How To Fix a Concrete Foundation Crack | This Old House 

I've been watching this old house since I was six years old. I know this show is the reason I can pretty much fix any issue I have in my house. Currently, I am fixing a crack in my foundation and afterward, I am going to lay LVP in the entire house. At the same time, I will be installing new toilets in our bathrooms. This is all thanks to This Old House.

As a professional basement waterproofing contractor for over 20 years there are some misconceptions in this video. The high PSI of the epoxy isn't a good thing like noted in the video. Where we are located (Central Massachusetts) we have a pretty horrendous freeze thaw cycle and a seismic load. Meaning the foundation moves, the footing moves, and the ground below the foundation moves. All at slightly different rates. Epoxy dries harder than concrete, so it ends up cracking when the two sides of the foundation move. This is why most injections come with a 5-10 year warranty. There is also the polyurethane approach if you have active water coming into the foundation, those systems usually last between 7-10 years. If at all possible you want to seal it from the outside, with a patch that remains pliable and moves with the foundation. We dig the cracks up by hand directly down to the footing and seal them in a day with a lifetime warranty. The only time we inject is when there is something on the outside (precast steps, deck, stamped concrete). Sika is a great company and they make really good sealants but its asking a lot of epoxy to seal a foundation correctly. When we dig up foundations that have been injected they always have bug holes and pools of material on the outside, so its just a matter of time before they leak again.

I am a structural engineer and this is an excellent video of crack injection. However one of the most important things when fixing concrete cracks is to determine if the cause of the crack is still active. Generally cracks can be classified as active (cause(s) still present) or inactive (cause is no longer present). The video mentions fixing outside drainage which can be the cause but it is hard to know for certain without monitoring the crack for some period of time. Of course crack monitoring over time is not always possible in every situation. In this particular video it looks like an exterior stud wall is sitting on the foundation and there is no floor at the foundation level. Typically in residential construction there is a floor at the top of the foundation which serves to support the top of the wall. If you happen to have a similar situation then in my opinion you have more of a retaining wall than a basement wall and the cause of a crack and repairs may be different.

I've had to do this several times on my house as well, over 100 years old, no footing. In my case it isn't drainage related. I have a couple of techniques I developed. At or below grade, I excavate and face drill into the block on either side of the crack for rebar pins. They are left protruding, and then I use stainless wire to stitch the crack and preload the rebar pins. I make a form and fill it with high strength grout to a fluid consistency. This encases everything, including the rebar stickout and the block core. For above grade, I use stainless stitch ties in the grout lines with epoxy. Again, it is sealed, and then I core fill the block the rest of the way. Some backfill, and some stucco, and you don't know it's there. Plus, unlike epoxy which can bond to dirt and dust, this is a mechanical repair. Very expensive and very time consuming, but that's my habit of overdoing things. My goal was use to use products locally available. For cracks at a corner, you can pin the rebar in from the side, all the way to do the top, which makes a really nice fix.

I just did this a two weeks ago. As a home owner it was easy enough for a weekend warrior to do. Cleanup wasn't bad and the fix is amazing. Best foundation repair that can be had for $100 - $150. Only wish TOH had covered it sooner as finding out about it wasn't so easy.

I had to read the SKU number off the box in the video, the product is Sikadur Crack Weld Injection Kit.

The inside dam is only a temporary solution. Go outside, dig to the footing, grind out the cracks on an angle to make an inside V, not an outside V, meaning the crack is the small part and the inside of the wall is the big part. Pressure wash everything, sump the water out of the hole, and let it dry. Liberally apply hydraulic cement making sure to get it deep into the crevice. Slop non-drying roof tar top to bottom, left to right, going about a foot past the crack at each end. Apply a layer or ashphalt based roll roofing to the entire patch. Repeat the roof tar and roofing material one more time. Protect the area from impact when refilling the hole with 1/2" thick styrofoam insulation. Backfill the soil into the hole, tamping it down every 12" or so. The leak is permanently fixed at that point, even if the foundation shifts another 3/8" over next 100 years. Fixing leaks from the inside only works until things shift a tiny bit. It doesn't matter that it's denser than concrete. Once it loses grab on the crack you're screwed once again. Digging sucks but it makes the fix permanent.

Does anyone else find this therapeutic as well as informative?

I didn't know this incredibly effective fix was available. Great demonstration.

Before my Father sold his 20 year old home, he had about a 6' crack in the poured concrete wall that leaked water when it rained. We found a local company that chipped away at the crack and filled it with epoxy (looked like expanding foam) for only $250. The strange thing was, they drilled into the crack diagonally, and placed maybe 8 or 9 of these metal fittings in to the wall that looked identical to grease fittings, as in, they were one way check valves. Then they covered the crack with some other type of sealant or epoxy that was somewhat of a tan or beige color. The repair also came with a 10 year transferable warranty. Not bad for only $250, and certainly solid peace of mind for the new buyers!

I did the exact same thing to a house I had. When I did it , the epoxy pushed all the way to the outside wall. Still worked liked a charm. It never dripped another drop

Guarantee Hugo only has to ask for payment once when the job’s done.

I just completed a floor to "ceiling" foundation crack repair via this method yesterday. It's a simple task using the same method and results are the same but mine was a bit messier because the epoxy which adhered the ports and covered the crack was two part manual mix. Smelled horrible but bonded like steel. In order to assure the holes wouldn't be blocked I took a long, thin screwdriver and used that as a guide. The injection went pretty smooth at about 3 minutes to appear in the next port. I was amazed that the repair took both tubes but that also gave me a bit of confidence that the entire crack was sealed through & through. I also took care of a drainage issue that the previous owners neglected over that past 20 years. This type of repair is easily completed by a home owner. Just be sure to follow the instructions.

I really liked this,, I have several cracks in a solid porded foundation wall as weel as a leak around mu main Copper water supply line. The only leaks that is troublesome in the house is the leak around water supply. Had a plumbing try and fix it from the outside and they said it would never leak but it did anyway. Had a foundation leak company come take a look and they wanted tear up our entire basement around the foundation wall on the inside of the house and just deal with the water as it came in and not prevent it from coming in the first place. We finally just added our knew roof, we have new properly sized gutters coming next, they are 6", we have 4" now, and we will be able to keep the water from running down the face of the fondation and the gutters from getting clogged. This will be a perfect solution to seal up the cracks on the inside of the house for the water line and the garage. Thank you for showing this

What is the product used to fix these cracks? Would have been nice if they would have included the product name for thos eof us interested in using it.

For anyone who’s interested I’ve replaced many dozens of these epoxy repairs that often lasted only a few months. Epoxy repairs are completely inflexible so they frequently fail as soon as the weather changes. I did hundreds of flexible foundation crack repairs and replacements over a period of about 2 years using a urethane system without a single failure.

Nice to see a foundation repaired the right way! Looks great and should last too

I’m always entertained watching these guys. Great videos....the best !

I thought this was gonna be a job my husband and I could do, lol. Basically, call a professional. I love This Old House. I've learned so many things from you all. You are appreciated.

It's a cool video. But as a homeowner I would like to know if water was coming in through it and if this stopped it from further happening. Also, I would like to know what type of contractor to call to fix this. Also like to know if it's possible for me to do this myself? If so, what do I buy and more details would help. There are still some of us who would like to do it ourselves...if we are shown how to do it. Thanks guys!

Can someone list these exact products?

The crack looks a little wider at the top than the bottom, which leads me to think that the foundation has settled on the left or the right or both. They also said it doesn't have a footing.

I never knew i love doing these works until I saw this. this is my hobby now.

Live these guys. Along with Bob and Norm, I feel like they helped raise me.

You're title is exactly correct, all you did was fix the crack. Nothing was done to prevent the wall from again cracking other than improve the outside drainage. Either a rebar reinforced footer needs to be added or 3x2x1/4" C-channel bolted along the length of that wall.

Could someone list the materials used? I'm buying a house and it has foundation cracks and to keep costs low I think its something I could take on

America is a great country....let's stay together folks and don't let anything divide us

Man i love this show!!!

THE GUY IN GREY LOOKS LIKE YOU COULD TEAR DOWN THE WALL WITH ONE HAND......LOL

That was an excellent demonstration.

Good work, I know epoxy what you mentioned to cover the crack but what is the name of injected material you injected in crack which hose 9000 psi? Thank you

What if the crack goes , visibly all the way through? Do you port and put the first calk on the outside as well, or just the first calk or something else?

Could you put a link to the products used? I sure need a fix like that. Thanks

This stuff works well. I used it and it stopped the water coming into the house. Been about 2 years now and still holding

We used a system that drilled holes off to the side, similar to horizontal drilling in the oil industry. They used pressure to inject there product.

How can I do this without a kit????? I see that these polyurethane foam injection repair kits are expensive! I also see that I can buy packages of the injection ports separate online. Does anyone know if I can just use the ports, some spray cans of foam, and some hydraulic cement instead of the epoxy paste to do this a lot more cheaply? My concern is that spray foam will not have the necessary injection pressure to fill small cracks that a caulk tube of foam would have when injected with a caulk gun would have. And I can't find anywhere to buy polyurethane foam in a caulk tube separately. Please help!

If the crack goes all the way through to the exterior should we do the same process outside?

Great video! My foundation is made of cinder blocks. So if I have a crack in my foundation and inject it with epoxy, should I worry about all of the epoxy going into the large hollow spaces of the cinder blocks?

Interesting, I noticed they didn't mention the cost and other types of methods that could be used.

Epoxy injection is the older technology used for concrete foundation crack injections. The newer kind is a polyurethane injection, which is exponentially more flexible for the expanding and contracting over the season changes. It is slightly more expensive, but not by much. You're looking at maybe $40 more per 10 linear ft of crack.

What's the Sika cartridge material you use to seal the front face of the crack please (troweled on the front face)?

Would be interesting to see them epoxy 2 big concrete blocks together and then pick it up with an excavator on one side, and smack it around a bit. Then the strength will be truly visible.

Kevin is allowed to turn the heater on!

May i ask what kind of epoxy did you use?. Is there a specific one for concrete? Some special features? Or just any epoxy would do. Thanks.

Compare to using hydraulic cement to fill the cracks, what’s the difference? Which will be a better idea?

I have a foundation Crack in a basement wall that is fairly large at the top. We had a structural engineer already pass the wall for repair but I'm wondering how a very large Crack repair would be completed.

💥 I’ve learned all throughout life… When you plug a leak in a dam you do it from the side where the water is pushing from. In this case you would plug it from the outside. This way will just cause the foundation to fill up and hold the water in it.

They did this video 5 years ago. Hugo outdid tommy!!!!

Looks good, BUt Im concerned with the product coming out the back side or outside wall. Wouldn't the epoxy just push through to the outside ? Or would the dirt hold it ? I dont want to dig up my driveway and patio. Thanks for any help

I would like to know the name of the inserts being used, the name and brand of the product being use as well as the name of the tube/hose being used to inject the product. Also, is it just a regular caulking gun being used? Thanks

Thanks for the video. Is the epoxy the older technology compared to FlexiSpan and polyurethane

Silly question, but is this something someone with little to no experience could do by themselves? I've got a couple small cracks in my garage (where one has started to leak through).

Troy Mclure had an excellent video on this same topic.

How much does this cost generally for that size wall crack.

Yeah! I don’t have concrete cracks but it’s awesome to see them fixed! Epoxy is stronger than concrete and if the wall breaks again it could be right beside the epoxy fix. Great demo!

My basement has a crack running horizontally at about a 15° angle from one side pretty much all the way to another. Home constructed in 1950 with terra cotta footer drains running around the perimeter outside. All those clay pipes are cracked due to root invasion, not to mention freezing and thawing each year. I know I’ll have to repair/replace the drainage in addition to the crack injection, but my question is what is the success rate of the crack injection on horizontal cracks vs vertical?

i luv houses

That red and yellow sure does look like Sika.

It doesn't look like a crack caused by lateral soil pressures from the outside. The wall would likely tilt inwards if there was high enough pressure from the outside. The wall is flat across the crack. One side of the crack is not tilted in more than the other side of the crack. The crack is wider at the top than the bottom. It is more likely due to differential settlement. It could be a shrinkage crack but in that case, the crack is usually the same width top to bottom. The crack itself is usually not an issue that has to be repaired. All houses with concrete foundations have shrinkage cracks unless it is a prestressed foundation which is pretty rare. I would look for signs of differential settlement before fixing the crack. You actually don't need to fix the crack itself. If there is an issue with the crack it would be letting water in. Waterproofing and drainage from the outside is more critical to fix. Fixing the differential settlement is more of an issue but the shape of the crack would indicate that more investigation is required.

Thx for sharing, what's the name of the products?

Epoxy is only a bandaid. Stuff will crack and blow out as the wall keeps moving

If it wants to move then let it move; or it will just break somewhere else. I would use expanding foam to make it look nicer.

i have a gunite hot tub that has cracked about 10 inches below the top of the circular pour. the crack is just at the height of the spillway completely around the tub all the way through to the outer side wall. i have searched and searched and am unable to find any type of repair on the internet. i was wondering if this system would work to repair and seal the leaking crack right on the waterline. the crack leaks roughly 50 gallons a day and is behind the tile. i was thinking to use this system, cover with the paintable water proofing material, then retile and grout, then texture and repaint the outer wall.

Would you let me know what you used to seal the cracks my foundation is terrible. Thanks

What is the name of the epoxy being used if anyone knows by chance, or is there one just az good. Thanks

so that neet but you fix drainage patch the creak and the fill that into the creak will stringer than the concrete but there got be some distance from bottom to concrete right and fill the top you not do the bottom then later it’s start busting around fix or in same spot even fix the water drainage there still void at the bottom and move on hot or cold or weight i just thinking

Is there a supplylist somewhere? what the things are called the using? What kind of epoxy And what are those little discs called?

Lol at the guy working while they talking.

after the repair. what needs to be done next? does the house need to be lifted? new floor joists?

anyone know where one can buy this?

What would you recommend to fix a vertical crack on a concrete column that’s holding up a basketball net?

Hi I have a cracked foundation can you please tell me what is the name of the epoxy that was used on this show

Thanks for the great tips...

So what's the name of that stuff?

They're talking about the compressive strength right? Doesn't that not apply here though? It's tensional forces that open up a crack. I have no doubt the epoxy is very strong. But isn't the question more about the adhesive strength of epoxy bond to the concrete on either side of the crack?

i need to buy this epoxy kit. Where do i get one ?

It's strong, but will it hold it in place?

I have this problem in my basement the crack goes from the window to almost the floor of the wall. And last week we had heavy rain and water was coming out from there.

So wholesome

Union bricklayers on the job 👌🏻

So ugh.....what are the names of the products used here?? i.e. name of epoxy, epoxy gun, and plastic adapters for the wall to inject epoxy?

Thank you!

Jb weld!

if you dont seal the crack on the outside of the concrete wall water will enter the outside crack and freeze and will open the crack inside in time.

Sounds good, will look into this.

Do you need to do anything differently for the exterior hairline crack?

This seems so different then the drilling in on a v to make sure you get the inside and outside. Is this better or worse then that method? The one I had done in my basement he cleaned out the crack and used a mini jack hammer to make a V then drilled holes in an x across the hole so that the hole he drilled intersects the crack half way through the hole. he then put adapters in these holes with a locking piece and a ball-bearing on them so it could only flow one direction then injected the crack with acid to clean out the entire crack of all debri out of the whole crack. then he rinsed the entire crack using the same nipples ill call them.. then he injected the resin.. this way the resin was all the way through my wall and the crack as he sealed the whole crack before injecting. This method looks like it only gets the surface of the crack because it can ozze up and does not go further in the crack...

Any one know that type or brand of epoxy he was using in the video?

my question...can crack expand after repair, may be in few years?

What’s the name of the product you used on the wall?

Would be nice of you to post links to materials used. It's definitely a DIY candidate

So does it matter if you start from the bottom or the top ?

At what point do I parge the lathe?

Wow that stuff is strong

I like how Tommy if acting like he doesn't know how to fix that

Sweet Hilti grinder.

Wow I learned so much thanks

I can’t find that Sika product anywhere

There's 2 types of concrete: concrete that cracked and concrete that will crack.

How do we know what materials he is using?