40-odd years ago, I found out that the slab of my house in Las Vegas was poured over a gully that filled with running water every time it rained, and had washed out much of the support for my house. Found this when a 30' hypotenuse triangle of the front left corner cracked and slumped just before I had to sell the house and leave the country. Back then, the quote to pump concrete under the slab to support and raise it was $10K. This is 1983. The house was only worth about $50K at the time. Before the cracked slab. There should be someone in your areas that could fill the space under your slab and save it. But removing it and replacing it might be cheaper. And how I wish I had a garage and slab with a lift on it!
Keep the lift that works. I miss my lift, but can't use one in my tinny detached 12x18x7' (WxLxH) garage. Replace the concrete, make it a UTube vid, write it off, and giggle at the knowledge you just made a difficult job look spectacularly easy in a 15 minute UTube video.
You might be surprised how much load the foam might support that they use to lift and level concrete. Most concrete foundations are poured on top of insulating foam anyway. But it could still be a DIY job renting a core drill, drilling enough holes and pouring in wet runny concrete/cement. You can probably find recipes specifically for this purpose or hire a single standard concrete truck to come out with the right mix to dump in your holes. As long as it’s not an actual sinkhole down there….. A day to drill holes and a day to pour the cement. Would not even have to move things out of the garage.
What I would do: Pump concrete or foundation epoxy underneath. Bandaid? Sure. Better than what you're standing on? Absolutely. Relatively cheap, safe, non-intrusive and can be done in a day with minimal disruption.
Mudjacking sounds ideal, if I could only confirm that my lift is safe on the 3.5” slab. Blows my mind that I can’t find a Benwil manual online in this day and age.
@@thedoubtfultechnician8067 the 3.5" slab has held the lift and various vehicles unsupported for 10+ years, so if it's now mudjacked up, isn't it technically thucker than 3.5"?
@@khoatran9482 I don’t think so. The force is not necessarily downward compression. As the lift gets loaded up the uprights naturally want to bend inwards. It’s these bolts that pull the uprights straight. So it’s a pulling force, and I don’t know that the mudjacking actually bonds to the slab and therefore won’t actually add any additional pull resistance… if that makes sense?
I would jackhammer out the concrete under the lift (maybe 10' x 10'). Get a Harbor freight jackhammer and resell it after your done. Pour a new 6-8" steel reinforced slab in the hole. Reinstall lift. Seal water ingress. If you're really paranoid, drill some holes in the rest of the floor to check for voids.
Get a core drill and cut some inspection holes to get an idea of how extensive a problem it really is. There is a chance the problem is not as extensive as it seems. Maybe you can cut out the mounting areas and pour deep pilings to mount the lift and solve any other issues as they are identified. Just my 2 cents.
If you could find a cheap piece of 1 and 1/2" inch steel plate as long as the lift is wide and wide as the hoist mounting surfaces, you could anchor that to the floor and attach the lift to the plate, but I doubt that you could find a piece of 1 and 1/2" steel for cheap enough (including transport to your shop) to make it cost effective. It would totally solve your hoist problem if you could though.
I would have someone come in and foam level it. If you really feel unsafe with the lift then get a set of quick jacks. The load will be spread out over more area.
I had the same problem in my railway shop…with floor heating. Drilled holes and used sandblasting equipment to blow fill and pack the void. Mud jack company wouldn’t come because of the floor heating
I'd propably just cut out the area, where the lift mounts, maybe like the long irons plus 30cm around it, dig those out deep, genuinely like over half a meter deep, and pour deep point foundations, like if you'd mount a jib crane. To solve the erosion, I'd dig out around the shop, put in water barriers and drainage. If I was feelin really fancy, I'd tear up the poured concrete and replace it with brick pavement, and while im at it, I'd replace the eroded dirt with coarse gravel. That'll allow water to flow through without eroding it.
You’d be surprised how cheap you can get a solid second hand lift from shops that are going out of business or changing locations etc. I had a mechanic that bought a very solid lift for $600 about 15 years back (do whatever inflation calculations you wish)
I would see if you could pump something underneath it to at least stop the water ingress. Then if i had room id look at adding on to the shop, putting a new thick slab in.
Looks like that lift was already modified with 2x2 bars to spread out the weight forward and aft so guessing the installer new it was sketchy at best. What would I do today , not look for info in the comments but get someone who knows what they are doing to look at it. What would 25 year old me do ....... get some 8 ft long 3/8 thick 2x6 angle or square stock and weld the bajezuz out of it wont fall forward or back and make sure the tops of the hoist are held apart with some 2x6 1/8 wall as a spreader. The 5000 ish LB lifting pile of obsolete you can use until you save up to do it right then. Final thought, get it fixed or out before them kids are old enough to be around when its in use or wanting to use it themselves. Peace
Before this it was the roof rotting out and the gutters getting replaced, before that the pipes froze and burst, before that my circuit breaker panel melted… still jealous?
You’re going to have to get in there to see how bad the damage is. And I mean, is it just that area or has it spread to other parts of the garage. That what would scare me.
The workshop is an addition, essentially a different foundation. The main part is built like a tank. If I go the mudjacking route, they use ground penetrating radar to find and eliminate the voids.
40-odd years ago, I found out that the slab of my house in Las Vegas was poured over a gully that filled with running water every time it rained, and had washed out much of the support for my house. Found this when a 30' hypotenuse triangle of the front left corner cracked and slumped just before I had to sell the house and leave the country. Back then, the quote to pump concrete under the slab to support and raise it was $10K. This is 1983. The house was only worth about $50K at the time. Before the cracked slab. There should be someone in your areas that could fill the space under your slab and save it. But removing it and replacing it might be cheaper. And how I wish I had a garage and slab with a lift on it!
Or you could get a couple of 20' sticks of 1"x8" mild steel bar to put under the 2" support bars on the lift... Concrete's probably cheaper! ;)
Keep the lift that works. I miss my lift, but can't use one in my tinny detached 12x18x7' (WxLxH) garage. Replace the concrete, make it a UTube vid, write it off, and giggle at the knowledge you just made a difficult job look spectacularly easy in a 15 minute UTube video.
This, I'd take that lift over a modern Chinesium one.
You might be surprised how much load the foam might support that they use to lift and level concrete. Most concrete foundations are poured on top of insulating foam anyway.
But it could still be a DIY job renting a core drill, drilling enough holes and pouring in wet runny concrete/cement. You can probably find recipes specifically for this purpose or hire a single standard concrete truck to come out with the right mix to dump in your holes. As long as it’s not an actual sinkhole down there…..
A day to drill holes and a day to pour the cement. Would not even have to move things out of the garage.
What I would do: Pump concrete or foundation epoxy underneath. Bandaid? Sure. Better than what you're standing on? Absolutely. Relatively cheap, safe, non-intrusive and can be done in a day with minimal disruption.
Mudjacking sounds ideal, if I could only confirm that my lift is safe on the 3.5” slab. Blows my mind that I can’t find a Benwil manual online in this day and age.
@@thedoubtfultechnician8067 the 3.5" slab has held the lift and various vehicles unsupported for 10+ years, so if it's now mudjacked up, isn't it technically thucker than 3.5"?
@@khoatran9482 I don’t think so. The force is not necessarily downward compression. As the lift gets loaded up the uprights naturally want to bend inwards. It’s these bolts that pull the uprights straight. So it’s a pulling force, and I don’t know that the mudjacking actually bonds to the slab and therefore won’t actually add any additional pull resistance… if that makes sense?
I would jackhammer out the concrete under the lift (maybe 10' x 10'). Get a Harbor freight jackhammer and resell it after your done. Pour a new 6-8" steel reinforced slab in the hole. Reinstall lift. Seal water ingress. If you're really paranoid, drill some holes in the rest of the floor to check for voids.
Get a core drill and cut some inspection holes to get an idea of how extensive a problem it really is.
There is a chance the problem is not as extensive as it seems.
Maybe you can cut out the mounting areas and pour deep pilings to mount the lift and solve any other issues as they are identified.
Just my 2 cents.
If you could find a cheap piece of 1 and 1/2" inch steel plate as long as the lift is wide and wide as the hoist mounting surfaces, you could anchor that to the floor and attach the lift to the plate, but I doubt that you could find a piece of 1 and 1/2" steel for cheap enough (including transport to your shop) to make it cost effective. It would totally solve your hoist problem if you could though.
I would have someone come in and foam level it. If you really feel unsafe with the lift then get a set of quick jacks. The load will be spread out over more area.
I had the same problem in my railway shop…with floor heating. Drilled holes and used sandblasting equipment to blow fill and pack the void. Mud jack company wouldn’t come because of the floor heating
I'd propably just cut out the area, where the lift mounts, maybe like the long irons plus 30cm around it, dig those out deep, genuinely like over half a meter deep, and pour deep point foundations, like if you'd mount a jib crane.
To solve the erosion, I'd dig out around the shop, put in water barriers and drainage.
If I was feelin really fancy, I'd tear up the poured concrete and replace it with brick pavement, and while im at it, I'd replace the eroded dirt with coarse gravel. That'll allow water to flow through without eroding it.
You’d be surprised how cheap you can get a solid second hand lift from shops that are going out of business or changing locations etc.
I had a mechanic that bought a very solid lift for $600 about 15 years back (do whatever inflation calculations you wish)
I would see if you could pump something underneath it to at least stop the water ingress. Then if i had room id look at adding on to the shop, putting a new thick slab in.
Looks like that lift was already modified with 2x2 bars to spread out the weight forward and aft so guessing the installer new it was sketchy at best.
What would I do today , not look for info in the comments but get someone who knows what they are doing to look at it.
What would 25 year old me do ....... get some 8 ft long 3/8 thick 2x6 angle or square stock and weld the bajezuz out of it wont fall forward or back and make sure the tops of the hoist are held apart with some 2x6 1/8 wall as a spreader.
The 5000 ish LB lifting pile of obsolete you can use until you save up to do it right then.
Final thought, get it fixed or out before them kids are old enough to be around when its in use or wanting to use it themselves.
Peace
The 2x2 bars are factory according to the parts diagram. Had a foundation rehab company out today- I should be able to save the lift!
Wes just did something like this by pumping concrete below bhis slab. I'm still jealous
Before this it was the roof rotting out and the gutters getting replaced, before that the pipes froze and burst, before that my circuit breaker panel melted… still jealous?
@@thedoubtfultechnician8067 why yes I am. I have a crappy 2 car garage with quick jacks.
I was just trying to ease your jealousy :)
@@thedoubtfultechnician8067 it didn’t work nice try lol
You’re going to have to get in there to see how bad the damage is. And I mean, is it just that area or has it spread to other parts of the garage. That what would scare me.
The whole floor was flexing when he was jumping it all on there so I'm guessing it's pretty hallow.
The workshop is an addition, essentially a different foundation. The main part is built like a tank. If I go the mudjacking route, they use ground penetrating radar to find and eliminate the voids.
That was probably just the camera bouncing. It doesn’t flex- but you CAN hear it’s hollow.
Could you just pour a new slab on top of the old one?
I think that would collapse
I’m curious any updates on this?
Hopefully having it fixed end of July, will definitely post an update video!
hopefully only the garage and not your house. I'd make a new slap, and use the old lift for as long as it works
It’s detached, fortunately
any update dude?
Yup!
Workshop Update: I Saved My Foundation Using FOAM and GLUE
czcams.com/video/WUeooQoaOa0/video.html