Mr. Concord Carpenter. As a widow I've been trying to maintain my home for the past 8 years. My next project is to insulate my cellar sills. Thank you very much for sharing your knowledge. I now know how to do this. It will probably take me a long time to get it done but that's ok. I can do this! Thanks again!
I feel your pain! I’m right there with you! Sometimes I feel like the widow in the movie “What Dreams May Come” stuck in my house with SO much to do now, but WE CAN DO IT!! Just skip the spray foam against/touching any exterior wood membranes though. My husband was a Forensic Structural Engineer and had tons of inspections where there had been a leak of some kind, but the spray foam concealed it so well, it rotted the wood from the inside out. 😳🤦♀️ Maybe stick with using EPS FOAM BOARD cut to fit each rim joist area and then just use can of spray foam to seal around the edges. Have faith!🙏 Be strong! 💪 Good luck & big hugs to you!! 💛
Speaking as a 25-plus-year widow--since I was 43--I could say the same for the reverse, Adrian. While my husband was a brilliant "thinker," he absolutely DESPISED performing vehicle and/or home maintenance duties. As a "stay-at-home" mother-of-four, those responsibilities were almost exclusively mine.
@@martinabsp5327 Absolutely. Skills and the desire/motivation to perform them are genderless. Your children are lucky to have your example whether they are boys or girls.
This is a great reference! I have been working on my house's addition crawlspace which I have been working on since buying it fixing all the previous owners issues. This is EXACTLY the kind of guidance I was needing for how to properly and effectively insulate the rim joists. Thank you!!!
Glad I saw this before replacing my basement insulation. Liked the comment about leaving gaps around foam board and using small wedges to keep space to get spray foam around the edges.
In most of Canada, previous practice was to just place batt insulation in the joist cavity. Then it was required to have batt insulation with poly over, with the poly just stapled in place. Then the poly needed to be sealed to the joists, usually with acoustical sealant. Then spray foam, just spray foam became best practice. Now the spray foam needs to be also protected from fire with drywall in most municipalities. I regularly perform air leakage tests on new homes (blower door) and we still find that the spray foam leaks air. Not many people realize that air leakage of a home is a far worse issue that lack of or improperly placed insulation. Spray foam alone, is NOT the perfect solution.
Great video! It’s important to note that the installer you show in this video is not wearing the proper respirator for spray foam. Dedicated outdoor air supply should always be used during installation. I have also not done this correctly in the past, but know better now. Keep up the great work!
Actually this is a Froth Pack not a PRO high psi spray system and requires wearing a NIOSH approved organic vapor air purifying respirator with a particulate filter if the exposure to pMDI is unknown or in doubt, especially when spraying where ventilation is limited such as in crawlspaces or where spraying close up. This space was well ventilated with fans. With a PRO system - yes you are correct typical best practices with supplied air
@@ConcordCarpenter I am not involved in installations anymore, but recently have heard that outdoor air supply should be used with pro systems and froth packs. I can't remember the source at the moment. Anyway, I would look into it to make sure.
This is a very helpful video. I started insulating my rim joists a few weeks ago using foam board (r10) and spraying canned foam insulation around the perimeter, while this is time consuming and tedious at times it's coming along. I checked the temperature between a section that was sealed and one that was not, the insulated section was 10 degrees warmer (55 vs 65) while it was in the teens outside. The spray foam insulation is lethal and yes you should wear a mask, once it's dry you don't have to worry about breathing in the fumes. Once everything is sealed I plan on using un-faced Rockwool R-15 to fill in the gaps, based on my research this would work best. I had no idea what to expect when I started this but the fiberglass batts that I pulled out were filthy and covered with bugs, in one joist I found a live hornet, thankfully it was sleepy and slow. In other sections there were live stink bugs and ladybugs (lots of them) There are corner sections that are very tight and I will have no choice but to spray foam into them. I'll be glad when it's done. As far as the brand used in this video and by this Concord Carpenter, maybe that's what he uses, who cares, educate yourself on what would work best for you.
I am thinking of doing the same method in my basement. On the rim joist ends in my house they're cement. The joists are set down into the poured cement foundation. Would love to hear further how your project worked out and if you had pictures to share of the finished process that would be awesome.
Thank you for this. We had our first winter last year in a house we bought, the floor was def cold and it was made in the late 80's. All they did before with the last owner was BAT insulation in the basement for the Sill/rim joists. I was going to do rigid foam boards and then seal them but the benefits of the spray foam I like better. Plus it'll go a lot faster.
You have to make sure you take the time to vacuum and clean out those rim-joints first. So many times they can filled with old insulation, plaster dust, brick dust and just all sorts of debris. I believe you can even take a spray bottle of water to misty area really good, before applying the spray foam.
the foam they are using does not need water it is two part foam that reacts with each other and will harden much better than the cans of spray foam but they are a pain to use if one side comes out more than another it will not work and the hoses and tips get clogged if you stop for too long.
I knew all those off-cuts of 2 inch rigid foam board I've been hanging onto were going to come in handy. Just recently picked up some of those DAP spray foam cans and an applicator too. I've seen my future, and it involves lots of cutting foam board, swearing, and more cutting. Thanks Concord Carpenter, for always pointing the way. Fantastic content as always.
Just came across this video and your basement foam board insulation video while starting this project myself. Very useful and great explanations! Thank you very much!
Spray foam will provide a nice environment for mold as easily as improperly installed batt insulation and vapor barrier. I've done Renos on many new homes only a year or so completed that had moldy, cracked spray foam. All these methods require true craftsmanship and care in order to function as required. I have had well over a decade of experience with every possible technique. In my experience, batt insulation and vapor barrier are superior when installed by somebody who truly values their work.
The problem is getting someone who does take proper care with the work... I end up doing a lot of things myself because I just can't get anyone else. If I can't do it myself, it doesn't get done. 😢
@@maaismak8915 building inspectors also need to be held responsible for consistent blind eye turning. Would be nice to filter out the hacks, so the real tradespeople can get the work done.
2/28/22; insulation...yur video 2day was one of your best/most practical videos. Don't stop your insulation education & presentation to all us YT armchair viewers & weekend handymen. Continue along with more info. New construction: after stud wall framing, Zip green wall exterior sheathing, & brown roof sheathing. Each of these painted osb boards has 2-part poly-iso foam insulation glued to interior side. You can get different thickness of the foam on these boards made for your area of country...extreme cold or hot. But you are not done! Gotta seal (special black tape, rolled/pressed tightly or special black caulk spread, mini troweled into) all those seams of the 4x8 sheets + put same black sealer all around your window & door openings. Their is lots more on this insulation & air infiltration, moisture (&bug) control issue, but you will decide how much you want to present to your viewers. Oh yes, Happy Mardi Gras from (chilly 40°) New Orleans area! Green/brown board, black caulk/tape, poly-iso foam stud spray & blower door tested areas all over US & Canada. Enjoy your channel & testing comparisons for tools...maybe now some insulation comparisons & testing too?🤔👍👍👍🧑🔧🍺
Something about Rob's presentation makes me motivated to do this fix. Oh, nevermind I have slab-on-grade. Great video though. Be sure to wear your respirators ya'll.
I cut and screwed in my R5 tinfoil foam insulation with 2" screws and large washers to fill in all these rim joists areas. I then can spray foamed all around. Good advice to cut 1/2" small. Yes, it takes time. But the comfort, temperature, energy use difference was felt immediately by the whole family when I finished installing an R35 sealed plate of insulation under the whole footprint of my century old house. I can sprayed foamed every seam and junction and then cut it flat when dry before carefully taping the aluminum tape. I also put two 2" layer of tinfoil foam board against the perimeter concrete walls being here in Canada.
I bought a fixed upper cause there are a lot of things I can already do. This winter I had some frozen water pipes (primarily due to the previous owners short cuts). While I'm not yet confident I could do the full spray foam, I will opt for the foam board and seal. Good vid. Thanks
Very good!!! Every ''DIY home owner's'' should watch this video. I have have studied a lot and a lot to do that by myself the right way. I really wanted to have a 100% understanding of the science behind that because i have seen a lot of bad ways to do that on internet. That's a very GREAT video. The way you are talking about what's happening with the materiel is really cool because if the temparature where i live is different than your's, i can made little ajustment the right way. Thank you!!!
Having had this done a little over a year ago upon the recommendation of an air-sealing company, I can say spraying with closed-cell foam has some major drawbacks: It never can be removed if necessary, makes termite inspections impossible from the inside and hides termite damage, makes hunting for leaks impossible, traps water against the wood framing being closed-cell foam if leaks develop which will promote rot. With these observations in my home, I'd caution against it. If anything, I'd suggest using foam to seal cracks and then use bats or foam board. Keywords in the video are quick in and quick out which is exactly what this company I chose did and cut corners which I now regret and will have expensive mitigation in the future.
Exactly! Spray foam insulation is the "new rage" and it is a Gd awful mess. Carcinogenic chemicals and impossible to ever fully remove. Tell me why the installers need to be in full hazmat suits but the homeowner or renter is fine to breathe it in over years? Does it somehow become inert once it hardens? No. No, no it doesn't. Also, find me ONE electrician or plumber that likes this stuff...you are literally hardening all wire and pipes inside this foam. Watch all these videos on YT. It's insane. I can't even fathom why these guys can just do this and not think about the future. There are far better materials for basements that are mold resistant and rodent proof and for walls nd attics above ground. Please stop this spray foam madness.
sorry to be so off topic but does anybody know a tool to log back into an instagram account? I somehow lost my login password. I love any help you can offer me.
@Enrique Charles Thanks so much for your reply. I found the site thru google and im in the hacking process now. Seems to take a while so I will get back to you later with my results.
Many thanks for your insight. Had a generator installed and those electricians really suck at putting the insulation back and now 25% of the house is ice cold because the bans joist where they installed a couple pipes are icy cold all winter and the floor is icy cold. Was trying to fix it with all kinds of ideas but flash and batt will work for me. I have the batt. Just have too much outside air penetrating the cavity.
I just insulated the rim joist on my house in southwest Ohio. I used caulk to seal the gaps the R-15 mineral wool. The reason I did not use foam board or spray foam is that the house may need a termite inspection in the future and the mineral wool will be easier to take out and put back.
The problem is that the mineral wool, like fiberglass is air permeable. Therefore, you risk moist air passing through it and condensing on the cold rim joist.
@@percyfaith11 I'll keep an eye out for that. I had to remove one piece after the first winter to fix a pipe. I saw no problems. With closed cell foam or rigid foam boards I would be worried about moisture passing through the wood from the outside then condensing on the inside and having no way to evaporate. Caulking the seams all around is very awkward and difficult but that step alone probably gives a huge benefit since it stops the air transfer.
@@chuckhall5347 Chuck, in the winter the inside of that wood is warmer than the outside, so there won't be any moisture condensing on the inside of the wood that comes from the outside. Besides, in winter, the outside air is extremely dry, if you live in a northern climate. It's only inside humidity, generated by breathing, cooking, etc, that can get to the cool inside surface of the rim joist and condense. Unless the rim joist is continually soaked in water, humidity won't go through solid wood just from being water vapor in the air.
Just gotta say thanks now I have better understanding of this part. And need to find best way for me to do the job and fastest n cleanest. Think I’ll do a mix of 2/3 of these. Tight area 2inch spray and then foam board with spray foam in others.
The video should say, you MUST wear the right respirator when installing spray foam. You can have serious lasting health problems caused by a single application with improper protection.
If the rigid insulation is also the vapour barrier, shouldn’t the fibreglass insulation be installed first? Why would you treat this area differently than the rest of the house, that is, vapour barrier on the warm side? Edit: What should be done with the exposed concrete by the sill plate? Foundation 10” thick with a 2x6 sill plate leaves you about 4” of exposed, cold concrete.
I did the 2" rigid foam board with can foam around the edges, and then batt insulation, for a 2700sf house, so not a big basement. All I gotta say is, be prepared to spend a LOT of time in the basement sticking your head between the joists. The spray foam option for rim joist air seal/moisture barrier is worth the extra money.
I did the same on my 1400sq ft basement. I thought it was well worth it. Cheap material cost, and once I got in the groove it went in fast. Probably was at it for 8-10hrs spread out over a few nights. Thermal imaging camera showed it sealed nicely. When compared to spray foam cost, the possible health risks, and the requirement to vacate the house for 24hrs due to fumes, it was a no brainer.
Awesome video, as usual! Here in Canada, Newfoundland to be specific, we always need vapour barrier. I believe due to the climate, vapour barrier is not necessary in some parts of the US. Ours is typically plastic (poly comes in rolls) on the warm side of the insulation/wall system - between the studs and gyprock. It sounded like you were indicating that the rigid insulation or foam placed on the sill (cold) beam would act as the vapour barrier. It could then be added to with rigid, foam or fibre glass insulation. This seems nearly opposite to how we do it. I understand that different climates call for different best practices. Some places put the barrier in different places within the system. Flordia would be very different from here I suspect. The continuity of the vapour barrier throughout the house is also very important here. Love your content! Please keep it coming!
as long as drying potential is on both sides of the foam you should be fine. If you had a foil face insulation on the outside or another vapor barrier inside of the foam then that would cause issues. If worried about the vapor barrier on the foam peel off the plastic film. Personally I would just caulk the seam for air seal and then use rockwool insulation
The vapour barrier needs to be on the warm side of the air space. With batts or loose fill that's just under the finished wall surface, usually drywall, because moist air can move through the insulation. That means the vapour barrier will stay above the temperature where moisture will condense. With closed cell foam, the air can't move through, so you only need to make sure there is no air space where it meets the cold surface. In this case, any condensation will be on the outside of the sheathing and can dry to the outside.
Hey, Rob! Would love if you would do a video on how to find studs in a wall when it's hard to find things that reveal it's position, eg. behind standing wooden panel.
I was wondering if I should use my leftover XPS board to replace that blackened fiberglass bat. Now, I'm 60/40 going to use it, just needing more research about vapor barrier wooden rim joists should that exterior moisture be retained within that wooden rim joist; won't it accelerate rot?
I understand what the experts state. I just can't wrap my head around that they're saying there is MORE moisture getting behind a much colder, unconditioned cellar batt (if sealed properly) compared to a 70/76 degree conditioned space with batt walls? 🤔
Thank you for a video with footage that is nearly identical to my situation. I have openings in the cinder blocks at the top that are extremely drafty in our Wisconsin winters. I'm leaning toward 2-part spray flash and batt method vs the other options. Instead of fiberglass batts, I'd use Rockwool batt insulation after spraying Dap foam. 2" spray foam along with a tight fitting batt of R 15 Rockwool should give me plenty of R value. Rockwool is also an additional fire barrier. Here is my question: Is it advisable to stuff the open cinder block cavity with some rockwool batt then 2-part spray in the rim joist area and over the cinder block filled cavity? I'm concerned that the cavity is just too wide for the foam to fully seal on its own. Thanks again. 😊
I always understood that you vapour barrier on the warm side of insulation, that if it's sealed on cold side moisture will condense between insulation and vapour barrier . We get temp to -45 and can feel cold on floor perimeter , it's insulated with 2" of styrofoam rigid between joists but I'm thinking of spraying over and sealing the ends of the joists . You seem to advocate sealing the rimboard then styrofoam inside
Very helpful info! Recently purchased an older home with unfinished basement/garage that is also home to gas water heater, furnace and most household plumbing. I'd like to provide some insulation, but do not want to cover the cinder block walls as I prefer to keep them visible in the event of future problems. Would insulating only the rim joist with spray foam be beneficial?
the rim joists are much more important than the block walls if the walls are underground, they don't lose as much to ground as the top sill area to outside air you can dump Styrofoam peanuts or vermiculite in top of block wall openings for insulation inside i tried perlite that stuff is awful if you breath it in you need a good respirator. then when you get near top seal the top of block wall with some Spray foam in the openings.
I hate those froth packs with a passion we used them at work, and they would get clogged all the time one side of mix would clog and you would get a mess.
Stopped using fiberglass insulation completely. Use rockwool exclusively, which is way better insulating and fire block. Really do not like using spray foam. it is messy, looks like crud, and not forgiving of mistakes. The other issue, is sprayed right against the wall, it eliminates any air space, and can be a cause of moisture retention, then mold. I typically put up bead board, against the wall, between the studs, which then a vapor barrier, waterproof liner over the bead board, then rockwool, then 5/8" sheetrock. This is labor intensive, but the results, quality is worth the effort.
I understand the flash-n-batt for the rim joists and between joists but what about exposed cinder block wall below it? Should I install foam board and/or treat with drylok?
Hey guys, schoolboy question from me. Doesn’t something like this raise concern? Say you have below you have a timber floor, and between the sub floor and downstairs ceiling plasterboard, between the cavity you already have rock wool insulation, and now you are sealing the gaps around the joist-to-plasterboard… Shouldn’t you leave some gaps for airflow?
If you cover the sill and rim joist with foam, won't the moisture within the concrete walls eventually find its way to the sill plate and then the rim joist, causing them to rot?
Fiberglass baths are also good for rats and mice to nest. I pulled some down and found a bunch of mouse droppings. Im ripping it all out and re doing it!
I would think you'd have to put foam board on the top of the concrete wall between the joists. (In my previous house the top of the basement's concrete block wall didn't have a sill plate either. I was surprised when I first saw it.)
Hey Rob, thanks for taking the time to make your videos. They've been very simple to follow. I have a question about proper insulation in a catilevered bay off of my kitchen doorwall. Very cold floor there in the kitchen during the winter. I can access it from the basement (conditioned space below). wondering which surfaces should get rigid board or spray foam in the cantilevered space. Thanks for any help you can provide. Im in Michigan If that helps better understand the climate. Thanks again.
As a retired insulator who had 23+yrs in the trade, I found that foam board pieces at the perimeter ( as in the non- cantilevered rim area), then another piece of foam board flat on the area FROM perimeter rim to the sill board at the top of the block wall, then sealing all edges of the rigid foam with spray foam( great stuff or gun foam) works the best, and meets code in most cities.
I'm getting ready to encapsulate my crawl space. The foundation cement block is porous. The contractor claims that leaving this space will negate the effect of the encapsulation and he will not guarantee the work if he does not foam over the entire foundation. I have decided to paint a couple coats of masonry waterproofing paint on the top 6-8 inches of the foundation block just below the sill plate and placing the foam starting 4 inches below the sill plate. It should maintain encapsulation and provide an inspection "window" for termite tubes. In theory, if you do not leave the space termites to gain access to the wood from behind the foam. There are a few videos showing the value of keeping this area exposed but they do not seal the block. I would appreciate feedback on this plan.
Can I also put double-sided reflective insulation underneath across all the joists? It's for a cabin crawl space, so there isn't a cement foundation. I like the idea of reflecting radiant heat. And that could hold up the pink insulation better than those little metal rods. But could critters chew through the reflective insulation? Would I be better off using panel board and tyvek underneath that? Or panel board with reflective insulation underneath that?
Never use the pink stuff/fiberglass in a basement. Critters will nest in there and it is not resistant to moisture/mold/mildew. If it is an unfinished basement, the radiant bubble foil alone works wonders and you can use a can of spray foam (Great Stuff, Dap, etc) to seal cracks and small holes first. Avoid this closed or open cell spray foam madness like the plague. I wish these guys would stop making these videos and convincing homeowners this is the thing to do. Not too far down two road we will be seeing new videos on the effects of the toxicity of this stuff much like asbestos and lead.
Thanks for the video. I have an older house where the floor joists sit directly on a concrete block foundation. I’d like to spray foam the rim joists, but should I spray over the openings in the blocks? I was told those should remain open to allow moisture to escape if needed. Thanks again!
Great video, thanks. Could you tell me if this is right - I read that you have to keep actively spraying the system 600, every 30 seconds or so, or it starts to setup in the nozzle... For me, a DIY'er working alone, this is going to be a challenge. Moving ladders, tanks, etc.; Thanks! Scott
Your taking about inside rim joist only. What about exterior. I have an open porch and water has rotten some spots. Should I use a rubber coating? Or does it need to breath.
Very helpful video. What about the old adage that old houses need to breathe, that sealing rim joists will stop air flow throughout the house, from basement to attic? Would love to hear your thoughts on that since we have an unfinished basement with stone foundation, pretty cold in winter.
I think the origin of this one may lie in the supertight, superinsulated houses of the 1970s, when they hadn't yet figured out how to look at the house as a system. They sealed up the houses to eliminate all the energy wasted on infiltration, but they forgot one key detail. Tight houses need mechanical ventilation. . Here are the three main problems that sometimes occur with tight houses: Poor indoor air quality Backdrafting of combustion appliances High humidity, mold growth
Wouldn't close cell spray foam prevent the wood from expelling any moisture that it adsorbs from the outside? Like if its humid outside and dry inside the wood would just saturate?
How do You Recommend Sealing a Cell Opening? I have an Older Home 1865 I have a Hand Laid Foundation, with a Brick wall built in front of it. So I have the gap between the foundation & brick wall.
I am in Chicago and have an old 1800's era stone foundation home with fireblock in my rimjoist areas. There is clear moisture intrusion and minor deterioration of the joists in this area. Is there a specific method you recommend for this situation?
Same thing on my 100 year old home ( Except I have an earlier form of concrete). you need to remediate as much water as you can outside first. That might involve rerouting gutters to dry wells (at least 10 ft away)and then sealing your exterior foundation. After that, the world is your oyster. Double check your foundation from the inside with a moisture meter and then go to town with whatever insulation you feel fit. You are going to be shooting for as low of a moisture content is possible and after you seal your exterior I would recommend running a dehumidifier for several weeks and getting it as dry as absolutely possible. Crispy dry. Then you can also seal your foundation from the inside, do your foam and whatnot. You will need about 3* the product just for the simple fact that your foundation is going to naturally have more gaps, cracks, and intrusion points, especially on the exterior.
what you show in the video is a fairly deep joist above the concrete runner. in my home i have maybe 1/2-1" of exposed rim joist before im just right into the basement ceiling. i think they filled it all with wood when the house was built in 1890. i want to add more insulation so... would spray foam and then solid paneling applied to it while wet work to ensure no air gaps on the back side but still conform to the uneven concrete/wood thats in my joist areas? trying to keep costs down on materials. if i were to spray foam the whole thing i think id need to add runners under the joists to make at least 2" of 'tunneling' for the foam to fill?
If I seal the rim joists what provision should I make to bring in air for our gas furnace? I'm guessing that at this time there is more than enough combustion air leaking in.
Great info! I have some HVAC ductwork that is close to the rim joist. Is the material from any of these methods able to come in contact with the ductwork?
We have a crawlspace that is about 3 feet high under our house. Is it sufficient to just spray the rim joists? The foundation itself is cinder block. I can't imagine cinder block would have much of an R value. Thoughts?
From a planning perspective, how efficient if a first time sprayer? Im looking at a 600 foot sprayfoam kit? How likely will I be able to cover 210 liner feet 2 inches thick for a newbie? I can do the math, So I know 600/2 inches is 300 square feet 2 inches thick. But I don't know the percent of waste and common mistakes that newbie will make. House if 15 years old.
What about bugs or termite infestation inspection? How do you inspect without removing all that stuff? I've ran into problems with bugs and would not know if was all sealed in and hidden. New construction yes, but retro not so.
I am planning to spray Froth-Pak foam on my rim joist and part of the joist has an electrical wire attached to it that runs into an upstairs bedroom. Anyone know if it is ok to spray over that wire?
Good info as always. ty. Question: Do you need to apply a fireproof coating over the spray foam like a DC315 if the basement is finished? What about a 'semi-finished' area in a basement like a laundry room, etc.? thanks
I have a block wall basement foundation (not crawlspace) and I have floor joists and rim joists directly on the block wall. No sill plate. So the top of the block is open. Exterior is brick btw don't know it that matters. How should I seal the top of the block wall? I was thinking spray foam in a can for the top layer of block openings since it would be difficult to fill with cement. Any reason not to use foam inside the top layer of blocks?
Thanks for the video. Would closed cell between the floor joists (not the rim joist) help with potential creaks in the floor down the road or is it a potential for problems with the floor expanding and contracting?
Absolutely! I'm just waiting until all of these new buildings are about 30 years old and start needing actual repairs, and people figure out that the servicability of spray-foamed structures is difficult at best. Of the 3 methods shown, flash&bat would be my preference from a maintenance perspective for elec/plmg/hvac, since the foam is just a light coating to create a seal. The foam board is the other choice, again it can be removed or cut out if access is needed. Spray foam just makes a mess, especially when pipes and wires get covered with it.
@Dwight Bennett I absolutely see your point for serviceability, I would just dig out the form and do what I had to do to relocate the pipes. The flash n batt method would be a much easier approach but you would have to replace the insulation in any of the methods. I often see service contractors take out insulation haphazardly do the repairs and then half ass trusty insulation back inI absolutely see your point for serviceability, I would just dig out the form and do what I had to do to relocate the pipes. The flashing back method would be a much easier approach but you would have to replace the insulation in any of the methods. I often see service contractors take out insulation haphazardly do the repairs and then half ass toss that insulation back in. Bottom line the insulation has to be put back in with as much hair as it was originally installed which means it probably will need to be replaced if you want it done correctly
I did flash and batt on our 1929 house in Alberta Canada. This was 7 years ago. Street noise, heating bills, indoor comfort all improved. Total foamed homes are great, I would foam the entire home these days
I did the rigid foam board with spray foam around the edges to insulate my rim joists however, there's about 4 inches of cinder block exposed at the top of the foundation before my sill plate begins. I'm debating leaving the cinder block exposed because there aren't any holes or cracks where air is coming in. However, the blocks are cool to the touch. I live in Minnesota so they can get kind of cold. How important is it I cover that cinder block? I've already sealed the seam where the sill plate meets the foundation. Thanks for your videos
I read you shouldn’t use the rigid board without the batt on top due to fire hazard. Is that accurate? I’ve seen so many videos where they just use the foam board
@@ConcordCarpenter ok, there are quite a few places air is coming in, could I seal those spots up with foam or caulk , then add the rigid board, then foam the edges again
Awesome break down. So much better than anything I have read in an article online. Thanks!
Mr. Concord Carpenter. As a widow I've been trying to maintain my home for the past 8 years. My next project is to insulate my cellar sills. Thank you very much for sharing your knowledge. I now know how to do this. It will probably take me a long time to get it done but that's ok. I can do this! Thanks again!
I feel your pain! I’m right there with you! Sometimes I feel like the widow in the movie “What Dreams May Come” stuck in my house with SO much to do now, but WE CAN DO IT!!
Just skip the spray foam against/touching any exterior wood membranes though.
My husband was a Forensic Structural Engineer and had tons of inspections where there had been a leak of some kind, but the spray foam concealed it so well, it rotted the wood from the inside out. 😳🤦♀️
Maybe stick with using EPS FOAM BOARD cut to fit each rim joist area and then just use can of spray foam to seal around the edges.
Have faith!🙏 Be strong! 💪
Good luck & big hugs to you!! 💛
@g quin Once the foam cures your fine. While wet and until cure, ventilation and carbon filter/APR.
Most women don't realize and appreciate how valuable is a man around the house till they lose him. God bless you in your projects
Speaking as a 25-plus-year widow--since I was 43--I could say the same for the reverse, Adrian.
While my husband was a brilliant "thinker," he absolutely DESPISED performing vehicle and/or home maintenance duties. As a "stay-at-home" mother-of-four, those responsibilities were almost exclusively mine.
@@martinabsp5327 Absolutely. Skills and the desire/motivation to perform them are genderless. Your children are lucky to have your example whether they are boys or girls.
That is exactly what i just found behind the fiberglass bats. Thank you!
This is a great reference! I have been working on my house's addition crawlspace which I have been working on since buying it fixing all the previous owners issues. This is EXACTLY the kind of guidance I was needing for how to properly and effectively insulate the rim joists. Thank you!!!
Glad I saw this before replacing my basement insulation. Liked the comment about leaving gaps around foam board and using small wedges to keep space to get spray foam around the edges.
In most of Canada, previous practice was to just place batt insulation in the joist cavity. Then it was required to have batt insulation with poly over, with the poly just stapled in place. Then the poly needed to be sealed to the joists, usually with acoustical sealant. Then spray foam, just spray foam became best practice. Now the spray foam needs to be also protected from fire with drywall in most municipalities. I regularly perform air leakage tests on new homes (blower door) and we still find that the spray foam leaks air. Not many people realize that air leakage of a home is a far worse issue that lack of or improperly placed insulation. Spray foam alone, is NOT the perfect solution.
Then what is?
@@moritzin1 There is NO perfect solution.
I am just fixing my house’s rim joists in Canada and I found exactly that - just insulation bats slapped in. Built in 1977
Great video! It’s important to note that the installer you show in this video is not wearing the proper respirator for spray foam. Dedicated outdoor air supply should always be used during installation. I have also not done this correctly in the past, but know better now. Keep up the great work!
Actually this is a Froth Pack not a PRO high psi spray system and requires wearing a NIOSH approved organic vapor air purifying respirator with a particulate filter if the exposure to pMDI is unknown or in doubt, especially when spraying where ventilation is limited such as in crawlspaces or where spraying close up. This space was well ventilated with fans.
With a PRO system - yes you are correct typical best practices with supplied air
@@ConcordCarpenter I am not involved in installations anymore, but recently have heard that outdoor air supply should be used with pro systems and froth packs. I can't remember the source at the moment. Anyway, I would look into it to make sure.
Even Rob's technical specs do not subjugate your point, excellent always wear respirator & have massive ventilation
This is a very helpful video. I started insulating my rim joists a few weeks ago using foam board (r10) and spraying canned foam insulation around the perimeter, while this is time consuming and tedious at times it's coming along. I checked the temperature between a section that was sealed and one that was not, the insulated section was 10 degrees warmer (55 vs 65) while it was in the teens outside. The spray foam insulation is lethal and yes you should wear a mask, once it's dry you don't have to worry about breathing in the fumes. Once everything is sealed I plan on using un-faced Rockwool R-15 to fill in the gaps, based on my research this would work best. I had no idea what to expect when I started this but the fiberglass batts that I pulled out were filthy and covered with bugs, in one joist I found a live hornet, thankfully it was sleepy and slow. In other sections there were live stink bugs and ladybugs (lots of them) There are corner sections that are very tight and I will have no choice but to spray foam into them. I'll be glad when it's done. As far as the brand used in this video and by this Concord Carpenter, maybe that's what he uses, who cares, educate yourself on what would work best for you.
I am thinking of doing the same method in my basement. On the rim joist ends in my house they're cement. The joists are set down into the poured cement foundation. Would love to hear further how your project worked out and if you had pictures to share of the finished process that would be awesome.
hey friend, how did it turn out? I'd like to try the same soon.
Thank you for this. We had our first winter last year in a house we bought, the floor was def cold and it was made in the late 80's. All they did before with the last owner was BAT insulation in the basement for the Sill/rim joists. I was going to do rigid foam boards and then seal them but the benefits of the spray foam I like better. Plus it'll go a lot faster.
You have to make sure you take the time to vacuum and clean out those rim-joints first. So many times they can filled with old insulation, plaster dust, brick dust and just all sorts of debris. I believe you can even take a spray bottle of water to misty area really good, before applying the spray foam.
@g quin Once the foam cures your fine. While wet and until cure, ventilation and carbon filter/APR.
the foam they are using does not need water it is two part foam that reacts with each other and will harden much better than the cans of spray foam but they are a pain to use if one side comes out more than another it will not work and the hoses and tips get clogged if you stop for too long.
Best information I have ever found on the subject. Thank you
I knew all those off-cuts of 2 inch rigid foam board I've been hanging onto were going to come in handy. Just recently picked up some of those DAP spray foam cans and an applicator too. I've seen my future, and it involves lots of cutting foam board, swearing, and more cutting. Thanks Concord Carpenter, for always pointing the way. Fantastic content as always.
It’s like we’re living the same beeeeeeeping DIY life. 🤦♀️
@g quin Once the foam cures your fine. While wet and until cure, ventilation and carbon filter/APR.
Just came across this video and your basement foam board insulation video while starting this project myself. Very useful and great explanations! Thank you very much!
Awesome, thank you!
Spray foam will provide a nice environment for mold as easily as improperly installed batt insulation and vapor barrier.
I've done Renos on many new homes only a year or so completed that had moldy, cracked spray foam.
All these methods require true craftsmanship and care in order to function as required.
I have had well over a decade of experience with every possible technique.
In my experience, batt insulation and vapor barrier are superior when installed by somebody who truly values their work.
The problem is getting someone who does take proper care with the work... I end up doing a lot of things myself because I just can't get anyone else. If I can't do it myself, it doesn't get done. 😢
@@maaismak8915 building inspectors also need to be held responsible for consistent blind eye turning.
Would be nice to filter out the hacks, so the real tradespeople can get the work done.
2/28/22; insulation...yur video 2day was one of your best/most practical videos. Don't stop your insulation education & presentation to all us YT armchair viewers & weekend handymen. Continue along with more info. New construction: after stud wall framing, Zip green wall exterior sheathing, & brown roof sheathing. Each of these painted osb boards has 2-part poly-iso foam insulation glued to interior side. You can get different thickness of the foam on these boards made for your area of country...extreme cold or hot. But you are not done! Gotta seal (special black tape, rolled/pressed tightly or special black caulk spread, mini troweled into) all those seams of the 4x8 sheets + put same black sealer all around your window & door openings. Their is lots more on this insulation & air infiltration, moisture (&bug) control issue, but you will decide how much you want to present to your viewers.
Oh yes, Happy Mardi Gras from (chilly 40°) New Orleans area! Green/brown board, black caulk/tape, poly-iso foam stud spray & blower door tested areas all over US & Canada. Enjoy your channel & testing comparisons for tools...maybe now some insulation comparisons & testing too?🤔👍👍👍🧑🔧🍺
Something about Rob's presentation makes me motivated to do this fix. Oh, nevermind I have slab-on-grade. Great video though. Be sure to wear your respirators ya'll.
Great video. You sure convinced me not to use rigid foam board on rim joist around our 1800sf space. Wish our workshop looked so good!
Well, I see I'll be removing the old punk stuff and getting foam boards. Thanks for the video!
Thanks Ron you got a great show in a well experienced carpenter never stops learning with you
@g quin Once the foam cures your fine. While wet and until cure, ventilation and carbon filter/APR.
I cut and screwed in my R5 tinfoil foam insulation with 2" screws and large washers to fill in all these rim joists areas. I then can spray foamed all around. Good advice to cut 1/2" small. Yes, it takes time. But the comfort, temperature, energy use difference was felt immediately by the whole family when I finished installing an R35 sealed plate of insulation under the whole footprint of my century old house. I can sprayed foamed every seam and junction and then cut it flat when dry before carefully taping the aluminum tape. I also put two 2" layer of tinfoil foam board against the perimeter concrete walls being here in Canada.
Flash and batt!! It can also at shear value if closed cell is used. It's a great method.
@g quin Once the foam cures your fine. While wet and until cure, ventilation and carbon filter/APR.
@g quin So does sawdust. Mold isn’t exactly good for you either.
I bought a fixed upper cause there are a lot of things I can already do. This winter I had some frozen water pipes (primarily due to the previous owners short cuts). While I'm not yet confident I could do the full spray foam, I will opt for the foam board and seal. Good vid. Thanks
Very good!!! Every ''DIY home owner's'' should watch this video. I have have studied a lot and a lot to do that by myself the right way. I really wanted to have a 100% understanding of the science behind that because i have seen a lot of bad ways to do that on internet. That's a very GREAT video. The way you are talking about what's happening with the materiel is really cool because if the temparature where i live is different than your's, i can made little ajustment the right way. Thank you!!!
Wow, thanks!
Having had this done a little over a year ago upon the recommendation of an air-sealing company, I can say spraying with closed-cell foam has some major drawbacks: It never can be removed if necessary, makes termite inspections impossible from the inside and hides termite damage, makes hunting for leaks impossible, traps water against the wood framing being closed-cell foam if leaks develop which will promote rot. With these observations in my home, I'd caution against it. If anything, I'd suggest using foam to seal cracks and then use bats or foam board. Keywords in the video are quick in and quick out which is exactly what this company I chose did and cut corners which I now regret and will have expensive mitigation in the future.
Exactly! Spray foam insulation is the "new rage" and it is a Gd awful mess. Carcinogenic chemicals and impossible to ever fully remove. Tell me why the installers need to be in full hazmat suits but the homeowner or renter is fine to breathe it in over years? Does it somehow become inert once it hardens? No. No, no it doesn't. Also, find me ONE electrician or plumber that likes this stuff...you are literally hardening all wire and pipes inside this foam. Watch all these videos on YT. It's insane. I can't even fathom why these guys can just do this and not think about the future. There are far better materials for basements that are mold resistant and rodent proof and for walls nd attics above ground. Please stop this spray foam madness.
sorry to be so off topic but does anybody know a tool to log back into an instagram account?
I somehow lost my login password. I love any help you can offer me.
@Ronnie Sullivan instablaster ;)
@Enrique Charles Thanks so much for your reply. I found the site thru google and im in the hacking process now.
Seems to take a while so I will get back to you later with my results.
@Enrique Charles It did the trick and I finally got access to my account again. Im so happy:D
Thanks so much you really help me out :D
Many thanks for your insight. Had a generator installed and those electricians really suck at putting the insulation back and now 25% of the house is ice cold because the bans joist where they installed a couple pipes are icy cold all winter and the floor is icy cold. Was trying to fix it with all kinds of ideas but flash and batt will work for me. I have the batt. Just have too much outside air penetrating the cavity.
Rob,
Thanks for sharing your knowledge and expertise 🤟🏽
I just insulated the rim joist on my house in southwest Ohio. I used caulk to seal the gaps the R-15 mineral wool. The reason I did not use foam board or spray foam is that the house may need a termite inspection in the future and the mineral wool will be easier to take out and put back.
The problem is that the mineral wool, like fiberglass is air permeable. Therefore, you risk moist air passing through it and condensing on the cold rim joist.
@@percyfaith11 I'll keep an eye out for that. I had to remove one piece after the first winter to fix a pipe. I saw no problems. With closed cell foam or rigid foam boards I would be worried about moisture passing through the wood from the outside then condensing on the inside and having no way to evaporate. Caulking the seams all around is very awkward and difficult but that step alone probably gives a huge benefit since it stops the air transfer.
@@chuckhall5347 Chuck, in the winter the inside of that wood is warmer than the outside, so there won't be any moisture condensing on the inside of the wood that comes from the outside. Besides, in winter, the outside air is extremely dry, if you live in a northern climate. It's only inside humidity, generated by breathing, cooking, etc, that can get to the cool inside surface of the rim joist and condense.
Unless the rim joist is continually soaked in water, humidity won't go through solid wood just from being water vapor in the air.
Just gotta say thanks now I have better understanding of this part. And need to find best way for me to do the job and fastest n cleanest. Think I’ll do a mix of 2/3 of these. Tight area 2inch spray and then foam board with spray foam in others.
The video should say, you MUST wear the right respirator when installing spray foam. You can have serious lasting health problems caused by a single application with improper protection.
@g quin Once the foam cures your fine. While wet and until cure, ventilation and carbon filter/APR.
@@hklilly4854 what is the correct type of respirator for installation?
Nicely explained. Much appreciated and many thanks.
Super good video. This guy knows.
@g quin Once the foam cures your fine. While wet and until cure, ventilation and carbon filter/APR.
Great info. Thank you
Glad it was helpful!
If the rigid insulation is also the vapour barrier, shouldn’t the fibreglass insulation be installed first? Why would you treat this area differently than the rest of the house, that is, vapour barrier on the warm side?
Edit: What should be done with the exposed concrete by the sill plate? Foundation 10” thick with a 2x6 sill plate leaves you about 4” of exposed, cold concrete.
I did the 2" rigid foam board with can foam around the edges, and then batt insulation, for a 2700sf house, so not a big basement. All I gotta say is, be prepared to spend a LOT of time in the basement sticking your head between the joists. The spray foam option for rim joist air seal/moisture barrier is worth the extra money.
Timesaver
I did the same on my 1400sq ft basement. I thought it was well worth it. Cheap material cost, and once I got in the groove it went in fast. Probably was at it for 8-10hrs spread out over a few nights. Thermal imaging camera showed it sealed nicely.
When compared to spray foam cost, the possible health risks, and the requirement to vacate the house for 24hrs due to fumes, it was a no brainer.
What can foam for edges?
This is GREAT! Very concise and informative. No waste of time here.
Thanks for the knowledge, Rob !!!!!!!!!!!
Awesome video, as usual! Here in Canada, Newfoundland to be specific, we always need vapour barrier. I believe due to the climate, vapour barrier is not necessary in some parts of the US. Ours is typically plastic (poly comes in rolls) on the warm side of the insulation/wall system - between the studs and gyprock. It sounded like you were indicating that the rigid insulation or foam placed on the sill (cold) beam would act as the vapour barrier. It could then be added to with rigid, foam or fibre glass insulation. This seems nearly opposite to how we do it. I understand that different climates call for different best practices. Some places put the barrier in different places within the system. Flordia would be very different from here I suspect. The continuity of the vapour barrier throughout the house is also very important here. Love your content! Please keep it coming!
as long as drying potential is on both sides of the foam you should be fine. If you had a foil face insulation on the outside or another vapor barrier inside of the foam then that would cause issues. If worried about the vapor barrier on the foam peel off the plastic film. Personally I would just caulk the seam for air seal and then use rockwool insulation
The vapour barrier needs to be on the warm side of the air space. With batts or loose fill that's just under the finished wall surface, usually drywall, because moist air can move through the insulation. That means the vapour barrier will stay above the temperature where moisture will condense. With closed cell foam, the air can't move through, so you only need to make sure there is no air space where it meets the cold surface. In this case, any condensation will be on the outside of the sheathing and can dry to the outside.
Great video. Thorough explanations for noobs like me.
Glad you enjoyed it!
Very informative, Rob is the kind of guy I would have a beer with.
Love the content as always!!
Thank you
@g quin Once the foam cures your fine. While wet and until cure, ventilation and carbon filter/APR.
Great video and explanation!!!
Great info...for a girl trying to DIY :)
Hey, Rob! Would love if you would do a video on how to find studs in a wall when it's hard to find things that reveal it's position, eg. behind standing wooden panel.
Interesting - thanks
@g quin Once the foam cures your fine. While wet and until cure, ventilation and carbon filter/APR.
Perfect! Answered the exact question I had.
Really good info. Thanks 👍
I was wondering if I should use my leftover XPS board to replace that blackened fiberglass bat. Now, I'm 60/40 going to use it, just needing more research about vapor barrier wooden rim joists should that exterior moisture be retained within that wooden rim joist; won't it accelerate rot?
When they built mine the trusses were inset 1” n then a band of foam around the outside. Hope it was adequate start.
I understand what the experts state. I just can't wrap my head around that they're saying there is MORE moisture getting behind a much colder, unconditioned cellar batt (if sealed properly) compared to a 70/76 degree conditioned space with batt walls? 🤔
Thank you for a video with footage that is nearly identical to my situation. I have openings in the cinder blocks at the top that are extremely drafty in our Wisconsin winters. I'm leaning toward 2-part spray flash and batt method vs the other options. Instead of fiberglass batts, I'd use Rockwool batt insulation after spraying Dap foam. 2" spray foam along with a tight fitting batt of R 15 Rockwool should give me plenty of R value. Rockwool is also an additional fire barrier. Here is my question: Is it advisable to stuff the open cinder block cavity with some rockwool batt then 2-part spray in the rim joist area and over the cinder block filled cavity? I'm concerned that the cavity is just too wide for the foam to fully seal on its own. Thanks again. 😊
I always understood that you vapour barrier on the warm side of insulation, that if it's sealed on cold side moisture will condense between insulation and vapour barrier . We get temp to -45 and can feel cold on floor perimeter , it's insulated with 2" of styrofoam rigid between joists but I'm thinking of spraying over and sealing the ends of the joists . You seem to advocate sealing the rimboard then styrofoam inside
Very helpful info! Recently purchased an older home with unfinished basement/garage that is also home to gas water heater, furnace and most household plumbing. I'd like to provide some insulation, but do not want to cover the cinder block walls as I prefer to keep them visible in the event of future problems. Would insulating only the rim joist with spray foam be beneficial?
the rim joists are much more important than the block walls if the walls are underground, they don't lose as much to ground as the top sill area to outside air you can dump Styrofoam peanuts or vermiculite in top of block wall openings for insulation inside i tried perlite that stuff is awful if you breath it in you need a good respirator. then when you get near top seal the top of block wall with some Spray foam in the openings.
I hate those froth packs with a passion we used them at work, and they would get clogged all the time one side of mix would clog and you would get a mess.
Stopped using fiberglass insulation completely. Use rockwool exclusively, which is way better insulating and fire block. Really do not like using spray foam. it is messy, looks like crud, and not forgiving of mistakes. The other issue, is sprayed right against the wall, it eliminates any air space, and can be a cause of moisture retention, then mold. I typically put up bead board, against the wall, between the studs, which then a vapor barrier, waterproof liner over the bead board, then rockwool, then 5/8" sheetrock. This is labor intensive, but the results, quality is worth the effort.
I understand the flash-n-batt for the rim joists and between joists but what about exposed cinder block wall below it? Should I install foam board and/or treat with drylok?
Hey guys, schoolboy question from me.
Doesn’t something like this raise concern?
Say you have below you have a timber floor, and between the sub floor and downstairs ceiling plasterboard, between the cavity you already have rock wool insulation, and now you are sealing the gaps around the joist-to-plasterboard…
Shouldn’t you leave some gaps for airflow?
If you cover the sill and rim joist with foam, won't the moisture within the concrete walls eventually find its way to the sill plate and then the rim joist, causing them to rot?
A reasonable question. See my observations as well.
Great video! question about rigid board. Why 2 inches? is 1 inch R-5 not enough to create an air seal?
Wow, this is great, ok, it’s system 600 for me.
Thank you
You're welcome
Fiberglass baths are also good for rats and mice to nest. I pulled some down and found a bunch of mouse droppings. Im ripping it all out and re doing it!
What do I do if I don’t have a sill plate? My joists are sitting right on top of the poured concrete wall. Thanks for the video!
@g quin Once the foam cures your fine. While wet and until cure, ventilation and carbon filter/APR.
I would think you'd have to put foam board on the top of the concrete wall between the joists. (In my previous house the top of the basement's concrete block wall didn't have a sill plate either. I was surprised when I first saw it.)
Hey Rob, thanks for taking the time to make your videos. They've been very simple to follow. I have a question about proper insulation in a catilevered bay off of my kitchen doorwall. Very cold floor there in the kitchen during the winter. I can access it from the basement (conditioned space below). wondering which surfaces should get rigid board or spray foam in the cantilevered space. Thanks for any help you can provide. Im in Michigan If that helps better understand the climate. Thanks again.
@g quin Once the foam cures your fine. While wet and until cure, ventilation and carbon filter/APR.
As a retired insulator who had 23+yrs in the trade, I found that foam board pieces at the perimeter ( as in the non- cantilevered rim area), then another piece of foam board flat on the area FROM perimeter rim to the sill board at the top of the block wall, then sealing all edges of the rigid foam with spray foam( great stuff or gun foam) works the best, and meets code in most cities.
This allows warm air to circulate in the space between the bottom off the cantilever and subflooring above, thus keeping that area warm
great info
I'm getting ready to encapsulate my crawl space. The foundation cement block is porous. The contractor claims that leaving this space will negate the effect of the encapsulation and he will not guarantee the work if he does not foam over the entire foundation. I have decided to paint a couple coats of masonry waterproofing paint on the top 6-8 inches of the foundation block just below the sill plate and placing the foam starting 4 inches below the sill plate. It should maintain encapsulation and provide an inspection "window" for termite tubes. In theory, if you do not leave the space termites to gain access to the wood from behind the foam. There are a few videos showing the value of keeping this area exposed but they do not seal the block. I would appreciate feedback on this plan.
@g quin Once the foam cures your fine. While wet and until cure, ventilation and carbon filter/APR.
Great info, Thanks!
Glad it was helpful!
Can I also put double-sided reflective insulation underneath across all the joists? It's for a cabin crawl space, so there isn't a cement foundation. I like the idea of reflecting radiant heat. And that could hold up the pink insulation better than those little metal rods. But could critters chew through the reflective insulation? Would I be better off using panel board and tyvek underneath that? Or panel board with reflective insulation underneath that?
Never use the pink stuff/fiberglass in a basement. Critters will nest in there and it is not resistant to moisture/mold/mildew. If it is an unfinished basement, the radiant bubble foil alone works wonders and you can use a can of spray foam (Great Stuff, Dap, etc) to seal cracks and small holes first. Avoid this closed or open cell spray foam madness like the plague. I wish these guys would stop making these videos and convincing homeowners this is the thing to do. Not too far down two road we will be seeing new videos on the effects of the toxicity of this stuff much like asbestos and lead.
Thanks for the video. I have an older house where the floor joists sit directly on a concrete block foundation. I’d like to spray foam the rim joists, but should I spray over the openings in the blocks? I was told those should remain open to allow moisture to escape if needed. Thanks again!
Great video, thanks. Could you tell me if this is right - I read that you have to keep actively spraying the system 600, every 30 seconds or so, or it starts to setup in the nozzle... For me, a DIY'er working alone, this is going to be a challenge. Moving ladders, tanks, etc.; Thanks! Scott
Do you need to install fiberglass installation over Rigid?
no you don't need too but you can't if you wanted to help increase the total R value.
Can that spray foam go on ridged foam or would a chemical reaction happen
Your taking about inside rim joist only. What about exterior. I have an open porch and water has rotten some spots. Should I use a rubber coating? Or does it need to breath.
Very helpful video. What about the old adage that old houses need to breathe, that sealing rim joists will stop air flow throughout the house, from basement to attic? Would love to hear your thoughts on that since we have an unfinished basement with stone foundation, pretty cold in winter.
I think the origin of this one may lie in the supertight, superinsulated houses of the 1970s, when they hadn't yet figured out how to look at the house as a system. They sealed up the houses to eliminate all the energy wasted on infiltration, but they forgot one key detail. Tight houses need mechanical ventilation.
. Here are the three main problems that sometimes occur with tight houses:
Poor indoor air quality
Backdrafting of combustion appliances
High humidity, mold growth
Wouldn't close cell spray foam prevent the wood from expelling any moisture that it adsorbs from the outside? Like if its humid outside and dry inside the wood would just saturate?
How do You Recommend Sealing a Cell Opening? I have an Older Home 1865 I have a Hand Laid Foundation, with a Brick wall built in front of it. So I have the gap between the foundation & brick wall.
No fire protection on the foam?
I am in Chicago and have an old 1800's era stone foundation home with fireblock in my rimjoist areas. There is clear moisture intrusion and minor deterioration of the joists in this area. Is there a specific method you recommend for this situation?
Same thing on my 100 year old home ( Except I have an earlier form of concrete). you need to remediate as much water as you can outside first. That might involve rerouting gutters to dry wells (at least 10 ft away)and then sealing your exterior foundation. After that, the world is your oyster. Double check your foundation from the inside with a moisture meter and then go to town with whatever insulation you feel fit. You are going to be shooting for as low of a moisture content is possible and after you seal your exterior I would recommend running a dehumidifier for several weeks and getting it as dry as absolutely possible. Crispy dry. Then you can also seal your foundation from the inside, do your foam and whatnot.
You will need about 3* the product just for the simple fact that your foundation is going to naturally have more gaps, cracks, and intrusion points, especially on the exterior.
it is the best insulation spray foam, but it is very bad for wood to recycle.
what you show in the video is a fairly deep joist above the concrete runner. in my home i have maybe 1/2-1" of exposed rim joist before im just right into the basement ceiling. i think they filled it all with wood when the house was built in 1890. i want to add more insulation so... would spray foam and then solid paneling applied to it while wet work to ensure no air gaps on the back side but still conform to the uneven concrete/wood thats in my joist areas? trying to keep costs down on materials. if i were to spray foam the whole thing i think id need to add runners under the joists to make at least 2" of 'tunneling' for the foam to fill?
I worry about insulating over the rim joist because then I wouldn't see the wood rot if it does. What's wrong with my thinking?
Seems to me that foam board installed with spray foam around the edges would be better for those times you need to remove it to inspect the joists.
Yep
I have to dig small trench because close to the ground .. There is thin foam board n strapping but its old n falling apart n starting to get rodents
If I seal the rim joists what provision should I make to bring in air for our gas furnace? I'm guessing that at this time there is more than enough combustion air leaking in.
Check with your plumber to see if you need it. There are systems you can add, some furnaces already have it
Great info! I have some HVAC ductwork that is close to the rim joist. Is the material from any of these methods able to come in contact with the ductwork?
what about you being flex seal in a spray can then batt or rigid board?
We have a crawlspace that is about 3 feet high under our house. Is it sufficient to just spray the rim joists? The foundation itself is cinder block. I can't imagine cinder block would have much of an R value. Thoughts?
Yes spray foam the walls, is the floor dirt?.. read this. www.aconcordcarpenter.com/tag/encapsulating-crawl-space
What about insulation in a basement with the waterproofing drainage membrane on the inside? Old house and not possible to waterproof from the outside?
From a planning perspective, how efficient if a first time sprayer? Im looking at a 600 foot sprayfoam kit? How likely will I be able to cover 210 liner feet 2 inches thick for a newbie? I can do the math, So I know 600/2 inches is 300 square feet 2 inches thick. But I don't know the percent of waste and common mistakes that newbie will make. House if 15 years old.
What about bugs or termite infestation inspection? How do you inspect without removing all that stuff? I've ran into problems with bugs and would not know if was all sealed in and hidden. New construction yes, but retro not so.
For the rigid foam board installation why not use the spray foam as a bonding agent instead of glue?
That works
How do you handle areas with obstructions , such as water pipes running up though the wall?
I am planning to spray Froth-Pak foam on my rim joist and part of the joist has an electrical wire attached to it that runs into an upstairs bedroom. Anyone know if it is ok to spray over that wire?
Its ok
@@ConcordCarpenter Thank you, great video by the way!
Good info as always. ty. Question: Do you need to apply a fireproof coating over the spray foam like a DC315 if the basement is finished? What about a 'semi-finished' area in a basement like a laundry room, etc.? thanks
I have a block wall basement foundation (not crawlspace) and I have floor joists and rim joists directly on the block wall. No sill plate. So the top of the block is open. Exterior is brick btw don't know it that matters. How should I seal the top of the block wall? I was thinking spray foam in a can for the top layer of block openings since it would be difficult to fill with cement. Any reason not to use foam inside the top layer of blocks?
Would this help if I get water running down basement wall from rim joist do to heavy rain fall. Thanks
No you need to remedy that first
Thanks for the video. Would closed cell between the floor joists (not the rim joist) help with potential creaks in the floor down the road or is it a potential for problems with the floor expanding and contracting?
Great question - it’s basically glued to the subfloor, I’m questing it would
What happens when you have spray foamed pipes and wires and then they require service? Is there an added cost to cut them out and then reinsukate?
Absolutely!
I'm just waiting until all of these new buildings are about 30 years old and start needing actual repairs, and people figure out that the servicability of spray-foamed structures is difficult at best.
Of the 3 methods shown, flash&bat would be my preference from a maintenance perspective for elec/plmg/hvac, since the foam is just a light coating to create a seal. The foam board is the other choice, again it can be removed or cut out if access is needed. Spray foam just makes a mess, especially when pipes and wires get covered with it.
of course. Best to plan ahead with your placement of pipes or understand that you might someday have to dig out some insulation to reach the pipe.
@Dwight Bennett I absolutely see your point for serviceability, I would just dig out the form and do what I had to do to relocate the pipes. The flash n batt method would be a much easier approach but you would have to replace the insulation in any of the methods. I often see service contractors take out insulation haphazardly do the repairs and then half ass trusty insulation back inI absolutely see your point for serviceability, I would just dig out the form and do what I had to do to relocate the pipes. The flashing back method would be a much easier approach but you would have to replace the insulation in any of the methods.
I often see service contractors take out insulation haphazardly do the repairs and then half ass toss that insulation back in. Bottom line the insulation has to be put back in with as much hair as it was originally installed which means it probably will need to be replaced if you want it done correctly
@@ConcordCarpenter On point
I did flash and batt on our 1929 house in Alberta Canada. This was 7 years ago. Street noise, heating bills, indoor comfort all improved. Total foamed homes are great, I would foam the entire home these days
If you use foam board how do you add a fire barrier in an unfinished area?
you can put mineral wool batts over it or fiberglass with vapor barrier and plasterboard if you want or just plasterboard right over foam.
I did the rigid foam board with spray foam around the edges to insulate my rim joists however, there's about 4 inches of cinder block exposed at the top of the foundation before my sill plate begins. I'm debating leaving the cinder block exposed because there aren't any holes or cracks where air is coming in. However, the blocks are cool to the touch. I live in Minnesota so they can get kind of cold. How important is it I cover that cinder block? I've already sealed the seam where the sill plate meets the foundation. Thanks for your videos
Cover with RIDGID or stuff with mineral wool
My understanding is that many areas require several inches of exposed foundation inside your crawl space for termite inspection.
@@tylern3696 I do what I want in my own house
Hello, I'm wondering what you think about using a mold inhibiting primer like KILZ on the joists/sills prior to foaming and sealing?
I read you shouldn’t use the rigid board without the batt on top due to fire hazard. Is that accurate? I’ve seen so many videos where they just use the foam board
dont think so
@@ConcordCarpenter ok, there are quite a few places air is coming in, could I seal those spots up with foam or caulk , then add the rigid board, then foam the edges again