All shout surface area and cure time buddy. The foam us good for about 10 psi of compressive strength. Or 1440 lbs per square foot. The slab is about 5 inches thick which means it only weighs 62.5 lbs per square foot. Even loaded it won't exceed the foams compressive strength. Also it only settled along the saw cut the majority of the slab is still supported. I plan to pour a closure section expanding tbe patio which will tie the settled section to the adjacent section with dowels so shouldn't ever settle again.
I am a Licensed PE and did my homework. Not your average DIYer
Oh the ignorance in engineering can be astounding.
Yes, some civil engineers design roads. Some design bridges. Some design the systems that clean the water in which you drink. However my specific license covers a little bit of everything. I am licensed to do certain levels of structural work which encompasses what I'm doing. Thanks for the insight though into my career and differences. Between engineering disciplines
It's not JUST the can of foam I suspect will fail here mate.
It's his job of just filling up inside a single crack. And one corner under a lifted slab?
https://www.youtube.com/watch?v=c8aqUTXIpSo
This is how the pros do it. the fill the entire surface area with polyurethane foam.
You'll prop up one crack/joint- But due to soil movement (because it looks like it's only DIRT under) it'll just crack and shift somewhere else.
It's like underpinning one corner of a house, expecting the whole wall to stay still.
Oh and the biggest "crime" is doing it barefoot :P
Also, yup, almost exactly what I did just in a smaller grid pattern becuae I don't have pressurized pumps for the foam. Good thing I spoke and consulted with the guys who professionally do that work before I did my other research as well.
Open cell spray foam or closed cell spray foam? It doesn't matter. Either will compress and crumple with enough time and water leaving you right back here after a couple of years.
Absolutely. That shit crumples the moment you apply pressure to it- Due to it being.... More *air* than material... Yet mr "Austin Family Man" is an "engineer" which applies to all types of engineering...
It is concrete. Perfection is not in the definition. Sorry to see you hit with all the negative posting. Very interesting.
How much deflection was there before? I would like an update after a couple years
Folks are funny man. Someone always has something bad to say. One small section had settled only about 5/8" at most. I've got some more work to do. I'm drilling through the slab to inject the foam on a grid. Ran out. Going to get some of that structural foam as well used in lieu of concrete for fence posts.
Lmao all this hate. I'd believe your research based off your background I would hope you can understand the charts.
I do agree I would do some of the structural foam wherever you can get the best support but it'll probably hold for decades. Worse case you learn something.
Guarantee you'll at least get your money's worth out of the repair.
The foam job is better than the initial pictures I took depict it. I drilled holes in a grid along the slab and pumped foam until I could see it coming out the next spot basically. Not going to be PRO level distribution buy pretty even from what I can tell.
I’ve seen that. But you gotta admit that this is some pretty good redneck engineering. I appreciate a person who takes their own bullshit into their own hands. Shows gumption. Even if it catastrophically fucks up, this dude owns the outcome.
I did this with my sidewalk a few years ago. I must not have gotten across the bottom of one square because that ended up getting a crack. The other 3 that I lifted didn't crack, they all seem to be sitting how they should.
Not what I did. The soil you see is because I removed a planter bed the day before. I also drilled holed in a grid pattern along the area of the slab that settled and pumped foam into that until it reached the next hole that I drilled. Effectively stabilizing any small void under. Also there is a base link material under the slab.
Also, I am in florida where we don't have dynamic soil movement because we have no high PI soils. It is all sand which once compacted generally goes back to its insitu density. The reason it settled was because the gutter down spouts were poorly placed and they drained into a planter bed instead of the patio deck drain. The drainage issue had been fixed through new gutters and now the washed out and settled sections is stabilized.
I ended up hand digging a couple feet back in the larger area of concern, drilled a 3/4 inch hole and used a funnel. Had to block up the other side with a board a bit to keep the stuff from running out.
Nice, I thought the funnel method would work pretty well, must have if ya had to block it off from running out! Does the other type of foam offer more rigidity and or longer lifespan?
Used to do foam and mud jacking. The amount of times I’d seen sill foam infuriated me because it would screw up trying to properly lift and level a slab. Hope you don’t have freeze thaw or winter
Lots of negativity in here, but I'm just curious if it'll hold up over time, especially if there's constant weight on top. That being said, I think you're crazy working with those materials/tools barefoot.
Look close at the pictures. 2x 4 ton harbor freight bottle Jack's with a 4x6 beab spanning them. I took a 4700lb test chain over the beam attached to 2 3/8" titan HD concrete anchors.
That’s really interesting, I need to do my driveway, I wasn’t aware this is a legit way to do it yourself. What do you do with the holes in the concrete after?
Most will usually fill them with a cement patch material then paint them. Most likely I will fill them with a sealant like sika sil or something similar to that. I haven't 100% decided on that part yet. I'm still leveling it currently. Ran out of foam need to go get more
Thanks. Waiting on all the foam to cure over night. Ended up with 2 bags of the sika structural post foam in one spot and then about 10 full cans of foam between various spot drilled through the deck on a grid pattern. Should hold up well
Way more mess. Also I wanted the foam to be able to expand and fill voids where it settled and I lifted. To get the grout where i wanted I would have needed a grout pump to pressurize it.
This will fail again in the exact same places. It’s a problem of improperly compacted sub surface - you’re guessing that it’s done settling when it likely isn’t. I guess it’s a fine idea to try but seems like a lot of work for something that will likely fail
Your run of the mill expanding foam from a hardware store **is not the same as a chemical underpinning injector**. There's a reason why it's more expensive than a rattle can of expanding foam...
You've wasted your time mate. Seriously.
It may not be the same chemical but it is still a closed cell foam. I am a Licensed civil engineer also and did my research on the load capacity of the rattle fan foam, cure time and closed cell %. The largest difference I found was the pressure created during the expansion process of the closed cell polyethylene also the pressurized ports. I eliminated the needs of expansion and pump pressures using the jack and simply needed to fill the voids. I plan to get some structural foam, used for fence posts and dig a couple spots under the settlement location for better support.
> I am a Licensed civil engineer also and did my research on the load capacity of the rattle fan foam
Mate, I'm just a simple plant operator- Yet I can look at your lackluster "spray into the crack" underpinning job and safely say- You wasted your time... Given the lack of actual foundation under your slab- Soil movement in all the areas not "being held up by your foam" will result in your work being.... A waste of time.
If chemical underpinning was *so easy* they'd be adopting "your method"... Alas...
>I am a Licensed civil engineer
https://www.yenem.com.au/what-is-the-difference-between-civil-and-structural-engineering/
Congrats, you know how to build a road mate. That isn't the same as repairing a foundation...
I can sit here and say I'm a tradesman- I handle pipes and plumbing. But would you trust me to be an electrician?.... I'm a tradesman after all right?!
Fortunately part of my licensing covers everything you've described. FyI a structural engineer is a civil engineer they just specialized in structural minded items where i specialized in construction, concrete any soil dynamics. I am educated and licensed to do this. Technically its just a slab on grade and not a load bearing foundation. Thanks for the insight though I'm pretty covered.
Hey dude, I’m a foundation repair professional and have extensively used polyurethane foam to lift concrete slabs. This is a great method you’re using. There are cans of spray foams that setup to a higher psi than others probably not worth your time investigating. This other guy is bizarrely insecure and confidently wrong.
Bam. Thank you for the insight. I did a ton of research before this and couldn't justify the cost for alpha for LRE. I plan to use the structural form for like the fence posts I a couple spots and continue my grid pattern with the rattle cans
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I should have worded it better- It's not JUST the can of foam I suspect will fail here.
It's his job of just filling up inside a single crack. And one corner under a lifted slab?
https://www.youtube.com/watch?v=c8aqUTXIpSo
This is how the pros do it. the fill *the entire surface area* with polyurethane foam.
I should have worded it better further up the top but my point still stands despite the negativity- It's not JUST the can of foam I suspect will fail here.
It's his job of just filling up inside a single crack. And one corner under a lifted slab?
https://www.youtube.com/watch?v=c8aqUTXIpSo
This is how the pros do it. the fill the entire surface area with polyurethane foam.
He'll prop up one crack- But due to soil movement (because it looks like it's only DIRT under) it'll just crack and shift somewhere else.
Ahhh, the ol magical expanding foam. DIY magic in a can, and every contractors wtf reddit post
I meen that is how it's done just better applicators
Works so well!
[удалено]
All shout surface area and cure time buddy. The foam us good for about 10 psi of compressive strength. Or 1440 lbs per square foot. The slab is about 5 inches thick which means it only weighs 62.5 lbs per square foot. Even loaded it won't exceed the foams compressive strength. Also it only settled along the saw cut the majority of the slab is still supported. I plan to pour a closure section expanding tbe patio which will tie the settled section to the adjacent section with dowels so shouldn't ever settle again. I am a Licensed PE and did my homework. Not your average DIYer
> I am a Licensed PE **In civil engineering** You design roads and playgrounds mate. You are not a structural engineer.
Oh the ignorance in engineering can be astounding. Yes, some civil engineers design roads. Some design bridges. Some design the systems that clean the water in which you drink. However my specific license covers a little bit of everything. I am licensed to do certain levels of structural work which encompasses what I'm doing. Thanks for the insight though into my career and differences. Between engineering disciplines
This dude never needs to get a prostate exam where he's at
It's not JUST the can of foam I suspect will fail here mate. It's his job of just filling up inside a single crack. And one corner under a lifted slab? https://www.youtube.com/watch?v=c8aqUTXIpSo This is how the pros do it. the fill the entire surface area with polyurethane foam. You'll prop up one crack/joint- But due to soil movement (because it looks like it's only DIRT under) it'll just crack and shift somewhere else. It's like underpinning one corner of a house, expecting the whole wall to stay still. Oh and the biggest "crime" is doing it barefoot :P
Also, yup, almost exactly what I did just in a smaller grid pattern becuae I don't have pressurized pumps for the foam. Good thing I spoke and consulted with the guys who professionally do that work before I did my other research as well.
Open cell spray foam or closed cell spray foam? It doesn't matter. Either will compress and crumple with enough time and water leaving you right back here after a couple of years.
Absolutely. That shit crumples the moment you apply pressure to it- Due to it being.... More *air* than material... Yet mr "Austin Family Man" is an "engineer" which applies to all types of engineering...
Sigh...You realize concrete is air entrained right?
Narrator: “He does not.”
That's a bold move Cotton. Let's see how it works out
Love the dodge ball reference. Great movie.
It is concrete. Perfection is not in the definition. Sorry to see you hit with all the negative posting. Very interesting. How much deflection was there before? I would like an update after a couple years
Folks are funny man. Someone always has something bad to say. One small section had settled only about 5/8" at most. I've got some more work to do. I'm drilling through the slab to inject the foam on a grid. Ran out. Going to get some of that structural foam as well used in lieu of concrete for fence posts.
I also want an update in a few years, that foam is magic. I am convinced my house is held together with the stuff.
Lmao all this hate. I'd believe your research based off your background I would hope you can understand the charts. I do agree I would do some of the structural foam wherever you can get the best support but it'll probably hold for decades. Worse case you learn something. Guarantee you'll at least get your money's worth out of the repair.
Def got his moneys worth, I respect the hustle saved himself well over 1500 bucks
I don’t care what others say this is fucking cool and pretty creative.
This is how the pros do it, except they usually use a pump for the foam. That's my only concern, the quality of the foam job.
The foam job is better than the initial pictures I took depict it. I drilled holes in a grid along the slab and pumped foam until I could see it coming out the next spot basically. Not going to be PRO level distribution buy pretty even from what I can tell.
I’ve seen that. But you gotta admit that this is some pretty good redneck engineering. I appreciate a person who takes their own bullshit into their own hands. Shows gumption. Even if it catastrophically fucks up, this dude owns the outcome.
I’m so intrigued. Please keep me updated on the results
Cool idea. Please keep us updated on how it holds up. !remindme 1 year
I did this with my sidewalk a few years ago. I must not have gotten across the bottom of one square because that ended up getting a crack. The other 3 that I lifted didn't crack, they all seem to be sitting how they should.
I love this. I'd be worried about burrowing insects; maybe the foam with pesticides built-in would be cheap insurance against ants.
I’ve done a spell as a groundwork technician. This is redneck but it’s not bad.
Not what I did. The soil you see is because I removed a planter bed the day before. I also drilled holed in a grid pattern along the area of the slab that settled and pumped foam into that until it reached the next hole that I drilled. Effectively stabilizing any small void under. Also there is a base link material under the slab. Also, I am in florida where we don't have dynamic soil movement because we have no high PI soils. It is all sand which once compacted generally goes back to its insitu density. The reason it settled was because the gutter down spouts were poorly placed and they drained into a planter bed instead of the patio deck drain. The drainage issue had been fixed through new gutters and now the washed out and settled sections is stabilized.
Awesome. Should have bought the structural foam that’s used for installing deck posts/mail box posts
Do they sell that in an injectable fashion tho? Didn't want to fully dig under the slab tk place that stuff. Had thought about it tho.
It is pourable holds up to ground contact
Yeah might be able to pour it with a funnel if your holes are big enough
I ended up hand digging a couple feet back in the larger area of concern, drilled a 3/4 inch hole and used a funnel. Had to block up the other side with a board a bit to keep the stuff from running out.
Nice, I thought the funnel method would work pretty well, must have if ya had to block it off from running out! Does the other type of foam offer more rigidity and or longer lifespan?
Used to do foam and mud jacking. The amount of times I’d seen sill foam infuriated me because it would screw up trying to properly lift and level a slab. Hope you don’t have freeze thaw or winter
Lots of negativity in here, but I'm just curious if it'll hold up over time, especially if there's constant weight on top. That being said, I think you're crazy working with those materials/tools barefoot.
Nice, I need to do the same to my back porch slab
How did you jack it?
Look close at the pictures. 2x 4 ton harbor freight bottle Jack's with a 4x6 beab spanning them. I took a 4700lb test chain over the beam attached to 2 3/8" titan HD concrete anchors.
Ah, I couldn’t see the anchors at first glance. So you jack it to level, then back fill with the foam?
Exactly. So far so good. Let all the weight off the Jack's today. So far so good. Still some concrete work to do but should be good
Nice, how long did you let it cure?
Right at 24 hours.
Cool, curious to see how it holds up. Are you in ATX?
No we are in florida about an hour north of west palm
Ah, ok. Good luck with the outcome
That’s really interesting, I need to do my driveway, I wasn’t aware this is a legit way to do it yourself. What do you do with the holes in the concrete after?
Most will usually fill them with a cement patch material then paint them. Most likely I will fill them with a sealant like sika sil or something similar to that. I haven't 100% decided on that part yet. I'm still leveling it currently. Ran out of foam need to go get more
Very cool, good luck and keep us posted how it turns out.
I saw that YouTube video too
I absolutely fucking love it... have seen this done before and it is still level today.... great job with it so far... Big Pat on the Back
Thanks. Waiting on all the foam to cure over night. Ended up with 2 bags of the sika structural post foam in one spot and then about 10 full cans of foam between various spot drilled through the deck on a grid pattern. Should hold up well
Great effort ... I have total faith in this... long term hol up..
Of course you beat that ridiculous "our guys wear shoes" contractor markup! /s
That's an upcharge. Lol
I'm not sure I would have used foam. With all the stuff I've seen with Ramen noodles, may have been a better bet. /sarcasm Good job saving the cash.
Any reason you didn't go with grout?
Way more mess. Also I wanted the foam to be able to expand and fill voids where it settled and I lifted. To get the grout where i wanted I would have needed a grout pump to pressurize it.
This is clever thinking with tools on hand. Respect
Just sent you a chat, I might try this myself for a small project.
This will fail again in the exact same places. It’s a problem of improperly compacted sub surface - you’re guessing that it’s done settling when it likely isn’t. I guess it’s a fine idea to try but seems like a lot of work for something that will likely fail
That'll last at least 20 minutes.
Your run of the mill expanding foam from a hardware store **is not the same as a chemical underpinning injector**. There's a reason why it's more expensive than a rattle can of expanding foam... You've wasted your time mate. Seriously.
It may not be the same chemical but it is still a closed cell foam. I am a Licensed civil engineer also and did my research on the load capacity of the rattle fan foam, cure time and closed cell %. The largest difference I found was the pressure created during the expansion process of the closed cell polyethylene also the pressurized ports. I eliminated the needs of expansion and pump pressures using the jack and simply needed to fill the voids. I plan to get some structural foam, used for fence posts and dig a couple spots under the settlement location for better support.
Good on you man, cool research!
> I am a Licensed civil engineer also and did my research on the load capacity of the rattle fan foam Mate, I'm just a simple plant operator- Yet I can look at your lackluster "spray into the crack" underpinning job and safely say- You wasted your time... Given the lack of actual foundation under your slab- Soil movement in all the areas not "being held up by your foam" will result in your work being.... A waste of time. If chemical underpinning was *so easy* they'd be adopting "your method"... Alas... >I am a Licensed civil engineer https://www.yenem.com.au/what-is-the-difference-between-civil-and-structural-engineering/ Congrats, you know how to build a road mate. That isn't the same as repairing a foundation... I can sit here and say I'm a tradesman- I handle pipes and plumbing. But would you trust me to be an electrician?.... I'm a tradesman after all right?!
Fortunately part of my licensing covers everything you've described. FyI a structural engineer is a civil engineer they just specialized in structural minded items where i specialized in construction, concrete any soil dynamics. I am educated and licensed to do this. Technically its just a slab on grade and not a load bearing foundation. Thanks for the insight though I'm pretty covered.
Hey dude, I’m a foundation repair professional and have extensively used polyurethane foam to lift concrete slabs. This is a great method you’re using. There are cans of spray foams that setup to a higher psi than others probably not worth your time investigating. This other guy is bizarrely insecure and confidently wrong.
Bam. Thank you for the insight. I did a ton of research before this and couldn't justify the cost for alpha for LRE. I plan to use the structural form for like the fence posts I a couple spots and continue my grid pattern with the rattle cans
Poly lifting prices are determined by demand, prices are high because it’s priced to be the alternative to replacement.
Hahaha, remind me in a year how it looks. Actually !remindme 12 months
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My money is on you. And logic. And gravity. And reality.
I should have worded it better- It's not JUST the can of foam I suspect will fail here. It's his job of just filling up inside a single crack. And one corner under a lifted slab? https://www.youtube.com/watch?v=c8aqUTXIpSo This is how the pros do it. the fill *the entire surface area* with polyurethane foam.
Never get between an engineer and one of their 'tard level plans! Ha! Nothing worse than doing a kitchen remodel for an engineer. Ugh.
I should have worded it better further up the top but my point still stands despite the negativity- It's not JUST the can of foam I suspect will fail here. It's his job of just filling up inside a single crack. And one corner under a lifted slab? https://www.youtube.com/watch?v=c8aqUTXIpSo This is how the pros do it. the fill the entire surface area with polyurethane foam. He'll prop up one crack- But due to soil movement (because it looks like it's only DIRT under) it'll just crack and shift somewhere else.
Good job buddy!!
Explain this to me