Got me a crack in basement foundation wall

OmegaBravo7

OmegaBravo7

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Been getting slow seepage through the base of the wall in the basement for the past few months. Luckily it’s in the middle of being demo’d so I ripped out that part of the wall. Found a vertical crack from the top down to the base of the wall where it meets the floor - that’s where the water is coming through the most.

Since it’s a poured foundation wall I’m hoping I can address the problem from the inside. I really want to avoid fixing from the outside. The ouside side of the house is all concrete slab flooring with steps. It’s the thickest I’ve ever seen, about 10-12” thick concrete slabs the entire side of the house.

Anyone with any luck repairing the leak/crack using epoxy injection or polyurethane injection? I’m pretty handy myself - or should I hire someone for it? And which is the better and best option of the two, epoxy or polyurethane injections?
 
Check your foundation drains are clear?
It's possible that it was hydraulic pressure made that crack, and sealing it could just allow the pressure to build again until it cracks somewhere else or blows out the repair.

If you want to try a diy repair, the old school way was bentonite clay and a grout pump.
Bentonite is self healing, and if its just seepage could work. Cheap to try, low probability of success.
 
I don’t think it’s foundation drains. We moved in about a week after the closing date because it was so cold with lots of snow, 2 yrs ago. When the previous morons were moving out they didn’t shut off the copper pipe leading to the hose spigot outside had burst - the spigot was blown right off. For a few days water was pouring under high pressure just like you’d expect when a water line breaks wide open. When I arrived the basement was full of water. I believe what happened was the water along with freezing temperatures caused the wall to crack and it’s been seeping ever since.
 
Poly injection, hydraulic cement is also water proof. Seal off with redgaurd. Problem just sealing from the inside is you still have a crack that water can get into and freeze and expand the crack further.
Pain in the balls but digging outside and doing a tar coat with dimple plastic is the best bet to ensure it's sealed.

To just seal it for now. Redguard is amazing. Even drys while water runs over it. Home depot carriers this.
 
Ok, good chance that bentonite might work then.
Rather than using a grout pump,
just wondering how much pressure is really needed to get it to the other side. A one off job like this you might be able to do by hand. I might try drilling 3/8 holes 3 inches into the crack and pump bentonite slurry or hydraulic cement using a caulking gun.
Never tried it myself but same principle as power grouting. Cost 40 bucks and your time.
 
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I’ve used red gaurd, great for moisture prevention purposes. I wouldn’t use to block off water, like you said that’ll just prevent water from entering basement but the water will still enter the crack and cause further damage. The epoxy and poly when injected into the crack, I believe, expands all the way through to the exterior of the wall completely curing the problem. The issue I’m having trouble finding out is which is better for vertical poured foundation cracks, and if it’s ok to use while it’s still freezing temperatures outside
 
Whats the diff between poly and bentonite? Is the bento a surface sealer or does it penetrate the crack completely to the opposite side of the wall?
 
As a temp fix, poly injection and hydraulic cement will seal it from the inside and limit its growth. If you some skill and time, most can perform this task and should take 1 day if an avg crack (1/8” +/-). Key is to grout the tubes into place and be sure the grout has set before injection. make sure the crack is brushed clean with a wire brush before attempting to inject or grout.

Best to excavate the exterior, tar/bitumen’s sealant and dimple wrap (Delta etc) when you have a chance.
 
OmegaBravo7 said:
Whats the diff between poly and bentonite? Is the bento a surface sealer or does it penetrate the crack completely to the opposite side of the wall?
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Poly will expand to fill/follow the crack with no external effort. Think of spray foam or gorilla glue. if the crack is seeping, this is good for the poly as it will expand more aggressively.
 
the crack is vertical from top to bottom approx 7.5ft. Crack is slim, def less than 1/8”. Only the bottom about an inch off the the crack meets a round 3/4-1” damaged surface where the water is seeping through
 
OmegaBravo7 said:
Whats the diff between poly and bentonite? Is the bento a surface sealer or does it penetrate the crack completely to the opposite side of the wall?
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Bentonite is old school. It is finely powdered rock. It is just a particular type of clay that expands when wet so becomes waterproof if there is water present. Its used to seal well casings and ponds etc. You need to force it through the crack. It is self healing and lasts centuries once in place. It is used in everything from geotextile engineering and in kitty litter.
It DOES NOT work as a surface sealer. It has to be embedded.
Polyurethane is a crosslinked plastic that expands as it cures by incorporating water into its polymer bonds. It is a powerful adhesive to most common materials. It is a poor surface sealer as well for liquid water seepage, but its expansion ability can force it through the crack. Moisture can migrate through it, but very slowly.
 
OmegaBravo7 said:
Pic
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A “standard” differential settlement crack. Typical in older construction or new over inadequately compacted soil beneath the footing. Not a major structural concern unless the two planes push are no longer flush, like one side is moving further into or out of the house.

Poly injection will resolve this but if the crack is not 1/8” it may require chipping the edges away to expose more surface of the crack; then brush and clean with compressed air.

Home Depot (or similar) will sell more than one option, a single crack will not require the whole kit. You can piece it out as 1 box of tubes, 1 tube of poly, 1 bag of grout.
 
My advice is to hire a contractor with a warranty that covers leaks. Get it epoxied or the other substance filled. Then if it leaks they will redo it for you. If it still doesnt work you will need proper waterproofing from the exterior. Most homes are not properly waterproofed from the outside ever and any cracks can turns into leaks. 20+ years in resi construction and i see this all the time, especially recent years where builders did not give a fuck because people were flocking in to buy anything with a roof on it, lol.
Also quick question. You bought this privately i assume and not from a builder?, because youd be covered still. Also, you purchased and the home and it was left in a manner that caused significant damage requiring repairs before closing. Did you not see the place again on closing date? Is there not legal responsibility of the seller for any of this damage? Because it wasnt there pre purchase but then it was when u closed and moved in. Just whos fault was this really? I dont know the legal parts of this thats why i ask.

Because by the time its said and done it could cost you up to about 20k if contractors epoxy it and then have to waterproof outside aswell with all the concrete and digging involved. And then reinstall concrete and soil etc.
 
Lumberjock said:
A “standard” differential settlement crack. Typical in older construction or new over inadequately compacted soil beneath the footing. Not a major structural concern unless the two planes push are no longer flush, like one side is moving further into or out of the house.

Poly injection will resolve this but if the crack is not 1/8” it may require chipping the edges away to expose more surface of the crack; then brush and clean with compressed air.

Home Depot (or similar) will sell more than one option, a single crack will not require the whole kit. You can piece it out as 1 box of tubes, 1 tube of poly, 1 bag of grout.
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That is what I did in my first house, then layed a coat of rubbery stuff (can’t remember the name) on the inside just in case I got seapage.
I did have to chip the crack.
I know the person who bought that house from me like 20+ years ago and the basement is still dry.
 
These types of cracks are considered typical cracks. Things that may help....
- ensure all downspouts are directed 8' away from foundation
- Ensure the grade around your house is positive...meaning ensure the ground surrounding your house slopes away from the foundation to give ground moisture a chance to drain away from foundation
- Monitor for pooling water in areas around your house
- Perhaps installing a sump pump may be beneficial depending on water table
 
Unless the seller is required by law to shut off the water valve for the hose spigot I don’t have any legal course. They left, I entered same day, closing date, to ensure they moved all all their furniture garbage and crap. Dude, it was fucking COLD. Nothing seemed out of the ordinary on all levels. I left and came back about 6-7 days later to move in. As soon as I entered I heard a loud gushing from the side of the house sound like running water when filling up a bathtub. I ran back there to find a copper pipe with no end gushing water out. The spigot had flown off. I immediately ran to the basement and confirmed the shitload of water that had entered. Turned the main off, ran to home depot, grabbed a sharkbite end cap, cut end off the pipe and attached the end cap until the basement was addressed.

And yeh man the concrete patio walkway/steps along side of the house is sloped towards the house, not too crazy though. I had concrete fellas come last yr but the quotes were insane. Because it involved steps and because the thickness is ridiculously thick at approx 10-12”. It’s about 6ft wide, 50ft long, and 10-12” thick.

After doing a lot of research online Poly or pu is the way to go. Not only does it fill in all the way to the other side of the wall but it works with a wet crack or actively leaking wall. Epoxy on the other hand requires a certain temperature outside and concrete mist be completely dry.

I may give it a go myself if I can find the repair kit local. I don’t like dealing with contractors.
 
OmegaBravo7 said:
Unless the seller is required by law to shut off the water valve for the hose spigot I don’t have any legal course. They left, I entered same day, closing date, to ensure they moved all all their furniture garbage and crap. Dude, it was fucking COLD. Nothing seemed out of the ordinary on all levels. I left and came back about 6-7 days later to move in. As soon as I entered I heard a loud gushing from the side of the house sound like running water when filling up a bathtub. I ran back there to find a copper pipe with no end gushing water out. The spigot had flown off. I immediately ran to the basement and confirmed the shitload of water that had entered. Turned the main off, ran to home depot, grabbed a sharkbite end cap, cut end off the pipe and attached the end cap until the basement was addressed.

And yeh man the concrete patio walkway/steps along side of the house is sloped towards the house, not too crazy though. I had concrete fellas come last yr but the quotes were insane. Because it involved steps and because the thickness is ridiculously thick at approx 10-12”. It’s about 6ft wide, 50ft long, and 10-12” thick.

After doing a lot of research online Poly or pu is the way to go. Not only does it fill in all the way to the other side of the wall but it works with a wet crack or actively leaking wall. Epoxy on the other hand requires a certain temperature outside and concrete mist be completely dry.

I may give it a go myself if I can find the repair kit local. I don’t like dealing with contractors.
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PU (polyurethane / “epoxy” ) is what you want to use. Expands through whole depth of crack and can be used in a wet location; if dry than mist with water before injection.

Grout the tubes in place and make sure it is set before you try to inject or the expansion will pop the tube off the wall and the PU will leak out.

You can do this, it’s really straightforward and has maybe 4-5 steps total. Wear disposable gloves when injecting…it will get on your hands
 
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