This is a great solution if you don't mind drilling through the slab. This will leave noticeable drill holes on the surface of the slab. If you don't want those and you have access to one of the sides of the slab, another option is to clear out the dirt along the side and then dig under the slab a foot or so. Then you can slide your jack under the slab directly. Use some rock shims to place the slab at the level you want and then you can use your spray foam to fill in the rest of the voids.
Thanks for a great informative video. It's perfect for a DIY'er that knows a hired out job like this would be 10X or more the money you spent. Sure, there are comments here that are "negative" in parts of your process but any DIY'er gets the basic concept of what and why you're doing it. You explained it well. Good Job!
Sidewalks are 31/2 to 4 inches thick, driveways should be at least 6 inches. Make sure your bit will be long enough. You can use backer rod or even sand to fill the gaps. Also if you sprinkle a little on the filler after about 10 minutes it makes it blend in better with the old concrete and also helps stop grass, leaves, or twigs from sticking to it as it dries.
Sweep the concrete dust after drilling the holes into a dustpan. Then lightly dust the self leveling sealer with the "dust" so the repair blends in with the original concrete
@@jcx5659 my father had our house built in 1965. He was friends with contractors that built floors in the automotive assembly plants. They had extra concrete and they poured our driveway. 8 to 12 in thick because they did commercial work. It was quite a surprise to the gas company when they want to do with the gas line that was under the driveway. They had to bring in an excavator with a jackhammer and because I hand operated Jackhammer wouldn't penetrate the concrete. We had commercial HVAC as well. There are always exceptions to the norm
I love seeing dyi! I do this professionally with poly foam injection. For your holes it's also easy to just use Portland cement and sand and water to patch your holes and have it match closer. Also to seal cracks just get some play sand from your local hardware store to mostly fill the cracks then use your self leveling caulking. Great video! Josh-Stable Concrete Lifting.
I like your video. Simple & straight forward. This gave me some ideas on how to raise up my garage floor. I like the way you drilled & used anchors to help in lifting the concrete prior to filling the gap with foam. I may use a different type of foam but all in all a good idea. Thanks for posting. Nice job man!
BEST technique I've seen thus far! I would have never thought about using the concrete bolt as an anchor point. The other techniques wouldn't work for me on my old sunken in porch. It's cracked in several places. I might give this a try!
I just did this fix using your video as a guide. Worked like a charm! put the spray foam into the cavity under the slab and will let it set up overnight before taking the jig off. thx for this GREAT video!
Thanks man, this worked. I did definitely overfill shit, apparently acetone can help in that situation, it'll eat up the foam before it cures. I put my car on the corner of the slab that's high and jacked up the back end, which has held it from expanding too much. I think the actual cost would have been like $400+ from any shop, but materials for this was like $50. My only tip is to buy a square washer, they have them at home depot, they're very thick, no need for a secondary board to strengthen things. They're like $5, apparently they're called bearing plates. Additionally, if you have a gap you can wedge in a prybar, I used that + the jack, I'd get the jack tight, prybar it up a little, tighten jack, so on and so forth. Thanks again! Gl everyone. Edit - For those who come later. I apparently leveled the wrong thing, so I had to level 3 sidewalk squares. I learned a few things, which are very useful. Cut a 2x4 to 2ft long, Drill a hole in the mid for a concrete anchor (3/8ths worked, 5in length), hammer in anchor, put board on anchor, put bearing plate on, tighten nut. That's really all there is to it, just tightening the nut is enough to lift the concrete, no jack necessary, and much less work than building a thing. If necessary, do one more to give yourself extra strength, you could even do 3 if you had to, but I'd assume your slab is overpoured and connected to nearby concrete if ,2 isn't moving it, so if you have a sawzall or something like that, you can go around the edges and make sure it isn't connected to other concrete. If it is connected to nearby concrete, we used a SDS hammer drill, and sawzall with a thick carbide blade (12in 1/4in SDS bit) . I believe there may be circular saw blades, or angle grinders that may do a superior job for cutting through the concrete, I'm no mason. To be clear, you just tighten the nut to lift the concrete, if you're doing 2 then alternate, tighten one then the other because when one gets tighter the other should get looser. Also expect the concrete to lift up a little bit more than you have it set to once the foam fully expands (probably 1/4-1/2in if you fill it up to the point where it comes out the sides before your cans empty, if you did more, it could be sizable.). Make a mark on the cement so you know if it's lifting, it's really hard to tell. You don't need to cut the anchor, if you have a hammer drill just push it down, or a hammer and a punch (assuming no are running inches below your cement). Lastly, if you're dealing with overpoured cement, we used the SDS drill and a 12in drill bit to make the connected area into swiss cheese, I would make consecutive holes, then come from the sides making more holes at like a 45+° angle, both sides help. After that a thick carbide sawzall blade can cut through, but as said other options may make more sense.
Wish I saw this a hour ago, I dug under my slab in two spots and used to jacks to raise it up, but I have a big patio that has pillars that hold some of the roof up over the patio but will be using this idea to do the rest of the patio
Tip… Save as much as you can of the drilling overburden. Use this to disguise the filler at the top of the holes. Also, measure the holes evenly. It will look more intentional than a later repair.
Just my $ 0.02 - don't bother with a wire brush around the holes, that just makes them more noticeable. Just brush the inside of the holes before you seal them up. For sealing the crack, use 'Crackstix ' for cement (availing for asphalt too). These are hot fill rods and melt with a torch. It's superior to sealant which will shrink and open up again. Also use your sawzall to remove the foam inside of a putty knife.
I've done this a couple times. I thought I invented it. I dug out some of the dirt or gravel on the outside of the concrete pad and used a HI-LIFT jack to get under the concrete pad and lift it up. You might have to put a 1' x 1' +/- piece of plywood under the bottom of the jack to keep it from pushing into the ground. Worked great!
I like this process better for sunken sidewalk slabs better than the process of jacking using the large, 8" "C-clamps" as it does not require as much digging nor expense to purchase those clamps plus chain & other hardware. Both processes require drilling holes to then fill with expanding foam for the gap created under the slab.
I've been looking at different types of foam. I found there is Open Cell and Closed Cell foam. It's hard to find the difference, it isn't really listed on the product. I have seen a few videos using Secure Set foam. Froth-Pak IS available near me but I can't tell if it's closed cell like Secure Set. Thanks for your video. I need to lift a section of driveway.
I get the concept but unless there’s rebar of some sort then more often than not that anchor will break off a chunk as for digging underneath and jacking it up you’ll need a hardy portion of plywood to help ease it up At the end of the day you do what you can with what you have. I also give props to the video for simply trying to bring a solution to the table
@@jackofalltrades7822 save the dust from drilling, then throw it back on top of the sealer. itll have the same color too. works great for brick as well
How about using small amounts of hand mixed concrete and cushed rock to cover the holes better and and use a brush to copy the same lines used when the original brushed concrete was poured.
what i normally do is keep the dust from drilling the holes then caulk or cement the holes then put the drill dust back on top. It usually matches the concrete
How do you keep the foam from expanding so much it lifts the concrete too high? Guess you have to kind of estimate it as it expands to 3 x and I've seen other videos where it actually lifted the concrete.
It kind of settles itself. I sprayed in enough so that it was just a little higher than needed and it settled. The expanding is not that strong to provide a ton of lift. That’s why you have to Jack it up. Thanks for watching.
thank you for the effort of making that video, very helpful. One question to everyone, how long is that gap filler supposed to last in the wild, ie outdoors under small slab in texas clay? anyone know of have info? Company didn't respond to my queries.
Mine is 1.5 years old and has not moved with ND winters and is still holding the slab up. I am not sure how long it will last but I know when I use it to seal up cracks in the house the stuff lasts a long time. Thanks for watching.
Expansion joint foam should’ve been completely removed, and filled with fast setting cement like quikrete.. then put a thinner controlled joint. Since the small slab isn’t supported on the edges, it’ll just sink again.. it needs support from the rest of the slab
Absolutely! I use backer rod plus high-flex self leveling sealant to keep water out of my control joints. A bonus is I don't get weeds & debris in those areas.
So far so good. It survived the winter and is still level. I have done this before and it seems to hold up pretty good. The key is to use a lot of foam to get even coverage across the whole slab.
I owned a concrete leveling company for 10 years. If their estimates are that high you must have a completely empty porch. You could possibly replace the concrete for that price
Same question. I'm assuming mine is dirt filled with slab on top. Downspout discharging next to one corner for a couple of years caused movement. One corner of the slab is lower than the top brick step to the porch. Rain gets trapped on porch & often goes in seams between house & slab where I obviously don't want it.
@@dantrumphour3068By empty, do you mean that nothing is under the slab? I have a raised slab porch with about 3 steps to access it. From the crawlspace, I see CMU / stem walls. I'm assuming my porch is filled with dirt (or something). But one porch slab corner is lower than the top brick step. A downspout discharged in the soil at that corner. I've remedied that, but want to correct the slope of the slab so rain doesn't continue being trapped inside.
I've used sand under the sealant, conforms to the varying widths of the joint. I've also used backer rod for the wide areas, followed up by sand to seal it up.
I believe the foam with work but next time you back over with something heavy I think it will sink again. I though you were going to lift it with the foam.
How does it hold up after a year? Another guy from another channel tried and it drop back down so I am not sure if this DIY foam really hold up the cement.
@@jackofalltrades7822 thank you for your reply. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-5U63uGKCvLQ.htmlsi=g1MPU5ne2ve5a_mY is the link that I watch the review of the fix. At about minute 2:18 is when he said that the slap sank back down. At about minute 1:15 is when he reviewed his fix from the previous video.
@@jackofalltrades7822 I have a small slap that sink probably due to the tunneling for the sprinkler valve lines so I am torn between your foaming method or just try to lift the slap and pack as much dirt back in.
@@jackofalltrades7822 @GotthilftIMMER Great Stuff also makes a green colored can called "PestBlock". It has something mixed into it to deter pests from digging through it. Might be helpful to prevent ant colonies and other insects from turning it into swiss cheese.....just a thought. Loved the process btw....thanks for posting the video!👍
I tried that and it didn’t hardly move. Even the Jack struggled. I have done it with out the Jack on other slabs and it did work. Thanks for watching and the comment.
A year later, his is this repair holding up? I need to do something on a “rocking slab” it’s not cracked or anything yet just rocks when you drive over it. I ask because the Big Gap stuff is not recommended for ground contact.
Next time don’t use an expansion anchor/red head. Use a Hilti or Simpson titan screw. That way you don’t need to cut off your red-head and stare at a piece of all thread cutoff.
gotta say like that technique, will keep it in mind I think I prefer to use the great stuff profesional can and sprayer, though I do a fair amount of spray foaming, I find the product and the reusability of the can great, do not though do not try to remove a full can it does not self seal once open. WTF?
Did you Jack up the slab first and the let it sit for a while to let the foam cure before removing the Jack? Nothing should come out of the drilled holes.
Since there was nothing wrong with the slab this was the easiest and cheapest option. Breaking it out, hauling more sand for the base, rebar, mixing in a wheelbarrow, pouring, screeding, finishing, and clean up would have taken several hours. This took me less than 1 hour. More than 1 way to skin a cat I guess.
@@johnbeckwith1361 It was so small🤣 he paid 11 bucks per tube on loctite , 13 bucks on gap filler etc etc.....few swings of the maul , tamp in a bag of gravel and a few bags of quickcrete...roughly 30 or 40 bucks and have it look new!!! Versus something that looks like pure crap "IMO" and more $ plus time. That caulk will not ever look good nor be as good as a solid slab, But if swinging a maul and breaking a sweat isnt your thing...spend more and have it look like 💩!! I wasnt stirring the pot , but its people like you that brings real people like me to the front!!!! Thx for doing that . Do it right 1 time. Now you can return to your easy chair, have a great day!😉
@Rob Turner Why so passed when someone, like u did, expressed their opinion on the matter? What is the cost to dispose of the 400lbs of broken concrete?
Why not lift the slab, create a form along the side and use self levelling concrete underneath or even just pushing soil underneath? Foam is going to compress over time and is only a temporary solution...
@@jackofalltrades7822 Give people what they pay for, if they want foam or w/e.. There are other alternatives.. but whatever.. I don't think the soil was compacted enough, nor was self levelling(wet) concrete used underneath.. A lot of times it is rats building nests underneath that cause sink holes to form amplified by water erosion... I would not be surprised if you get call backs after more time passes... I do hope you don't though and all is well... just spitballing ideas and glad you at least consider them.. thx 4 reply.. Some people try to criticize a "Jack of All Trades, Master of None" but before they finish I correct them and say that a Jack of ALL Trades is called an Engineer! 8D
@@maxmanx1294 Can not post links or comments get deleted. The foam method in this video works well enough but you should explore all your options. I am no pro at this.. but you can use a carjack or boatjack to lift the cement pad a bit over what you need to give space for settling.. You can use "wet" cement so it flows easy & self levels or you can overfill with compacted dirt allowing cement pad to settle on top..
You inspired me, I pretty much exactly copied you. I had a bad sinking slab on my front walkway since I bought the house 3 years ago and it has tripped several people that I know of. I lifted a 10ft by 40” slab today and it only took about an hour, the longest part was filling all the voids with foam. Thank you for this video. I watched dozens of videos on how to solve this problem and this video was single handedly the video that made me get a parts list together and go do it. If you’re interested i posted a short about it. ru-vid.comXuZxhJiHAIE?si=OqGMWr0NvquI5X0X
That is awesome. That is a huge slab. I would be very happy ntesested to know how it holds up over time. Mine is doing great but it’s not nearly that big. Nice job and I liked your short.
I just checked on it and the foam expanded it up another inch😢. So it went from being 3” too low to 1” too high. I think I went crazy with the foam though because i had to use 11 cans since the lift was pretty drastic. I parked my truck wheel on it overnight hoping that helps. The slab sinks a bit every year anyways so maybe it’s not such a terrible thing. I’ll probably grind the corner a bit to smooth it out. 86$ for a huge improvement is still worth it in my opinion. At least until i can budget out an entirely new walkway
Why didn’t you show the rise of the concrete slab when you spraying foam through the holes? That’s the most important part. I never saw any difference in the video. How many cans did you use?
The foam doesn’t raise the slab. The Jack raises the slab. See 5:00 into the video. The foam doesn’t have the needed pressure to actually lift the salad so that is why you need the Jack and boards. The foam simply fills the void. I used 2 cans of foam. Thanks for watching.
Quote, " The foam doesn’t have the needed pressure to actually lift the salad." I assume salad was a typo intended as slab. You apparently assumed that the pressurized single-part foam product can pressure was insufficient to lift your project's slab, but that assumption was wrong. Let's assume that your project slab is 1/3 foot thick so it weighs about 50 pounds per square foot which is about 0.347 psi. Pressures in those 2 cans were many times that value. So it would have performed your lift without your jacking system. The open-cell cured foam they produced can also support much more than that slab weighs. I believe the repair would be even more durable had you used closed-cell foam. As I see it, your external lifting and positioning method produced a really excellent finished position compared to your target position. Lifting by expanding foam pressure alone is unlikely to be quite so accurate.
@@informationsponge5697 In other words the expanding foam in this video did expand but was only allowed to expand to the height of the jack lift, at that point, any additional expansion only pushes foam out of any gap to relieve the pressure.
Seriously? It’s really a simple two-bag concrete repair. A couple of whacks with a sledge breaks it out, a piece of lumber, two pins, a strip of expansion. Done but for the cure. One lazy afternoon.
A two bag repair? A section of concrete 4’ x4’ x 3 1/2” is 4.66 cubic feet. That would be sixteen 40 lb bags, eleven 60 lb bags or eight 80 lb bags. Also the color wouldn’t match if you used bagged concrete. Mud jacking or expanding foam jacking is the quickest, easiest and standard repair. Especially if it is not cracked.
Wadded up paper towels @10:45 ?!?! Ur kidding right ?? Why not use bubble gum or tampons ? It's called, Backer rod, and it's sold at every big box hardware store on the planet. I'm not hating on ur video, it takes balls to put urself out there, but even a small amount of research before you post could save someone else time and money.
Yes, have have used wadded up paper towel in a pinch. I also said to use foam which is what backer rod is made of. Sorry if didn’t used the technical term of “backer rod”. My bad. Thanks for watching.
Sand works well, too. Interesting about tampons. They swell a lot when wet. Now I'm curious about trying them as temporary fixes while I run to the store or wait for parts & supplies to arrive. 😂
I would have enjoyed your video more if I had not had to put up with your firearms BS in the introduction. If you want to do a 2A video go ahead but keep it separate from your DIY stuff.
So let me see if I understand this. Your enjoyment of the video was lessened due to a 30 second video of which 12 seconds was of me firing a gun? I also do gun reviews. I don’t do 2A videos. Have a wonderful day.
@@jackofalltrades7822 I love Pew Pews!!! Add all the Bang bang u like ,maybe he jus "WOKE" ^^^^^🤔😂 , oh and I wasnt bashing your video at all ....jus my opinion
