortar then how is it that it cannot get into your clogged weep holes that are clogged with mortar, irrational 😂
May Take 12 minutes without slope maybe with slope take 6 minutes byw u are a great tile master I like see a nice work done bcz i know isn't easy task to complete without years and years on real work field I know what's I talking about bcz I'm a plumber after 25 years I still learning from other trademan 👍
So those 60 Lb with the green strip,do they have Sand in It??I m confused 🤦♂️🤦♂️.Do you buy a separate bag of Sand and mix together?Big fan of u here.Thank you.
Sand mix..aka mortar....4-1 sand/cement. The yellow bag with a green stripe tries a little slower so you can manipulate it the next day a little bit, the yellow bag with red stripe dries quicker and you cannot manipulate
I still believe the preslope will allow more water to find its way out , however i am going to waterproof my shower beds to reduce the amount of water that makes it into the shower base, and hopefully reduce mold build up under the floor tile
A pre-slope is not a code everywhere, depends on your city, your county, or your state, in the state of Georgia I have never ever encountered a pre-slope. It is also outdated since we are doing the sealed system and not a water in water out system any longer but codes still linger for years
I learned to mortar the shower with slope without the clamping collar on . Then install a shower pan. Then idk what the tile guy does after that. Which makes sense, like a water slide to the drain.
Everyone waterproofs their shower nowadays, including the pan surface....so no water gets into pan, so preslope for what reason exactly ??? 😂 Gotta think about things rationally
If your floor is perfectly flat you do not need a preslope. This video is like a preslope setting of 0. A perfectly flat base makes it very easy for the water to wick it's way to the drain. Also, since your liner is a few mm thick, when it meets the walls it slopes upwards (there is a curve at the 90 degree) so technically there no negative slope or opposing slope in the pan. it's basically a bucket on a flat floor. If you install the liner nice and tight and your floor is flat there is no reason why it shouldn't drain. You need to preslope when your base is not flat, like the concrete in your basement is built poorly, or when the carpenters build the floor poorly. Or even if there is a very small slope in the overall floor of the washroom. if some of your shower base slopes away from your drain or if the entire floor drains to one side, then you are relying on the wicking power to pull the water up the opposing slope and then into the drain. There will be a point where the wicking power is not able to pull the water up the opposing slope. the wick power is directly related to the size of the pour spaces. the smaller the pores the stronger the water can pull. Wicking is due to the water molecule being di polar. when the negatively charged oxygen in the water molecules come into contact with other negatively charged oxygen elements in the other water molecules they push away from each other. Same goes for the 2 hydrogen elements because ++ push away from each other and same goes for --. when they hit other H's in other molecules they push away from each other. You don't see anything happening at a depth but on the surface of water you can see the effect of the collisions because they are not balanced by other molecules. So the top layer of water doesn't have water on top of it to balance out the o's and the H's pushing off each other so it makes skin like behavior. insects walk on water because of this. A miniscus forms at the edge of your glass because of this. Unbalanced water molecule collisions are pushing the water up the the side of your glass. This happens at every interface between water and air. there's an unbalanced effect. When you dip a napkin in a glass of water you will see the water rise up the napkin because of the energy that the collisions are creating at the air/water interface. The smaller the pores the higher it will rise because the energy has to carry less weight. larger pore spaces means a larger amount of water needed to fill the pore which is heavier. So the size of the poor spaces in the dry pack can only pull water up a certain amount. If your base is ever poorly sloped then there's a chance that the wick can't drain the drypack. This action also works horizontally, if the water falls into the drain then the pore spaces next to the drain have air in them and the pores adjacent to those pores are full of water so it pushes in that direction. So a flat surface like this experiment, a 0 slope will work. if you are ever uncertain, just preslope it and don't risk it. great video.
So you measure a 1/4in at the end of a 2ft level and call that correct. You just said there should be 1/4in slope per 1ft length. So should you not have 1/2in at the end of the level.
The long answer is because it hasn't been proven to work which gets into a lot of detail, the short answer is we waterproof our pan surface so preslopes are a moot issue now
I suggest we do comparison experiments for saturated pan with/without pre-slope to see if there is a difference in the amount of new water that replaces old water. First let's use water with certain concentration of ink to saturate both shower pan mud beds, then use clean water to 'wash' the mud beds to see if there is a difference in the color of water coming out of both mud beds...
That's a great idea and an experiment like that would be the only way to truly know if water is cycling. Having said that it's a moot issue because everyone waterproof their pan surface now so no water gets in to begin with
I appreciate the effort as much as anyone else but people should realize neither of these tests actually prove anything. Doing science is hard. One of the most important parts is having peers poke holes in your methodology. Here we have one test essentially testing the vaiability of a funnel. A plastic funnel with mud on top. Of coarse it works and you'll get all your water back. But that's not what your testing. Your testing whether its necessary over a non sloping funnel with mud on top. To that end it tells you nothing. On the other hand you have the non slope plastic funnel. That was saturated before hand. Look, its not exactly a huge leap to realize that there is no other possible way for this to end then to get every ounce of water back. That is what saturating is. 100% of the space that could be filled by water..... is filled by water. Where else could it go? You could've built big pools under the mud and you'd get the same result. You've already filled the mud and dead spaces with water (the fact that there probably wasnt any low dead spaces is irrelevent. If there was they would've been filled little pools with the same end result.) Neither addresses the actual issues. Im not trying to be a pro skeptic here but the issue is a lot more nuanced and difficult then this. As much as I loved mythbusters their methodology had the same issues. It wasnt science. It was just science influenced experiments. You could literally spend 4 years majoring in the ways experiments can be conceptually flawed. Researchers still get disgraced to this day by having their methods shown to be subject to basic biases.
I agree with this statement :) in the end there maybe a small influence of slope (gravity) if there are pools (gaps) in the stratum but its likely quite small. Since the influence of slope would be to increase the speed of the capillary action and time is not part of the experiment in a meaningful way... I am not a professional, so feel free to ignore my comments. I am a DIY, with my own bathroom remodel :) My take away is - slope the pan to assure efficient draining, redguard the pan to reduce influx to the pan, choose/maintain low permeating wall board, tile and grout.
*Feel free to discuss amongst yourselves..Issac's video was flawed since he used a mat below mortar bed which gave a false result..., I have stated my opinion on this subject many more times than I care to, I have done a demo and stated my opinion again on all the aspects of a pre slope, it's a dead horse now and I won't entertain any questions or debate the subject here*
Well, what you DONT do, is apply caulk while screwing the cap on in between, which is what I did. Ow I can’t sleep thinking that there’s a shower I built, just waiting to fail.
It's all in the book preslope is always required
Laces out
I love tile drama lol! All of you main guys putting out videos are awesome! I applaud you all. Being a contractor myself I don’t have the nerve to do videos so my hat is off to y’all!
That family guy clip! “That could be my favorite thing I’ve ever seen!” I love your videos, and your descriptions and explanations of what to do and what not to do are great! Currently in the process of building a 3x5 shower in a corner with a 90 degree curb, “poured” the pan last night, scraping excess and deficiencies tonight. Looks good so far, and with your shared knowledge I feel 100% confident in the work.
Thanks for your videos. After many tiling videos, yours always prove to be the most informative. You give peace of mind in areas where I feel I might have made a mistake.
As a long time handyman, I just did my 3rd shower pan in 15 years. On the latest, Worried about my pre slope being enough. just put to rest.
Interesting experiment. Thanks. Most amazing part was the amount of work done inside the house. I kept expecting to hear a wife coming in the room and screaming "what are you doing in my dining room?" or something to that effect.
I've been studying all you guys for several years; you, Diblasi, Ostrum, and others.
I base my common sense off of the calculations of all of your condensed wisdom.
I choose to do a preslope. I don't seal the final pan top until after I've done the water test to ensure the membrane is working properly.(when you do your water test, you're gonna saturate your pan no matter what. The water is going to seep up through your drain barrel threads and weeps holes.)
So after the membrane test passes, and I let it dry out for a couple days, that's when I will liquid membrane the top to seal it for the tile setting.
Sure, a drain can back up and still flood your drypack,but generally speaking, all water should egress out and not backup past the p-trap.
This is the process I've come to use as my ritual.
I appreciate all the videos all of you make for teaching us what does and doesn't work.
Keep the Info flowing!
Absolutely fascinating video, superb you proved your method is 100% the right way to do pan installations. As a plumber myself it amazes me you guys don't use ceramic shower trays , much easier , thanks again for taking the time to post the video , your a quality tradesmen👍
Very interesting! Years ago and still in my country we didn't had shower pan liner or preslope. We used construction plastic whether it black or clear and for all them Years our showers never failed! I lived in my house for 38 years on a no slope shower made with construction plastic and never go a water problem! Thanks for reiterating the old days!
Why is your country not named ??? is it classified Top Secret ? Is it because no one has asked ?? Ok, What Country did you for 38 years only use construction plastic, either black or clear. I think that the plastic is from Alien Space time.
please send a photo of this amazing plastic sheeting , thanx.
I love this guy he speaks alot of trash then ends up backing it up unlike 99.99% of tile guys keep it up 👍🏼 your the best !
I agree that the issue is not that the dry pack itself clogs the weep holes. However, isn't it possible that over time, with the addition of detergent residue, mineral deposits and perhaps mold, the mortar (in the weep holes) eventually becomes less permeable or impermeable?
Man i love these mockup videos. I've been lied to my entire life! lol I even used those rocks around the drain to keep the weep holes open! Lol
I loved seeing this to show the silliness of pebbles. It makes the permeability of mortar bed perfectly clear!
Every shower I tear out with no preslope, smells terrible, which is caused by bacteria, this is my main complaint. At end of day, if water isn't leaving the pan and destroying everything, you are good(ish)
You’re the reason I tried without a preslope. The logic was there. I worked with an environmental engineering company for years and knowing how chemicals travel underground through soil and other natural (and unnatural) channels the preslope argument made sense- how could it matter if the water moved through capillary action?!? So watching this was awesome and I appreciate these videos.
I agree with you and have watched a lot of you videos thank you for all the great info. You helped me so much building my first ever shower
Capillary action is stronger than gravity, but when complete saturation of water in mortar occurs at some point, it would seem helpful to have a slope to aid in drainage purposes.
If it gets fully saturated, then you have a bigger issue than not having a pre slope.
Everyone agrees that preslope helps. what he is trying to show you is that water will pull itself out of the drypack and into the drain without preslope. Preslope is only a requiment when you are on a concrete basement floor and the floor slopes away from the drain. In this scenario in his video, the base is perfectly flat and then the liner goes up the sides so it's like a preslope of 0 which in theory will drain. But when you have the slope of the base going away from the drain now you are relying more and more on the wicking effect to pull the water up the slope and over the hump. there comes a point then the water isn't strong enough to wick itself dry because your base is sloped so bad. SO if your base is flat this video proves it drains. I am doing my shower in the basement and I found a small section that slopes away from the drain so I have to preslope because I dont want to risk it.
@@stevenferro Pre slopes are a thing of the past now a days their doing closed systems so it wouldn't matter if your foundation was off level if you do it how they do it now.. Fully water proof on pan no water should soak in your pan period..
What I do, is that once my drain is set I will use scrap pieces of 1/2 cement board and install it in the shower floor around the drain. Than mix some sand mix and do a small pre slope. Just so that I have a pitch towards the drain. I try to avoid having a big shower floor. The big step up will be a negative on my customers. What are your thoughts?
I did my tub/shower conversion about 2 years ago. I live in a 40 year old double wide. I knew I was not going to use any tile because it is so expensive that I could never recover the cost. So I planned on just a bare cement type of floor pan. The drain was forced into the right rear corner because of the structure underneath. The bath tub was 54" wide. So with the long drain path I did a pre-slope for added measure. I concluded it would not hurt and might actually help. Since there was to be no tile, the pan would be saturated regularly. The cement would deteriorate over time. So the better the drain the longer it should last. Then I ran across a product that is used to seal concrete driveways and sidewalks. I put that on it and now the water just beads up like on wax. Like putting RedGard on top of it except it is clear. Only time will tell, but will probably last longer than the double wide does.
That sounds like a great plan, and I'm glad it's working so far !
Great video Bob, the demonstration was very interesting and well explained.
You and Issac both have great content. I have been learning a lot from you guys and now feel like I can tackle my own shower pan. I hope one day you guys will be able to come together and collaborate because I think it would benefit all of your guys subscribers. Great stuff.
Perhaps there really is more than one way to skin a cat???
I watched both videos and still cannot make up my mind. Inconclusive.
Someone mentioned in Tile Coach's video about making/using boxes made out of plexiglass. That would be definitive. To see in real-time how the water is moving and traveling. . . Gold!
In this video we never quite know how much water is sitting at the bottom from the pre-soak. In the Tile coaches video he used some cover at the bottom...
They will never collaborate because Isaac does it right and this guy does not.
@@johnsnetsinger7105 Depends on your definition of what *collaborate* means in YOUR head. Both Bob and Issac had a joint live stream event together so you can decide for yourself. Additionally, people can change their minds on certain products or techniques as more information and data becomes available. For example, the Earth was once considered *Center of Universe* and that everything circled around the Earth to appease the Roman Catholic Church and later Galileo (Italian astronomer) correctly asserted that our Earth circled around the Sun and was persecuted for it. Even Issac has now essentially stopped using the Schluter drains (both circular and the linear drain) since they have had many failures and since switched to preferring the Fx Flow drain which seems to be much better performing drain. Lastly, even Issac has said there is enough room in CZcams to have lots of tiler slingers on the platform and it is not a contest where it is either Issac or Bob.
Whether you pre-slope or not the mortar is not ever going to dry out in a shower that is in daily use. With the tile cap, water will not evaporate beyond what is held by capillary action. With tile on top and water just seeping through the grout, there will never be enough water flowing through it to wash out bacteria or mold.
So then, how do we prevent this from happening? Redgard the top of the mortar pan?
@@goskidmark I would. Either that or you could also use one of the other products like the kerdi or something.
But you can red guard the dry pack ! 😉👍🏼
Mold will not grow on mortar. Nor will it grow anaerobically.
Get a preformed pan. End if story.
Thank you for going through the trouble. Amazing
I know this video is old but I just had to comment. I am an engineer but that doesn't make me an expert in this matter, however after watching this video and reading all the comments I have decided to do a pre-slope in my shower for these reasons:
Here's a list of 15 obsolete home building practices in the U.S. that have been abandoned due to improved practices:
1. Copper pipe without protective sleeves: Copper pipes used to be installed directly under concrete slabs without protective sleeves, leading to potential corrosion and leaks. Modern practices use purpose-designed sleeves to protect pipes.
2. Asphalt felt paper as pipe wrap: Asphalt felt paper used to be wrapped around copper pipes, but it has been replaced with more durable and effective materials.
3. Traditional mortar for tile installation: Traditional sand-cement mortar used to be the standard for tile installations, but now thin-set adhesives are widely used for better adhesion and flexibility.
4. Lead-based paint: Lead-based paint, commonly used in the past, has been abandoned due to health and environmental concerns. Nowadays, lead-free alternatives are used.
5. Knob-and-tube wiring: This outdated electrical wiring method has been replaced with safer and more efficient electrical wiring systems.
6. Vermiculite insulation: Vermiculite insulation, which may contain asbestos, has been phased out due to health risks. Modern insulation materials are used instead.
7. Single-pane windows: Single-pane windows were once common but have been replaced by double-pane or energy-efficient windows for better insulation.
8. Traditional wood-burning fireplaces: Older, traditional wood-burning fireplaces are being replaced by more efficient and cleaner gas or electric fireplaces.
9. Flat roof construction without adequate drainage: Older flat roof designs with insufficient drainage have been replaced with better slope and drainage systems.
10. Paper-backed drywall: In the past, drywall with paper backing was common, but it has been replaced with moisture-resistant and mold-resistant gypsum board for increased durability.
11. Concrete without rebar reinforcement: Older concrete construction often lacked rebar reinforcement, which is now standard for added strength and structural integrity.
12. Traditional stucco: Older stucco formulations were prone to cracking and moisture issues. Modern synthetic stucco (EIFS) is more flexible and resistant to water infiltration.
13. Traditional septic systems: Outdated septic systems have been replaced with more advanced and environmentally friendly systems, such as aerobic treatment units.
14. Non-permeable vapor barriers: Traditional vapor barriers didn't allow proper moisture transfer, leading to moisture issues. Permeable vapor barriers are now used for better ventilation.
15. Traditional post-and-beam construction: Traditional heavy timber post-and-beam construction has been replaced by lighter and more versatile engineered wood products.
These examples represent just a selection of the many obsolete home building practices that have been abandoned in favor of more improved and advanced methods over time. I do believe that the practice of pre-sloped mortar beds are just one more improvement over past practices.
While I agree a lot of modern practices are improvements ( asbestos NOT one of them, it was health reasons and not for practical reasons, as asbestos MADE things/products better ), your point you tried to make actually makes my point. From turn of last century drain systems for showers transitioned to "better" by introducing weep holes in drains which were used for 4-5 decades at least. whereas the IMPROVED shower system negates the weep hole system alltogether by implementing a sealed system, as I've done from at least 5 years ago with a liquid topical membrane & silicone at drain neck.....the so called divot system others adopted, or now with a product ( FLOEFEX DRAIN ) and sheet membrane. All 3 in my opinion work dependent on who installs, and all 3 do away with a weep hole mentality which is now antiquated anyway, which is YOUR point, out with old & in with new/improved.
That being said you only have to answer to you, I must answer to a customer base should I fail, and I've had no failures in 24 years.
@@StarrTile No, I'm accountable to a higher power: My wife, my children and my guests that may use this shower.
Your opinions are just that, opinions based on anecdotal empirical evidence you've gathered leading to your own conclusions, nothing more. You are an installer that chooses not to follow what's become an industry standard practice. In that respect you SHOULD be responsible to your customers.
Industry "best" practice is this:
"In a stall shower, the plumbing code requires the floor to be sloped one quarter (1/4) of an inch per foot in order to carry the water effectively to the drain. This slope, according to the TCNA Handbook is called “sloped fill” or commonly known as the pre-slope. This sloped material is installed under the pan liner (waterproofing membrane)."
The industry best practice (TCNA) for installing a shower bed with a sand/mortar mix is to use a pre-slope. This practice has been widely adopted and recommended by industry experts, tile manufacturers, and building codes for several reasons:
1. **Water Management:** A pre-slope ensures proper water drainage towards the shower drain, minimizing the risk of water pooling and potential leaks. This is especially important in showers where water exposure is frequent.
2. **Waterproofing Enhancement:** While modern waterproofing materials are effective, adding a pre-slope provides an additional layer of protection against water damage. It helps prevent any water that may penetrate through the tile and grout from reaching vulnerable areas, such as the shower pan or the subfloor.
3. **Long-Term Durability:** A properly installed pre-slope can contribute to the long-term durability and performance of the shower. It helps maintain the integrity of the shower system and reduces the likelihood of water-related issues, such as mold growth and deterioration.
4. **Compliance with Building Codes:** In many regions, building codes require the use of a pre-slope in shower installations to meet specific performance standards and prevent water damage.
That being said, it's essential to keep in mind that industry practices and recommendations may evolve over time.
I too am guilty of selectively deviating from industry practices sometimes as with the trend in faucets whereby they have limiting devices to prevent scalding. I'm 72 years old and in my lifetime never have had to rely on such devices to 'protect me from myself'.... I remove them from the faucets when installing them.
It is actually mandated by Florida Building Code to pre-pitch your shower pan before installing a pan liner now...at least in my County
yes I work in alachua county fl, and pre slope is required
The man I apprenticed to explained to tee the same that you explained. His 40yrs experience and my 20yrs never used or had issues with a preslope.
I know this vid is 2 years old, but it reminded me of an experiment back in middle school. If you take a stalk of celery and put it in food-colored water, the stalk will suck up the liquid far above the lowest point of the container. It’s an easier visualization of capillary action. So no, water doesn’t always go to the lowest place.
Great Video and experimental proof, capillary action works!!! If that slab had been allowed to sit a month, like in an unrented apt, then it would have been bone dry whether the pan was level or not, capillary action trumps gravity!!!
Good Job! And yes, a shower pan that is old will have a lot of smelly stuff in it due to all the tiny dead skin cells and stuff, unless it's Red Gard'd!!!
Preslopes make me feel good, plus they help me in defending myself when I get sued.
@Matt The Builder. Exactly, that's the point I was trying to make.
If your shower doesn't fail, will you still get sued?
@@johnnybear111 if your shower isnt pre sloped, is it gonna fail?
We waterproof entire shower now, making the pre slope a moot issue
I have been a flooring professional for 30 years. You my friend are a critical thinker and what you are explaining makes absolute sense. The question now is " how saturated do you want the mortar bed to be"? You have my attention.
Wet is wet...capillary action insures all pans ( water in water out system ) will always remain wet in void of air to dry out.
Going forward we all waterproof the the surface now, be it liquid topical membrane or a fleeced/clothe...
Keeps any moisture out so the pan is only for a slope at surface.
@@StarrTile Im pretty convinced that keeping moisture out of the mortar bed is the answer. water needs to go directly to the drain without absorbing into surfaces period. Water needs to escape before it can gather or absorb.
@@gwynja3191 Glad someone mentioned this. I was going to suggest that Isaac, mentioned in the video, uses a membrane over the drypacked pan (please correct me if I am wrong). Wouldn't this be the best practice.? This video is very eye opening and appreciated!
@JoeySchalger @G Wyneja3
someone posted this in the comments, since you missed the entire point of his demonstration.
"Everyone agrees that preslope helps. what he is trying to show you is that water will pull itself out of the drypack and into the drain without preslope. Preslope is only a requiment when you are on a concrete basement floor and the floor slopes away from the drain. In this scenario in his video, the base is perfectly flat and then the liner goes up the sides so it's like a preslope of 0 which in theory will drain. But when you have the slope of the base going away from the drain now you are relying more and more on the wicking effect to pull the water up the slope and over the hump. there comes a point then the water isn't strong enough to wick itself dry because your base is sloped so bad. SO if your base is flat this video proves it drains"
Everyone just convert to topical membranes and move on. I started off doing preslopes then went topical. Won't go back.
S9...I am installing or cutting into a cement floor to have the shower tile sloped into a floor drain. Can I just place a strip of pan liner around the edges up on my 2x6 backers and extend down into the pan not putting the pan liner all the way down to the drain? Of course I will be putting thin set to smooth out the cement to put the tile on. Thanks for any input
Hey Bob have you ever used custom float instead of sand top mix?
I'm with you Bob !!!
how do you think the weep holes will drain water if water is stuck in a corner cause you don't have pre slope
My thoughts too. Even though the bucket fills up that doesn't mean there's not water in the low spots. If the pan stays saturated it will not wick up low spot water. But I guess if you're using the shower every day, the pan will stay saturated anyway causing it to fail.? I'm concerned with water remaining in low spots and creating mold/mildew.
Doesn't water ALWAYS find the lowest place it can get to? Preslope helps a lot. 25 years everyone. I know how it works.
What Bob is saying here (not that I agree) is that since moisture is drawn from wet to dry areas is that the capillary action will soak up any standing water on the liner like a sponge, as the mortar bed drains into the weeps. As it drains from the mortar into the weeps it lowers the moisture level around the drain which draws moisture from the outlying areas up through the mortar bed (or sponge)
Just a word out there for all the Tiny House [on wheels] DIY builders -Pre slope the shower, because you KNOW the trailer supports are going to sink 😉
Great video! I like how all your videos are thinking videos. Details matter for sure & the solid pebbles blocking weep holes makes sense.
what are the dimensions of your demonstration rig? Do you think the results would be the same if it were say twice as big or three times as big? Main reason I ask is because at around 13:20 you add a quarter inch shim to one side, unless your rig is only a foot wide ( which it appears to be larger than that) then that is less than a 1/4 inch per foot, if its a 2 foot span then you are only at 1/8 inch per foot so that's the first issue I see. Second if it is 2 ft by 2ft a 30" circle would not fit inside and then it's not even a legal shower size so the whole demonstration is pretty much a novelty at that point because it doesn't accurately depict a real world situation. It would be interesting to actually do a side by side comparison like you mentioned on Issacs video. One with pre slope and lets say one with a backwards pre slope or one that is sloped to one side since we rarely find a flat and level floor in a real world situation.
Lol nice catch about the shim
When I did my first shower I did a pre slop mainly because I did not counter sink my drain like you do. So since I had to bring the floor up to the drain I did it. Like you say it couldn't hurt. But I also believe it is not necessary . Especially if the liner is installed correctly. Keep up the good work.
I do agree your point that a lot of ppl just listen and follow, they don’t even think or understand what and why they do in any particular way. Even a lot of professional guys don’t even dive to think. Don’t just listen, be skeptical and alway try to challenge with humble, this is how thing get developed. Great video!
Cool demo
I’ve built upwards of 150 tile showers with no preslope no call backs
Those who do a preslope I’m not saying there doing it wrong either but your demo shows no preslope is not wrong either thanks bob
That doesn't prove you did 150 showers the right way...
Amos R let me guess you are a presloper
Well good for you
@@danabennett7795 I don't do pvc liners surface membranes schluter or laticrete products.
Then if you don't use PVC products then how do you know that no preslpoe is wrong ?
@@danabennett7795 I did pvc the first 10 years of doing tile..and guess what did them all wrong no presolpes just a bunch of water holders...I can assure you presloping works.. around here the code was changed because there was so many problems with pans holding water....I'd call oatey tec support talk to those guys..look into ntca approved methods . building codes they all will tell you a presolpe is needed...and of course you can always say well star tile says it's not needed and did a test so I'm going with that..and that's your choice but and the end of the day if you're a true professional you'll do things to code and manufacturers recommendations..any thing out side of that there is nothing to back you up if you get sued .
Slope or no slope. That is the question. I've watched both videos. Both to me look fine. But if I was to err on the side of caution, I would put in a preslope. Just for peace of mind.
Awesome. I wanna do a tile shower was just going to get an acrylic pan because a pre slope was too intimidating. Thanks for the info brudda
what is a mold sandwich/ I dont get using the redgard on the base
Wonderful work bro!
Question what would happen if you read guard the top of the mortar bed
I do that..so yeah it makes the experiment a moot issue. But you need to be sure the Redgard is worked in at the drain good so no water gets in pan, a bead of silicone before waterproof too
Bob, good demo, much appreciated. One question, could you waterproof the top of the mud to prevent water seepage through the mud base?
I have been doing that for the last three or four years now, so yes, the shower should be functional with no tile on it
Thank you Bob, I’m converting my tub to shower on concrete slab, and will apply a few coats of waterproofing on the mud base before laying the tiles.
Keep these videos coming.
The thing I see, is the pre-slope (just like the no slope) requires 100% saturation to work. Both you and Issac showed that. But if just one cup of water was put in at random all around, how much would leak back out? Putting on a layer of tile with the correct grout (by a professional, not an amateur like me) means almost no water will get in. Yes grout is porous, but done right it would only be "dampness" that SLOWLY gets through. All the shower water will run over the surface and down the drain. Like you said in your 2014 video, for the water to be able to actually run down a slope while covered in mortar/dry-pack it would have to be absolutely saturated and if THAT much water is under the tiles, then something is badly wrong and the entire shower floor will need to be torn up because grout and thinset will start crumbling.
i think thats the point hes making the shower has to be replaced eitherway if your having this problem so why do the preslope
if your applying a mud shower pan to a concrete slab floor do you still need a Oatley liner? or could you just put three coats of red guard over the top of the mud pan then tile over it?
I would say that you don't need a pan liner. As long as you use the 3 coats of redgard, which in itself is a pan liner.
Awesome video. Never did use peples around the drain. If water can get through the mortar to the painliner, I always thought it could get through the mortar in the weep holes. Prepitches are required by code here in Florida.
Hi. I am planning to build a walk-in shower on the concrete floor. Would it be ok if I build a slope right on the concrete floor (no pre-slope) and not using the pan liner at all? I plan to use red guard on the slope before laying the tiles. Do you recommend this method? Thanks.
czcams.com/video/u5BvIdx8Y60/video.html
Does the mortar adhere to the rubber underlayment like glue after it dries? Or after the mortar dries and shrinks a little, would it be possible for some space or gaps to occur which then the pre slope would always be aiming that residual water back into the drain?
Although I would like to answer your question we are all doing a sealed system which now makes a pre Slope a non issue and antiquated
I have built many pre slopes using 22/32 plywood cut to fit over the shower sub floor. A 3/4 riser at the outside and 2” drywall screws around the hole cut to clear the drain will provide an almost perfect slope to the drain. Good demo, thanks man!
I like your way of affecting a pre slope without mortar, sounds logical to me👍
I have seen guys do it with ¼ cement board, blocked up at the outer edge, and screwed into the floor at the center, with thinset to the up the slope under it.. the screwed once that's set.
I'm not brave enough to try it, but it's clever, if nothing else
Hi there. Thanks for your videos. I have a question regarding the demo of an existing shower pan on a plywood floor and whether you can reuse the same drain assembly (upper and lower flanges plus the drain barrel) after demo? I am assuming that the subfloor will be sound. Do you generally replace every drain when you demo an old shower pan? What is common to expect?
I would never entertain using the same drain assembly that you are taking out, Only Exception is if it was just installed last week or last month where I know it's pristine, I always replace the whole drain assembly including the P-trap, but that's just me
@@StarrTile Thanks for the continued insight!!!
wow Ive always done a pre-slope but I think Im convinced, I will definitely try to avoid doing them. Water always finds a way I guess. still its the Gravity pulling water down creating a drier area near weep holes and that drives the capillary action .
You answered your own question. Absence of any additional water...the bed will dry towards the drain/weeping system...via capillary action.
to my understanding, you said the soapy shower water deteriorates the sand-mortar mix. It deteriorates the cement components and leaves the sand behind. So anytime water gets into the mortar mix is bad? Is this correct? or is it ok for the mortar mix to get saturated? I realize that you use thin set around drain and you mention it helps the redguard waterproofing to adhere better. that was said in another video of yours. then you coat with redguard. This is to ensure that water never actually enters the mortar bed but it is there as a backup? This is my understanding of the video, am i understanding correctly? This is very helpful to me.
The backup is the pan liner. If installed correctly, it should also stop water getting into the mud bed.
If a sand mix is going to deteriorate anyway...Is there a better material to use for the pan?
So going forward, nowadays most tile guys are waterproofing the mortar pan surface so it is not an issue anymore
I posted this over at Isaac Ostrum video comments and curious what your thoughts are?
A Case for Non-pre slope
Just being the devils advocate here. First off I always put a pre-slope in my work due to avoiding any future liability but I don't think it's as important as we make it out to be. We need to keep in mind that the porous deck mud acts like a huge monolithic coarse sponge. Any monolithic material composition with particle sizes below 0.100" or less than 1/8" will have capillary action and will hold a "perched water table" at a certain level. I don't know what that level would be for deck mud(would be a great experiment as well) but it's there even if i't a 1/4". In a gardening container pot with the average potting mix you could have a perched water table as high as 3". An example may help. If you soak a long sponge in a bucket then hold it vertically letting the excess freely drain out and let stand for a while you will notice that the top is quite moist but if you squeeze the bottom then water pours out. That's the perched water table. Even with no pre-slope there is never any "standing water". I have never found much "standing water" in these demos. There may be some free water but it's mostly due to large cracks losing it's monolithic structure and or a large negative slope but not directly due to no pre-slope on a flat floor. Any water higher than the PWT is drained out of the weep holes. Moisture above the PWT is held tightly to the particles by capillary adhesive forces.
I appreciate your insight at explanation.. Perhaps others will benefit by it.
It is interesting to me that you are the fourth person to comment that you do a pre slope in order to avoid liability, I have yet to pull out a saturated smelly shower, or even one that had cracked from the constant water presence that was less than 5 or 10 years old, most have been in excess of 20 years plus that were Builders grade and many of the things were done incorrect. If I ever thought that not having a pre slope would lead to a failure in a year or two then I would definitely be on board to do them, it is just not the case
@@StarrTile 'perched water table' is the correct description.
Great videos
I’m working with a Schluter pre slope offset pan. I’m laying 4x8 tiles for the shower floor which is a lot bigger than the 2x2 they recommend due to how the pan slopes. Without doing relief cuts or risking lippage, could I more or less lay these flat?
4inches by 8inches right ??
Not 4'x8'😂
However you work those out you would need a positive slope to the drain even if that means doing angle cuts symmetrically on the tile
@@StarrTile Fortunately only 4 x 8 inches. Ok. Thank you for the reply, sir.
So how you make 100 percent water prove, not saturate to the pan at all.
Leave the comments open Starr lol. I wanna see others opinions and facts to see different aspects great video as always
Comments will stay open , I just won't debate the issue any further
OK guys. First I'm not a tiler, remodel expert, builder. I am however a stickler for doing things right regardless what anyone wants to do. In my opinion both of you are right. I've watched both of you do your thing and you both seem very competent and skilled. I like watching Bob, no offense Eric. Bob states he is in this video thing to help people like me figure out what to do and what not to do. He takes time in his videos to explain (sometimes twice or more) what he did and why he did it that way. Makes perfect sense to me. He works alone running his own business and I expect being in Atlanta has more work than he wants, perhaps not. Regardless if where you live and work requires a permit and strict adherence to building codes then you do what you have to do. If you are reputable and do good work, back up your work with your reputation then you should never have a situation where the client is "out to get you". Now some might say that those building and zoning people don't know crap. Well, they are the customers best hope of making sure his job gets done according to some else's guidelines and requirements thereby keeping professionals or semi professionals honest. In Georgia, where Bob and I both reside, there are way too many folks out there running around claiming to be something they're not. Which makes finding a pro somewhat difficult because ultimately the customer really doesn't want to pay anymore than a fair price for quality work and materials. Eric, You run your own business with employees, that means you not only have keep track of what you are doing but what they are doing as well. I'm not advocating that your folks are not trustworthy or skilled in what they do, but I do know first hand that "when the cats away, the mice will play". I've learned alot in my sixty nine years on this planet and I am proud to say alot of it was because I pay attention to detail, after all the beauty of any job done right is all in the details, Bob pays alot of attention to details and makes that clear in his videos. I have a small project I am considering right now, I know how to get started, but if things go badly or not I am working with obsolete no longer made tile. So I may call you Bob. Good luck to you both, I just had to chime in. It's my opinion and I'm sticking to it.
waterproofing your mud pan, does it effect the adhesion of the thinset at all? and with no pre-slope, what stops the pan liner from shifting? just the weight of the mud bed?
If it affected that he's in process I wouldn't be doing it so the answer would be no, and yes the weight of the mud bed stops movement, typically 150 lb to 200 lb plus of material
@@StarrTile your videos are great, I love the fact that your willing to help and answer questions- I dont see the need for a mud pan under the liner myself, and greenboard is great, logically makes total sense to use for walls, but people freak out when they see or hear it
Don't know if I thinking cornetly... If I do preslope and than read guard on the top than slop... Than if Wather penetrate slope.. Stop on read guard and goes down cuz preslope... Right? His with out preslope Wather gonna stay somwhere in lower spot... Please explain
Thx
I waterproof the entire surface of the shower so no water will ever see the mortar mix, that's why I don't do a pre slope because it's irrelevant
Yes but Wather stay i nie low spot with out preslope right? And with the time... Gonna be bad smell there and moulding..
Thanks for the experiment. Since you saturated the pan before the final test, all of the water came out since by definition, a 'saturated' pan cannot hold any more water. What we don't know is how much water did it take to saturate a flat pan vs a pre-sloped pan. And as Isaac says, is there a puddle in a corner that might have held less water if there was a pre-slope. And maybe a pre-sloped pan would drain in less than the 12 min it took for yours to drain. Just continuing the discussion. By the way, there is gravity all through the pan and the mud; it's just that capillary action can overcome the gravity for a portion of the water.
Came here to say this
@@user-xt1vs2oz3b Yes I agree. If you had a low spot in the pre-slope ( or no slope ) it could have been 100% saturated in those areas. I think it's over saturation that breaks down the deck mud. The deck mud turning to sand is from it being over saturated for an extended period from clogged weep holes. So those low spots with no pre-slope will turn to sand before long, it's not from shampoo.
Issac is da man!!! Love his tests. Pre slopes DO work. Have torn out hundred year old showers that prove it.
Isaac's video was a scam..he used troba mat, that is used in landscaping not in showers, if you try to use that mat in a shower you would have a complete utter failure
@@StarrTile i am not sure i have seen the video you referenced. But i have seen lots of his videos and think he does good work. His tests definitely do inspire one to ask questions which is always a good thing. I am by no means an authority as far as tile goes, but do work with tile everyday and recognize he does quality work. First of your vids i had watched. And while i wont tell you you are wrong, i have torn out quite a few that were 50 plus yrs old and bone dry.
The mock-up of the shower pan that he did, use a mat that is not used in showers to get a foregone conclusion results from that video, he knew water would come out at a quicker Pace than my video if you use that Mat, that was cheating and he knew it.
I'm not taking away from his skill-set but having at least five or six videos of failures tells me something about his build methods.. that he goes back to fix them and then makes excuses as to why they failed oh, it's never his fault... I personally would not hire any professional knowing that they have a failure rate like that.
Even mistakes that I have made on a job are rectified while I'm there, I've never gone back on a job as he has years later. He provides some good information but he is also too much of a book Soldier that can't think outside of the box, another issue that I have with him but wherever you can get your information the more the merrier 👌👍
@@StarrTile i do feel ya there. Havent had too many/ any where i have had to return. But hate to say never and jinx it. I must admit, i dont do as many showers as i used to as i do more commercial these days. But you are correct in that i do usually try to fix mistakes before i leave for good lol. Anyhow, wasnt throwing shade. Just saying i had seen his stuff and it looks like he does respectable work.
Spot. Thank you . And once water saturates the mud bed, it’s never really gonna dry out, especially if it gets used all the time
Convinced me to go with some type of one piece shower floor - there’s Darcy’s Law, but Jurin’s Law ultimately wins via time and invisible defects.
Pre-slop or not pre-slop? I am remodeling my own bathroom and this question got me puzzled all over. Could not get to point why should I do this sandwich, so went to no pre-slop. But very pleased to find discussion here on this topic, that helped me finally to get to the point why many care for pre-slop. 1: Let water to get out from low spots in top layer of mortar. 2. To avoid liability.
Thanks so much for this clarification! But I am not about to redo none slop pan that I already did. Just curious, I painted the the top layer with waterproofed paint, what difference it might make? Also I painted under the liner all the sides of the shower to prevent from tiny ants coming because I saw them under old pan when removing it. Those beasts are the nuisance in FL and they get to any place in the house where they have enough moisture. The shower is one one of them and I wonder that no one is offering the way to fight those creatures.
My thing is , everyone uses silicone to seal your liner to the drain itself. How do you guys think the water will exist under the liner if its sealed to the drain?
Thank you for all you work you putting into you videos.
As to the test: You could have done a simpler test. Do not install mortar and pre slope at all. Just have that PVC liner. Once you pour water first time (what you did with pre saturation) you will see puddles of water on PVC. After that no matter how much water you add you will have same puddles and the same amount of water going in and out at the end. If you will have only pre slope you will not have puddles . So pre slope will not allow pockets of staying water in the mortar. And for capillary action magic in the sand: If you are on the sandy beach next to the water and start digging a hole in the dry sand you will get puddle of water eventually - close to the water level of the lake/ocean/river. Puddles (pockets of water) may stay in the sand even if the surface is dry.
This is on point. So if there was standing water or water that got in under the tile through the redguard, there would be puddles without a pre-slope and no way for water to evaporate out if the top was sealed. This will cause mold and rot. So always pre-slope and never add two layers of waterproofing (liner and redguard). That is just a recipe for disaster as the water will be trapped. You always want to have only 1 layer of waterproofing and let it dry out to one side or the other.
@jc5543 your method you describe was done for last 40 years or longer, we aren't doing that anymore...welcome to 21st century and sealed systems, mine is redgard, Aqua defense, hydroban, or some other liquid topical membrane, other people's method would be sheet membrane attached to the surface of the mortar, still sealed system. My Redgard won't fail 100% so your sky is falling hypothetical holds...hmmm...no water 🙃
I had a guy do a mud pan and tile for me about 3 years ago. Recently I re-grout the perimeter of the floor and I accidentally broke a corner of the wall tile when I removed to fix it I could tell there was lots of moisture in the are behind that corner. So knowing the bed is going to get wet how do I know if it needs to be torn out and redone or if it’s ok and not worry about it. It’s a nice looking shower and I would hate to redo the whole shower. Thank you!
I don't know why but every tile guy proposes to do 100-year shower, but the reality is everything has a shelf life in your house and eventually the shower needs to be redone, probably 25-30 years down the road.
Then again there is not a monolithic way to build a shower so there's always operator malfunction, that you had an issue 3 years after the fact just shows his lack of knowledge, the surface should have been waterproofed.
But my Mantra is if it's not broke then don't fix it
@@StarrTileThank you for the response and advice! I really appreciate it.
If a serious amount of water is getting to your mortar won’t it just absorb it and slowly weep it out regardless of whether it is pre-sloped or not? Unless a small amount of saturation in the bottom of it somehow damages the drypack it seems the pre-slope is more of a precaution against a poorly or improperly installed pan-liner making it pointless if it was installed correctly in the first place. Just my two cents.
The only real advantage to having a pre slope is if your subfloor is off-kilter and you don't Rectify that before the pan material, then a pre slope would benefit you
Epoxy grout with a non porous material such as porcelain
I have had second thoughts about this matter. If a small leak was to happen in the bottom of the pan were the first water collected then that water would RUN OUT the leak and then that water would be topped up by the next shower, repeatably. With a preslope all water would run out and only a minor amount of water would be available to leak through. So if that is true then the matter to be faced is if anything goes wrong with the pan liner install then the potential damage below is minimised. With a flood test the water pressure above would push down on the pan liner minimising leak flow. the empty tile bed would not exert the same sealing pressure. So both tests work but the long term out come from the failure of a less skilled installer may be minimised by the preslope. I am about to do a second bathroom, the first i did years ago without any water proofing on a ground slab with a slope to the outside. I 'lucked out', no damage inside. I just followed the old trady's advise at the time. This time upstairs no mistakes.
I thought the pre-slope was made for underneath the liner so the water would run down the liner into the drain if there is a leak ... am I wrong? Would a slope not help in this case?
Jeremy Aitken
The other gentleman that he mentioned did the pre-slope experiment.
This video was his response doing a non-pre-slope experiment.
“Get it”?.
Exactly what I was thinking. If you pre-slope before the liner the correct way, you don’t get any wicking. It will just be a sloped liner instead of a flat or level liner.
Thanks for the video Bob! I agree with your methods. I wish you were able to show the plywood underneath after the test. Just curious if it was damp.
Uncle Bud
He put the rubber shower pan before he put the mortar bed.
Why or how would the plywood underneath get damp?.
It's called condensation. It does get damp but since the area below is dryer the subfloor moisture can wick to the dryer area. But this is definitely not good for OSB or plywood over time.
I can understand the wicking action that occurs but are you thinking that the floor below the liner doesn't need to be at least level in the entire shower floor space because the cap action will absorb the water and then gravity at the drain weep holes give the water the pathway to get out? If so why worry about the drain base being flush with sub floor?
Yes in an ideal world you would have your floor flat and level, but then again your bottom flange where your weep holes are and troughs that are cut out of the drain are only a quarter inch high so the most water you would ever have to pool would be a quarter inch at best and that's not going to stay stagnant because it will wick up through the rest of the mortar which arguably is plus 200 pounds, having said all that we are not doing the in and out system anymore we are waterproofing the entire surface so the whole wicking action and pre slope and all of that is a moot issue
This is awesome! Thank God I don't have to do a preslope...
I do not use pebbles and use the plastic disk too. So I agree on the point. Although the issue with no preslope is to help water from pooling in the corners of the pan or the low spots. This video shows those low spots. Now the issue is mildew growth. I have seen it on ALL non-presloped pans. All the corners will have mildew growth from under the tile and can never be removed. All of the presloped pans do not have this issue.
Sure not using a preslope is easy, drains 90% of the water, but mildew growth in the grout lines is a major issue with this.
This video is a prefect example of water pooling in the pan. All the water would have drained if there was a preslope going all the way to the drain. The mistake is Starr just props up the edge of the pan not the whole pan.
Would an alternative pan method be sloped mortar base(no membrane) with a recessed non weep hole drain, coated with two or more coats of Red Guard with the coating continuing up the walls. Would this be the same as Custom Products preformed foam shower bases with Red Guard (but much more inexpensive)? Would the sealed mortar base trap moisture between the tile and the base, and create smelly mold and mildew? For a shower used daily, is mold and mildew an issue regardless of the pan system used? I wonder if a daily used shower pan ever dries out during its lifetime? Finally, does all the controversy over shower floors make preformed acrylic and cast iron pans the ideal shower floor?
Great video...thanks for taking time to demonstrate capillary action of water!
I am **totally NOT** sold on the premise that no pre slope in needed. Goes against everything I was ever taught by numerous installers/contractors. Gravity is what governs where water travels. Period. Yes capillary action exists but gravity still directs it. Drive or hike up any river or creek bed and watch nature work. Then paddle down it in a kayak if you have the skills. I agree with much of Starr Tile's logic and his demonstration, and all... But will always include a pre slope element to avoid allowing any possibility of water finding a spot to pool up and hang out. These days with paint on waterproof membranes I fully coat the top surface of my shower pans (Hydroban), usually 3 coats to be sure to get the required thickness. Also I coat the subfloor and the pre slope. I end up with a layer cake which I believe strengthens the entire pan and keeps water from the mortar bed. So after it penetrates grout/thinset layers it hits membrane and is inclined to follow slope to drain. I agree it percolates through daypack just fine through weep holes and other egress points of drain assembly. But I see no reason to exclude slope from the equation based on this video.
Can I ask, the major thing I see different between you and other shower guys is you waterproof UNDER the mortar bed. Many others do the bed right on the slab or plywood subfloor, and then they waterproof overtop with membrane or whatnot and many of them NOW (after I presume watching you) they almost all apply a waterproofing like redguard or it's equivalents ontop of that. If the redguard or whatever is the end all why do the waterproofing under the bed? I've even seen you use membrane instead of a liner on tricky showers before your mortar bed. I'd like to see that test, do you need to waterproof under your mortar bed. I suppose in the end if all else fails it's one final redundancy but you tend to shy away from that besides this.
Suppose the subfloor isn’t level, it’s 1/4” lower at the curb than in the center at the drain. Would you not worry about water collecting at the curb? Or would you make sure do level the subfloor at the start before you do anything else?
Absolutely, that is part of your prep... you have to mitigate any issue when it comes to any project.
StarrTile Okay, makes sense, especially after the results of your experiment. Another question: Oatley says (in their instructions that come with the liner if you buy the pre-cut roll) drill a 4-1/2” hole for the drain and set the drain on the four legs of the bolt mounts on the sub-floor, leaving about 1/2” from subfloor to top of drain top. This gap is filled in with the pre-slope. So this method would provide more support for the drain if someone heavy stepped down on the center of the drain. I don’t know what Sioux Chief says about installing their drains. Also if different methods should be applied to pvc vs abs?
PVC and ABS are basically the same. There's no issue with "weight on drain" if you use the bolt recess or not, it doesn't work that way. The support comes from many sources including strapping the p-trap to begin with. Oatey's video shows many things done wrong, as far as building a shower...do whichever way makes sense to you.
@@CreationVibration You are misinterpreting the Oatey instructions for correctly installing their drain. To start with you are correct, they say to drill a 4 1/2 inch hole to set the drain on.......... Guess what? The diameter of the four legs or bolt mounts is 4 1/2 inches. There is no way that will sit on the bolt flange. The cut away diagram from Oatey shows the drain sit flush on the flat underside of the drain. Secondly, I called Oatey for verification and they told me, yes you arereadin the instructions correct..... the drain should sit flat on the flange underside.................... NOT on the 4 Bolt Housings leaving the drain leaving it to sit up about 1/2' off the subfloor. Wrong!!!
Interesting video. But wouldn’t having no slope at all cause some water to pool on the shower floor without any way of being evacuated other than through evaporation?
Wicking action would ensure that your pan would be wet all the time, the fact that there is no gravity because you're dealing with a mortar bed that gets saturated would not allow water necessarily to pull anywhere, all that being said it's irrelevant now because we waterproof the surface and thereby the mortar never gets wet
@@StarrTile thanks for the reply. But I see from your other videos you slope the tiles towards the drain (your golf ball demonstration).
Love your videos, so thanks for sharing your knowledge! Can you tell me if my thinking is right with this approach:
Using a Flo FX type drain without weep holes makes the pre slope totally irrelevant, , right? My approach is: 1) tar paper/plastic sheeting right over the plywood substrate; 2) staple metal lath; 3) build mortar shower pan with the right pitch with Flo FX installed; 4) install waterproof membrane like Kerdi or liquid waterproof barrier like Red Guard, Hydro Ban, etc. over the mortar pan; 5) install floor tile.
No need for the 40mil plastic liner in this case since the waterproofing is happening on the top of the pan, right?
Yes suppose your way would work... there are many many ways to do the right thing as long as it doesn't leak at the end, I don't necessarily agree with doing it for a customer because I don't want to toss people failure.
Having said that I waterproof the surface of my pan so it also makes the pre slope obsolete... and I don't need the flow drain for that
awesome video.... so I saw a video of you applying Red Guard... is this where I would apply it ? onto the mortar ?and then after 3 layers.... next is thinset for tiles ?
Yes
@@StarrTile would also like to ask you about the type of grout to use on floor tile in the shower floor. should we be using epoxy grout or something else ? TIA
I use Prism by default on every job I do the last few years
This was a awesome. This shows dont reguard the shower floor it stop water going into the weep holes
If water gets into your mortar bed which is mortar then how is it that it cannot get into your clogged weep holes that are clogged with mortar, irrational 😂
May Take 12 minutes without slope maybe with slope take 6 minutes byw u are a great tile master I like see a nice work done bcz i know isn't easy task to complete without years and years on real work field I know what's I talking about bcz I'm a plumber after 25 years I still learning from other trademan 👍
What is the mixture of that mortar, sand and cement? What’s the ratio? Thanks!
Yes sand and cement...usually 5-1 but some prefer a richer mix of 4-1
So those 60 Lb with the green strip,do they have Sand in It??I m confused 🤦♂️🤦♂️.Do you buy a separate bag of Sand and mix together?Big fan of u here.Thank you.
Sand mix..aka mortar....4-1 sand/cement.
The yellow bag with a green stripe tries a little slower so you can manipulate it the next day a little bit, the yellow bag with red stripe dries quicker and you cannot manipulate
So how does waterproof membrane like Redgard affect this test.
czcams.com/video/qdpYnUU_owQ/video.htmlsi=qFVo5UHgYZLyugLP
Solid Bob. Thanks.@@StarrTile
I still believe the preslope will allow more water to find its way out , however i am going to waterproof my shower beds to reduce the amount of water that makes it into the shower base, and hopefully reduce mold build up under the floor tile
Hi will I need a pre slope if my drain isn’t in the middle?
If you intend on waterproofing the entire pan prior to tile you would not need a pre slope regardless of where your drain is
Is pre-slope now code everywhere? My plumber in Florida said he had to pre-slope my shower because of code requirements.
A pre-slope is not a code everywhere, depends on your city, your county, or your state, in the state of Georgia I have never ever encountered a pre-slope.
It is also outdated since we are doing the sealed system and not a water in water out system any longer but codes still linger for years
@@StarrTile Good info. Thanks for the reply.
I learned to mortar the shower with slope without the clamping collar on . Then install a shower pan. Then idk what the tile guy does after that. Which makes sense, like a water slide to the drain.
Do it right. If you don't want a stinky shower a few months down the road, do the pre-slope!
Everyone waterproofs their shower nowadays, including the pan surface....so no water gets into pan, so preslope for what reason exactly ??? 😂
Gotta think about things rationally
I trust your methid. When I build my shower, I will make sure it's done exactly the way you build it, no substitutions, period!
If your floor is perfectly flat you do not need a preslope. This video is like a preslope setting of 0. A perfectly flat base makes it very easy for the water to wick it's way to the drain. Also, since your liner is a few mm thick, when it meets the walls it slopes upwards (there is a curve at the 90 degree) so technically there no negative slope or opposing slope in the pan. it's basically a bucket on a flat floor. If you install the liner nice and tight and your floor is flat there is no reason why it shouldn't drain. You need to preslope when your base is not flat, like the concrete in your basement is built poorly, or when the carpenters build the floor poorly. Or even if there is a very small slope in the overall floor of the washroom. if some of your shower base slopes away from your drain or if the entire floor drains to one side, then you are relying on the wicking power to pull the water up the opposing slope and then into the drain. There will be a point where the wicking power is not able to pull the water up the opposing slope. the wick power is directly related to the size of the pour spaces. the smaller the pores the stronger the water can pull. Wicking is due to the water molecule being di polar. when the negatively charged oxygen in the water molecules come into contact with other negatively charged oxygen elements in the other water molecules they push away from each other. Same goes for the 2 hydrogen elements because ++ push away from each other and same goes for --. when they hit other H's in other molecules they push away from each other. You don't see anything happening at a depth but on the surface of water you can see the effect of the collisions because they are not balanced by other molecules. So the top layer of water doesn't have water on top of it to balance out the o's and the H's pushing off each other so it makes skin like behavior. insects walk on water because of this. A miniscus forms at the edge of your glass because of this. Unbalanced water molecule collisions are pushing the water up the the side of your glass. This happens at every interface between water and air. there's an unbalanced effect.
When you dip a napkin in a glass of water you will see the water rise up the napkin because of the energy that the collisions are creating at the air/water interface. The smaller the pores the higher it will rise because the energy has to carry less weight. larger pore spaces means a larger amount of water needed to fill the pore which is heavier. So the size of the poor spaces in the dry pack can only pull water up a certain amount. If your base is ever poorly sloped then there's a chance that the wick can't drain the drypack. This action also works horizontally, if the water falls into the drain then the pore spaces next to the drain have air in them and the pores adjacent to those pores are full of water so it pushes in that direction.
So a flat surface like this experiment, a 0 slope will work. if you are ever uncertain, just preslope it and don't risk it.
great video.
So you measure a 1/4in at the end of a 2ft level and call that correct. You just said there should be 1/4in slope per 1ft length. So should you not have 1/2in at the end of the level.
1/4 per foot, one foot is one side of the pan
Question why not pre slope under the rubber
The long answer is because it hasn't been proven to work which gets into a lot of detail, the short answer is we waterproof our pan surface so preslopes are a moot issue now
I suggest we do comparison experiments for saturated pan with/without pre-slope to see if there is a difference in the amount of new water that replaces old water. First let's use water with certain concentration of ink to saturate both shower pan mud beds, then use clean water to 'wash' the mud beds to see if there is a difference in the color of water coming out of both mud beds...
That's a great idea and an experiment like that would be the only way to truly know if water is cycling.
Having said that it's a moot issue because everyone waterproof their pan surface now so no water gets in to begin with
@@StarrTile
What do people use to waterproof their pan surface? Redgard?
Yes, or Aqua defense or Hydro ban or 8 + 9 or Kerdi
I appreciate the effort as much as anyone else but people should realize neither of these tests actually prove anything. Doing science is hard. One of the most important parts is having peers poke holes in your methodology. Here we have one test essentially testing the vaiability of a funnel. A plastic funnel with mud on top. Of coarse it works and you'll get all your water back. But that's not what your testing. Your testing whether its necessary over a non sloping funnel with mud on top. To that end it tells you nothing.
On the other hand you have the non slope plastic funnel. That was saturated before hand. Look, its not exactly a huge leap to realize that there is no other possible way for this to end then to get every ounce of water back. That is what saturating is. 100% of the space that could be filled by water..... is filled by water. Where else could it go? You could've built big pools under the mud and you'd get the same result. You've already filled the mud and dead spaces with water (the fact that there probably wasnt any low dead spaces is irrelevent. If there was they would've been filled little pools with the same end result.) Neither addresses the actual issues. Im not trying to be a pro skeptic here but the issue is a lot more nuanced and difficult then this.
As much as I loved mythbusters their methodology had the same issues. It wasnt science. It was just science influenced experiments. You could literally spend 4 years majoring in the ways experiments can be conceptually flawed. Researchers still get disgraced to this day by having their methods shown to be subject to basic biases.
I agree with this statement :) in the end there maybe a small influence of slope (gravity) if there are pools (gaps) in the stratum but its likely quite small. Since the influence of slope would be to increase the speed of the capillary action and time is not part of the experiment in a meaningful way... I am not a professional, so feel free to ignore my comments. I am a DIY, with my own bathroom remodel :) My take away is - slope the pan to assure efficient draining, redguard the pan to reduce influx to the pan, choose/maintain low permeating wall board, tile and grout.