How To Fix A Sunken Sidewalk With Spray Foam
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- เผยแพร่เมื่อ 19 พ.ค. 2024
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It might come as a surprise but you can actually use a standard can of Great Stuff spray foam to support a sidewalk that has settled over the years. This can be a quick fix if replacing this section of sidewalk with new concrete isn't in your plans/budget.
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Chapters
0:00 Intro
0:20 Drilling Holes For Spray Foam
1:21 Lifting The Sidewalk
3:14 Filling In Void With Spray Foam
4:38 Cleaning And Sealing Concrete Section
DISCLAIMER: This video and description contain affiliate links, which means that if you click on one of the product links, I’ll receive a small commission. - แนวปฏิบัติและการใช้ชีวิต
As a concrete and foundation inspector employed by a company specializing in poly foam lifting and leveling, I can attest that this method is highly effective. One crucial step not to overlook is the curing time. While commercial-grade poly can solidify in 15 minutes or less, as mentioned in the video, Great Stuff will require a longer curing period. Excellent video, my friend!
Don't the holes directly in the slab potentially cause it to crack?
Seems to me the best way would be to insert hoses under the slab and pump it in that way until level.
@@walkermom100no. A distribution of holes is needed to get good support underneath.
Well thought out and executed. You’ll probably get comments about easier and less costly ways but remember this you made a clear and clean video.
Thank you!
A clearly visible horrible way to accomplish this.
Today I, an unlicensed not contractor, is going to show you what they came up with in thier own head. Once again showing people how to do things wrong.
Are you seriously telling me you would pay someone to drill holes in your walkway and spray foam it? I would withhold payment and contact the city inspector if that was done professionally.
@@brandonhoffman4712This is what the contractor would do. It’s not just this guys idea. You would “call the inspector” lol. Admittedly the contractor would use a foam with a hardener that would likely last a while longer, but worst case this foam compresses in a decade or two slightly in which case you add a bit more foam. You really seem like the type who has never picked up much more than a screw driver.
We had a company come out and do the same thing, but if I was to do it again, I wouldn't let them drill the holes because we got a few cracks now between a couple of the holes. When I was a kid we'd use a breaker bar and just lift the sidewalk and put dirt under it and then put it back down. I think overall, that is the better option and no drilling holes in the cement and trying to match the color later
Thats definitely the best way when its rain and erosion likely moving the dirt over time. That foam can set uneven and definitely stress the block with other gravitational forces.
I laughed because that’s exactly what I would do if I found an uneven sidewalk slab in my yard. This video, although well done, reminds me that sometimes people make things too complicated…
@@overbuiltlimited Where I worked was a workshop and offices attached. The offices started to sink a lot. You feel yourself walking downhill. They drilled some test holes and found it was built over a dump site. There were all sorts of voids. So they raised it back up with concrete under pressure. I though that can't work, you've added even more weight. Sure enough, it raised it for a while then started sinking even quicker. People got sued and the whole place was relocated.
That is the best method, because with Winter frost water will freeze under that foam and may lift that area.
You actually had a company that did the same thing. That's interesting.
With all due respect to your ingenuity, which I applaud, I had this exact problem, but had a much easier - and cheaper - solution. I grabbed my neighbor, and together, we struggled up the broken off, but intact, 4'x2' slab until it was resting on its edge. I then shoveled the requisite amount of dirt onto the area, then struggled the slab back down to slightly above level, allowing for compacting of the new dirt. Less than an hour, no jacks, no support beams, no chains, no j-hooks, or drill needed, and didn't spend $16 on spray foam. That was over a year ago, and the slab has now settled to level.
same here. the only thing I caution is to never lift from a corner of the slab (did that on one of mine and broke it off). All the others I lifted from center edge and no issues at all.
And no holes in the slab to repair .
He’s the type of guy when u work on something together his way is the only way and his ears are blocked
I was just going to say what you said.
step 1 lift slab. step 2 insert dirt. step 3 put slab back where it came from. step 4 the end.
Your solution requires finding and begging a friendly neighbour, his doesn't.
Thanks for simple , to the point video. You do not talk about your puppies , neighbors or other unnecessary items.
Right!
Lol
But at least you took the time to discuss them…perspective is everything.
😂right!
He's got puppies?
I like that you showed your lifting rig before you made it. It's nice to see what's being made before you make it rather than spending half the demonstration wandering what's being demonstrated.
Other youtubers should use this format :)
Must be an engineer. I never seen anybody make such a complicated project of a simple repair. But I did watch for a minute like a dumbass so mission accomplished.
The most valuable part of this demonstration to me was the use of C clamps, jacks and timbers. Raising the slab with such control allows the use of a variety of fill-in support methods.
The tip about drilling concrete with a rotary hammer is valuable too; I learned that after struggling with a simple hammer drill.
Thats why you hire reputable professionals. Lifting and trying to back fill at edges won't work. Slab will crack due to voids in a large area. Unreinforced concrete cracks wire mesh doesn't do the job. It bends with the slab over time.
It's literally 3 bags of concrete. Remove and replace is your best option
@@travishanks7295 LOL exactly
Very smart! But if crappy or suspect walkway, suggest scrap of wood (at least 3/4" ply) under each bottle-jack to distribute load… avoid cracking and another project 😀
Yeah. Spreading the load under the jack is essential especially over an unreinforced concrete base. I foolishly assumed a 125mm fully cured slab edge would be OK to use as a base to jack from. Maybe my 20 tonne capacity jack was a bit much but the instant I had the satisfaction of the sound of my lifted slab jump free and move up as I intended, I had the disappointment of seeing the cracks as my relatively new slab cracked right beside my jack. I had watched professional 'mud jackers' on YT and arrogantly assumed it was all just as easy as they made it look. The sheer stress I induced under the jack must have been greater than the lifting force applied to the displaced slab initial resistance.
I've never had an issue with concrete asphalt yes. But this is rated at 3500 lbs per sq in. And that slab he is lifting is only 1/4 yard or 500 lbs max (2000=80 sqft @4"). The 4 lift areas dived by the 4x4" Jacks makes that an over kill.
You did an excellent job lifting it and setting everything back level. When I read the thumbnail I was very sceptical and my first thoughts was that foam will not lift that slab. But once dried it most certainly will hold the slab up.
Thanks for putting this out here! I was picking mine up and releveling the dirt, but after a year or so they settled again unlevel! This really helps!
if they continued to settle again after leveling them, then this might be an indication of a continuous problem going on under your slab, such as erosion from rain water drainage or a leaking sprinkler pipe and even tree roots that are causing shifting in the soil under your slab(s).
I am a concrete contractor. This guy did well. Not sure how long it'll hold, but he saved himself some money. Wire mesh, used initially, would stop this heaving, but many don't want wire in their sidewalks, or they don't want to pay for it.
I would never offer that service.
My repor with homeowners is critical to me. I don't do half way fixes that destroy a products structural integrity with holes.
Someone else can have that job. Maybe a youtuber could swing by and do it...
I've had the opportunity to spray foam many fixes over my years in the trades, I've jumped @ none of them. The main thing I use it for is its to seal the bottom of drywall gaps to the floor when I do a self leveling underlayment.
Great video. I was really excited when the slab got caught on the rock building pressure and then releasing with a sudden movement. I could not help but think that this was a great analogy of how some earthquakes happen.
I have done this and it works very well, although I didn't use the jacks, I simply raised the sidewalk slabs with the Great Stuff foam. It will expand and raise the slab on its own, but be careful not to inject too much, because then it could end up being too high.
The only thing I would recommend is to save the concrete dust from drilling the holes. Then you can put that on top of the caulk that you put in the holes so it blends perfectly with the existing sidewalk and the holes won't show.
That’s why he raised it first so the excess woukd or could glow out holes
I like your concrete dust idea, but I like his raising and setting better. It has more precise control of the slab's height and level with escape channels for the Great Stuff Big Gap on the sides. You're right when you say it could expand too much.
" I simply raised the sidewalk slabs with the Great Stuff foam" ?????
@@rufflesinc the contractor's way is to foam jack a slab, but with that lil fella the method shown is most effective.
Thank you I was going to ask about that because I have a part I can’t raise but I know is sinking. It’s a slab.
Anyone concerned the foam might get compressed over time. There is another product made by Loctite called Tite foam. It is advertised as being 4 times as dense as other expanding foams. It has been a long time since I purchased it but it should be comparably priced as other foams and available at many of the same stores.
Not worried. Certain.Urethane spray foam is not weather proof/ It will degrade overtime and if an animal finds it it becomes an easy place to dig. This is a 10 year fix at the outside.
compression is not really an issue because even a several hundred pound slab is only a few pounds per square inch. IOW, hardly anything in the big picture.
Great video. We had enough issues that we had sections aligned by a company that pretty much did the same thing. Although I wonder if the foam was the same or less susceptible to long term degradation.
You also covered a key thing about dealing the joints, prime point of water entry under the slabs. I used backer rod with Seka sealant, both regular and self leveling, for this. I also lightly spread sand into the sealant while wet, then brushed excess away after fully cured. Makes for a nice appearance.
They actually make a load-bearing foam for doing this I don't know why people keep using the air blocking foam
@@thecloneguyz I will jack the slab and I have an Airplaco hg-5 grout pump that I will pump mortar under the slab with. Did it in my backyard 10 years ago and it is still great.
Great video for small projects. Nice process for curing the problem. The last project my company did before retiring was to raise pavement slabs on US 75. Of course we had industrial grade pumps and the foam pressure lifted the pavement. Your methods work really well for smaller projects like walks and smaller patios! (And the joint sealant video is also really good.)
All the hardware and materials needed, just remove slab make a new one
I did something like this about 5 years ago. I had to raise a pad in front of a two step porch/entry. I did all I could to raise it, tracktor & loader, crowbars (big ones), and more. Got it to about right, close as I could get it and stuff all I could under it, including several cans of foam.
I also repaired two broken step corners with a concrete mix and forms. It was pretty good, but didn't match. No one complained but I wanted more.
So I got some of that polymer resurfacer and did it all plus the 40 ft of sidewalk.
All looks great now. And I made the polymer a bit thicker to get the rest of the leveling I couldn't get before. This was a 60 year old sidewalk and step.
I have just gotten one step closer to being the smartest man on Earth
Fantastic idea. I watch this guy all the time and haven’t been let down yet.
This is a great fix. I know commercial guys do the same thing,but charge a high price. This is fantastic and easy. Thanks!
I have no issues like this to repair, however I did want to leave a comment because you did a great job of explaining things in a direct manner. Much appreciated!!
I have issues. So did someone else with the cracks they received in thier concrete going from hole to hole...
This isn't a fix. Your watching the slowest demolition ever...
I mean seriously, spray foaming soil a subsiding property with home insulation gap filler.
Does he fix his house leaks with duct tape & bubblegum?
Stop watching MacGyver!
Great demonstration of how to resolve this issue - i know alot of residents have these trip hazards. A final addition to your presentation, is to work out the math on a white board, to show the cost of "remove & replace" verses "lift & support". It was great to watch this. Greg (garden grove, CA)
This is a horrible MacGyver episode. Where MacGyver breaks free from his trip hazard with a drill, insulation gap filler, and 2 shoe laces (still laced in shoes).
Today folks, I an unlicensed, not contractor. Is going to show you how to destroy your homes structural integrity.
I learned more from Tim the tool man... Like how important a good neigbor is!
This is gold, My company does poly level and can lift and support sunken in walkways, driveways, roads ect but it is costly.
I’ve been wanting to pay someone to level out my sidewalk out near the street. Had the driveway and patio done a few years ago. Also thought about having the city come out to grind down the bumps. Your video has given me the confidence to do it myself. Wish me luck.
Love how you make it so Joe homeowner can do it. Thanks for sharing
Brilliant, one suggestion I use often is save the concrete dust and dust the top of your plugs with the dust. Perfect match to the surface in about a month or two!
Here's a brilliant solution. Just lift the concrete out of the way by standing it on edge. Get a little stone dust or good packing sand. Then level the area to the appropriate hight and lay the slab back down. It's pretty simple. Tools required; lever, fulcrum, sand, level and tamper.
@@shealdedmon7027 At 50 pounds per square foot of 4" slab, that area is going to be heavy with a capital H. Not saying it can't be done as you describe, but that section is probably approaching 500+ pounds.
@@shealdedmon7027 the solid layer of foam will be sufficient to keep the concrete from settling. Foam has been used under concrete for decades now, and works just fine. Most commercial freezers are insulated from below with foam under the concrete floor, dating back to the 60's.
@@5thGenNativeTexan No problem with the “power” of leverage and having a good size breaker bar or Johnson bar.
I love how you quickly found out your cordless drill wasn’t cutting it. I had the same revelation a couple nights ago trying to reattach loose furring strips behind drywall in my basement. Started off with masonry drill bits and my Milwaukee hammer drill, 45 minutes 2 holes and a dull drill bit later I got a ramset tool and got 10 more done in 15 minutes
I've seen your videos before , i enjoy the clarity of the and the way your explain in details pretty much what you're a doing ,thanks for sharing and keep up the good work.
Cool fix and this is why you should use rebar when pouring concrete in the first place
Great job lifting it and making the video. For the gap, I prefer Sika Flex self-leveling sealant.
I did this same thing only I drilled a couple extra holes in the slb and screwed in a long cement lag screws (instead of the C-clamp method) to attach 2 pieces of chain to then hooked those to my board in which I used a floor jack to raise the end of the cement slab. Great vid and thanks!
Ingenious one-man operation! Thanks for sharing!
Great video. I would even consider letting the closed cell foam do the work for you. In a rennovation, I added a new tub. The overall contractor doing parts I was not wanted to spray foam under and around the tub instead of my concrete base. Thinking that a metric ton of water is heavy, I said okay, but you own the mistake if there is one. We came back the next day to see how all the work was and the tub was lifted about 1.5" upward breaking the seal to the marble slab it sat on. If we go better at this, we could measure out and do this with spray foam and bypass the manual lifting. I do appreciate the control your way has though.
Nice workflow. I think you could do the same thing with shims from the sides with a tile that size.
Great job, Lots of pride in his work and home.
I just did this today using your suggestions and it worked perfectly. Thanks
Excellent tutorial - you have shown a really reasonable method for fixing a sunken sidewalk slab. Thank you.
ggs113
ggs113
1 second ago
I second the comment, Sharon.
Put G clamps in a poly back or cover with wide sellotape. It makes the clean up of tools a lot easier.
Good project and very clear for beginners. We'll done.
Great idea using bottle jacks!! I've been trying to figure out a way to lift slab aside from renting a skid steer this is awesome.
Big respect! I learn how to raise the concrete you made it look simple, if I had known how to, I actually demo and built new pad
Interesting idea but much simpler; I lifted each side with a heavy 1” x 6’ breaker bar from HDepot, temporarily stuck a few large rocks to hold it up, removed the bar and dug under with a hand shovel a bit then mixed concrete and shoved it under wherever I could. Next day took out my temp rocks and dressed the dirt edge back up.
Can we see the video?
Thanks for the video. I tried lifting a sidewalk slab with a 6 foot prybar but wouldnt budge.
Good idea to use a jack.
I think others may be right that it could be a lot less complicated BUT I'll try another way first and post a video before I either suggest an alternative or eat my hat.
Thanks again.
I paid a concrete leveling company to do this in 15 minutes for $300, but they didn't use spray foam. After they left, I poured dry sand all around the sidewalk section to fill the gaps and packed the soil in, so it can't happen again. I am impressed you were able to do it yourself.
Great video, I have a small sidewalk leading to my outbuilding and it's sunk near the building. I'll be doing this next spring
I did mine differently. I clamped angle iron on the adjacent slab and left the overhang over the slab that I raised. Used this a a stop so it can only be raised to the same level. I used an air hose and a piece of pvc to blow out a few channels under the slab. Simply added foam in the void. It lifted the slab until it hit the angle iron and then the excess simply flowed out the sides. No holes. No jacks.
I have a customer who was wanting to do this exact same thing. But I told him that wasn't in my wheelhouse and wouldn'tknowwhere to start. . Now I'm going to tell him I can help him get that taken care. Thanks.
Great video! Nice to know that anyone can do this by themself without having to pay and arm and a leg to a contractor.
I did this with my sidewalk out front to avoid the city charging me $625 to replace 2 5x5 slabs. Worked perfectly with the c clamp method. The 2nd block had some obstruction so I could not dig on each side. I had to lift by installing 2 5/16 tapcon bolts. Because there was no outlet for the excess foam I ended up overlifting by 1/2 inch so I had to lift the adjacent slab. I used the drill dust and some fine gravel over the self leveling sealant to blend into the existing sidewalk. Looks great. Also found out the foam doesn't yield after it sets up(less than 1 hour). No need to leave everything up overnight.
This is a miracle video. I have the same situation and was worried about someone visiting, tripping, & sueing. Now I have the solution on how to solve the problem. Thanks for sharing!
Very interesting, but I have seem multiple occasions where Great Stuff deteriorated over time, just turning to dust.
Also, it was never meant to be load bearing.
I'd be very interested in seeing this slab in a year or so to see if this works.
Our HOA contracted a company years ago to repair the neighborhood sidewalks and they used grout pumps to both raise and support sinking slabs. It's still working after maybe 15 years.
A manual grout pump can be rented for about $75 per day in my area.
Polyurethane foam does not do well if exposed to UV. So it needs to be painted if used outside where light can hit it. Hopefully he did a good job covering up the foam beneath his sidewalk. I have brick steps rising about 3 feet from the garage floor to the kitchen door. One side of the steps is against concrete block foundation, the other side is a crawlspace. When I bought the house there was a hole about 3 inches across through the block next to the steps. I filled it in 30 years ago with foam, until I could get around to using mortar. I was worried about vermin getting under the house. The foam is still there and holding up well.
It won't deteriorate if protected from sun and air.
Seems like a short term fix with lots of equipment to me. Just have some friends, lift this thing off, and add gravel and done...
Yes true 👍 🙌 👏
It's not really bearing load. It's just bearing a few vertical inches of concrete weight for every square inch of Great Stuff. If it were a slab foundation holding up a structure, your point about load-bearing would be well taken.
Thanks. I literally just lifted a section of my driveway with a hydraulic jack and tractor jack then concreted under it. I've still got a lot more to do and now that the driveway is supported with concrete, I wanted something else to fill in the gaps.
Trevor, good point! I would haveJust lifted it up and put a couple of blocks underneath to level it and then, add a length of tubing to the can of foam and insert it into the middle!
Great video. Here's a idea: instead of drilling through the concrete, as a means of getting the foam pushed into the center, how about inserting tubing under the slab after is it lifted? use these as conduits to spread the foam.
That's a smart idea. I think the process he showed would more often be used for a larger piece or for something where you couldn't get access through the sides.
I don't think it would be bad if that bit of path way is in reasonable condition and the holes you drill are quite a distance away from the edges of the pathway
My thought exactly. I'd rather dig 6 inches around the edges than drill holes. Then just slide A few feet of vacuum hose from the auto parts store into the newly created gap, spray, move around if needed, until the gap is full of foam. I'd still like to give credit to this video for finding an easy way to mimic the professionals.
Also, I'd be interested to hear if any of the concerns of this type of foam expanding too much(raising the repair too high) have happened. If so, then it might be wise to use "door and window" spray foam that only fills the gaps but doesn't add extra pressure. Apparently using regular spray foam around doors or windows can expand too much and interfere with opening/closing--the same principle should apply here.
so silly, why do you think the pro's drill? 6 inches in only? your slab will crack in the center eventually ecspecially on a wider bigger piece. Ya''ll in for a world of hurt.. but maybe some I've got a better idea dude will get lucky@@danthomas7862
Perhaps use the foam for lift by shooting some under the center, and packing earth on either side? Gently tamp periodically to try to distribute the foam a bit and keep it from raising up too much?
I worry that it'd continue to expand
Just Grab your angle grinder with a masonry disc and grind the corner of the protruding block off to a comfortable angle.
Great vid Stay Happy and Healthy
I was wondering why they didn't do that. You can use the grinder and also one thing that repairs concrete well, is more concrete. I used to drive Illinois and other north-central U.S. states and they often saved money by using concrete slabs on their highways.
The better maintained ones would have a crew close a lane from time to time, and they would have a couple guys separated, using huge angle grinders and face shields to smooth out the transitions. Using a toxic plastic foam that is not permeable and not nearly as sturdy as concrete seems a real short-sighted fix.
I needed an idea on how to lift my slabs! Thanks for the help.
Great video, going to fix my walkway with this method soon
Amazing amount of engineering. I have lifted pieces of concrete as well.
Generally for a sidewalk piece - this size - a large crowbar or 2x4 used as one will lift the slab. Spray foam definitely can lift the slab as well as hold it.
What i do - You can lay a couple 2x4s that are min 2’ long each - each side on top of the side walk pieces so their spanning the other unheaved sidewalk. Get your large clamp or even a bar clamp - squeeze the concrete two the 2x4 lifting the slab with a crowbar if even needed. Throw dirt or your foam under there.
The pieces are heavy but way more movable then you would first think. Generally if piece is in good condition it goes quick. If cracked you may have a bigger project.
The best foundation to put under the lifted concrete is usually add some sand. I pile it into the gap under the lifted slab. You can usually soft the sand in well by using a garden hose and just blast sand from the side - swishing the sand mud under the slab until full.
Great process for doing this - I have something similar with my sidewalk and this might be the ticket to fix it w/o hiring someone :)
Good idea. A new slab would look obvious. The natural look makes everything look like there never was a problem in the beginning.
.
Being as the steps were attached to the slab that was lifted I get why you did it the way you did, it needed to be exact lifts with minimal pressure applied. All of these people commenting about pry bars and such should do some FAFO research. Very nicely executed and with minimal breakage to back or slab.
Absolutely outstanding video. Wow. You explained it SO well that I wouldn't be afraid to try it, and I'm anything but handy. Thank you!!!!!
Spectacular solution! Well done. Lot of homes could use this treatment.. but, like shirt says: requires "sweat equity"
I have the exact same issue. Brilliant!! Thank you!!
Super video. Lifting first and then supporting is the ticket. Thanks,
I had a professional company try foam under my brick paver front porch after it started to sink in the middle. After 120 lbs of foam, the sides leveled off but in the front near the steps, it was rising. They refunded my money (very expensive) & I had my contractor rip out the pavers and pour a stamped concrete floor with rebar. Turned out great.
@@Etron49 That's what I thought about halfway through the video.
awesome vid, no excess bs talking, just exactly what was being done
A+++ video and highly applicable to a LOT of homeowners!!!
Foam lifting is for large slabs. It won't help much if you have other problems such as an ant nest under the slab. Better would be to just lift the small slab, deal with any problems that would cause the issue to reoccur, add the appropriate fill material, and lay the slab back down. I've also seen places where the issue isn't settling, but uplift. In those cases, you have to remove tree roots under the lifted section.
That's amazing, you should make a video
COOL STORY BRO
Ants would not stop foam but would be a dead ant nest
Just perfect. I probably add 4 large rocks wedged at each corner. Big difference and very clean look
I agree. The foam may be sturdy, but it has give and will move more than a solid object.
I did a driveway slab this way and I ended up putting foam in the middle but my son and I dug out around the perimeter and added blocks under all the edges after we put down gravel and compacted. Much more work but I feel better that it will last a long time. That was about a year ago and it has not moved one bit. Yet.
best home repair vid I have seen here, keep it up, and I am a 50 years do my own repair renaissance man…lol
This seems like a great method!
Previously, I’ve worked on a slab jacking crew. We would do the same thing. We however wouldn’t use “foam” but rather a mixture of Portland cement (to harden), ag lime (as filler), and bentonite (to aid in flow- not sure if it has a purpose out side of that). This mixture was touted as “safe for the environment”.
The 2 problems with slab jacking are:
1) cracks happen sometimes
2) typically can’t get things back to “original” but close.
With smaller pads, lifting them up with a couple bars and packing dirt under is probably the best bet.
Be mindful of erosion and you’ll save yourself a lot of money
Bentonite expands as part of the curing process. I'll have to remember to use some of it next time I do this.
@@CrabgrassFarmer yes I wonder if it retaining water would allow for the Portland to not cure correctly. It seemed like it worked when we did it.
@@SoTaSpEaK There is enough water in the soil to make the cement cure with time.
The bentonite and lime will also reduce the strength of the mix so that it can move a little bit and reduce the chance of the slab cracking.
@@johnclements6614 I see. Thanks for clarifying that.
Great DIY approach to fix this problem, I would think that self level floor cement would be better to funnel in the holes as the foam would compress over time and the pad would sink down
Exactly my thought. This would end up compressing at some point. Cement would be the way to go, I think.
Yep, I washed sand into a cavity under the corner of a driveway slab until it was no longer hollow. It worked great. I've done it with large cracks before sealing them too. Play sand works great and flows with water quite well.
I've always tipped the slab on edge, corrected and compacted the bed, and laid it back down again. You save a lot of time excavating, but it can be fiddly getting it leveled out. Still, you're under no time constraints, so you can just tip it back up, add or remove material, and lay it back in. If you have access to fill material, it's a zero-dollar job.
Thank you very much! This really helps us with the possibility of what we can do for ourselves and save thousands of dollars!
I have to say that was very cool to watch, learn and understand.
Great Video!
pro tip with these cans ... use needle nose pliers to grip the base of the dispenser 'nub' at the top of the can while you are screwing on the dispenser tube ... this will allow you to create a tight enough seal that foam will not creep into that seal ... also, you can use the cans a second time but to do so, it's best to clean out the plastic tube (assuming you only have the one) before the foam cures ... a long metal wire and/or an air compressor come in handy for this (*only after tube is removed from the can*) ... clean the semi-cured foam out of the nub *gently* as to not damage the nub and the seal inside that is holding back the compressed gas ... wear safety glasses for this ... *even with care, sometimes the cans are still one-use no matter how well you clean them
I clean the nub out with brake cleaner afterwards and can usually reuse partially used cans no problem.
Glad to see that someone is fixing tripping hazards. I tripped on a sidewalk like this about 12 years ago while working for the census and doing work at an apartment complex. Since then I have had knee and shoulder arthroscopy on my right side and I now need a knee arthroscopy on my left knee and I have had lumbar surgery. I ache all over in my neck back hips knees and legs. The sidewalk was raised because of a gutter coming off the building that made rain run under the sidewalk and bucked it up …. Miserable 😩
That sucks. Just shows how what seems like a minor problem can cause big pain/injury later.
I have this on my drive way but this I need to call a Pro to fix it due to the size of the project. I do not think a couple 4x4 are going to do it.
All that because you tripped? I've been in car crashes that didn't hurt for 12 years.
@@OlRubberNuts mr know it all … I also tripped and fell in an Albertsons parking lot in 2008… when I was 60 then again in 2010 at 62 so I was older and I took two very bad falls. If I had been younger I probably could have recuperated better but these two have done me in.
Excellent strategy and presentation. You do very nice work. A section of my concrete driveway subsided and cracked so I went looking for companies who do mud jacking. Couldn't find anyone local but did find a service that uses foam to raise slabs. They quoted me about $1000. I said "screw that" and went and bought a masonry product made specifically for repairing concrete walks. I built up the sunken area to be level and it's held up remarkably. Also, the materials were less then $50.
I have a garage with 6x6 slabs that make the floor. each slab has sunk in different directions. After watching you do this I think I could take a laser and mark where the top of slabs need to be and hoist them into position. I would pump grout under the slab until it is completely full and give it a few days to cure before releasing the tension off the hoist. I have been looking for a way to do this without demoing the floor and poring all new. After watching your video I clearly see the way to do it. Thanks
How long does this repair last before the foam degrades?
From an engineering standpoint, this is an awesome video but the practical part of me wants you to pour a new pad! This is a great way to solve the problem without having the mis-match issue though so I see the value.
Same here. I feel like it would be less work to bust out that slab an pour a new one.
Pouring a new slab? You'd never get the texture to match...
Also magnitudes more expensive and more work to replace the slab. He has $16 into the foam. If he had to buy the lumber and chains, maybe another $50, but they'll be useful for future projects too.
@@come_on_now Texture is usually created with a push broom. Not hard at all to match.
@@timfischer I disagree. It's $5 at my hardware store for an 80 pound bag of Sakrete for pouring slabs. You might need two or three. A single bottle jack (you need 4) is $25. A single large open mouth C- clamp is $15, and that's all before the chain, hardware or timbers.
Excellent video! Straight and to the point. Good job too!
Wow! Amazing, impressive, and best of all this actually works!
Did anyone else think it was just going to take the spray foam to accomplish this? Asking for a friend.
I’m too committed now. Time for some bottle jacks and posts
Yes
I don't have a sidewalk to fix, but you just gave me the perfect method to lift a small shed to put in a new crusher run pad and new floor beams! I knew bottle jacks were part of the equation, but fixing 4X4's to the shed and then lifting the 4X4 with chains might be the ticket. I'll run some calculations to make sure I'm not doing something stupid, though. Thanks - love the channel!
If you have not already done it you could consider strand jacks. They have a hole up through the jack through which you can pass a bar. Pass a bar through your 4x4 (or pair of 4x2) then through another 4x4 at right angles that is supported off the ground. Place jack over bar and secure then jack. Safer than bottle jacks that could tip side ways with you working under shed to prop it to do works.
@@johnclements6614 Haven't done it yet, so your suggestion both appreciated and timely! I'd never heard of strand jacks before, so I'm doing some more googling. What I've found so far looks like the cost would be higher than scrapping the old shed and putting in a new one. Any sources you might be able to recommend?
@@spud13x13 I used a strand jack about twenty years ago for testing bolts that had been epoxied into the side of a bridge. I am in the UK and have not been involved in hiring plant since then. I can not find anything locally to my self with a quick google other than a Chinese site selling small strand jacks for about £400. At that price new I would assume! (big assumption) that be able to hire a couple small jacks, hoses and pump (plus oil etc) for $100 for the weekend if you collected and returned them. I think it would be a case of finding plant hire companies near you that hire jacks then phoning them.
The thing about the bottle jacks is you will have to figure out a safe way of doing the work if they tip side ways.
I don't know how small your shed is but have you considered moving it. I moved a shed once by taking up the floor, putting some runners under it and levering it along whilst stood inside. Obviously puts stress on all the joints but the shed lasted another ten years till I built a bigger shed.
You're the man! Thanks for the video. You make it look so easy. That was a soup to nuts demo!
Wow. That's a professional job using bottle jacks.
Before setting it back down stick the long bit back in each hole all the way to see if it comes out gooey. That greatstuff can have trouble curing inside the center of a the "glob".
Pretty cool, nice job!
Excellent video. Great photography and perfectly explained Thank you
Fantastic! Some businesses want thousands of dollars for the fix! Thank you!
I love what you did and I could easily see myself doing that just for the experience and the ingenuity involved. That said it seems to me unless you wanted to match exactly the existing concrete when you take into consideration the chains the four by fours the bottle jacks all the little miscellaneous hardware and the fact that the concrete may crack during the process it may have been better just to pour a new section of sidewalk
I like your technic for lifting the slab. I personally would rather lift a few more inches so I can throw some sand under the slab. Might take a couple tries to get the right height, but better than drilling holes.
Excellent technique which I'm definitely going to try.
Excellent, as always, I just watched your tutorial on how to install another outlet where you removed the wall base..nice one!
Thanks for the support 🙌
Question, if you already lifted up the slab, lift it higher and put more rock and sand underneath?
1) did you fix the drainage problem that caused it to sink in the first place? If not, it will continue to sink.
2) the foam will compress over time, it's not a structural product. I've tried similar things with a retaining wall and straightening a mailbox on a pylon underground and both failed due to compression of the foam after a couple years.
Makes sense. Surprised he didn't insert some bricks or inject some concrete in the sides to guarantee it will never sink.
I would say the foam is a structural product. The compressive strength of the foam will support the concrete. Perhaps the failures you saw were because the compressive strength was exceeded.
Crazy amounts of different spray foams. Pop this small section out and pour new 3’x3’ pad. Cheaper and would last longer. Would drill 3/8 rebar into step and next sidewalk to ensure stability. Would not be surprised a drain spout is near.
1) You are assuming it was a drainage problem. It may just have been un-compacted dirt used during construction.
2) Some foam is a structural product. It is used professionally to raise driveway slabs. It is used to set posts.
@@onjofilms 1) This is not a new walkway and even if it was, if it was only a matter of un-compacted dirt then the adjacent slab would sink too, unless there is a specific extra weight placed on it, for example this happens on driveways where a vehicle is parked.
after i calk i put some play sand on the calk nice small touch . thanks for the vid i need to do this
I didn’t know that thing could hold heavy weight, wow, loved the video.
In my opinion and experience with foam is it is porous and water will seep in eventually causing it to rot and detartrate and sag again. I think for a more permanent solution would be to dig out under the slab partially and place some border boards and pour some cement with gravel under the slab to hold the slab indefinitely. No holes drilled or seem leaking problems. If the slab isn't too big, a large pry-bar or crowbar can easily lift the slab to position.
I can confirm the canned foams get water logged, can't speak to the damage it does to the foam, this video just feels like someone saw one of those professional services where they inject a foam using similar methods (but a different foam) and said "I can do that for cheaper" as there is actually a foam developed for this purpose.
Clamp a timber on the top and as you lift the slabs, clamp it tight to get the top flat, clean the joints out,, then you can either use the foam, or pour free flowing grout to the underside of the slab - shutter the sides to prevent leakage.
Remember to heavily grease the end of the clamps that end up under the slab (best to wrap them in plastic too) and yank then out as the fill sets)
Grout seems like a better long-term solution to me. I would worry about the foam degrading or the air pockets collapsing.
@@N20Joe I'd not use foam unless I cemented up the sides.
I've seen instances where unexplained floor slab subsidence became very easy to explain after foam was used.
There was a trail of foam granules along the narrow gap behind the building that the resident rats had removed to get back inside
Of course they now had a super insulated home.
The clue is in the name of the product "gap filling foam" it's isn't structural, it might well work, but it's not a true ling term solution, the foam will break down over time, it isn't designed to be saturated and encountered temperature extremes, boats fail because the exact same stuff pumped between the skins form the structure and when wet it crumbles