I had an addition added on to an existing structure creating two separate basement foundations. What would be the best way to seal the crack between the two structures to prevent water seepage? The crack is probably under one inch in width. Epoxy resins, hydraulic cement, etc…. . Product recommendations would be appreciated. Thanks!
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Non-shrink grout.
Form around the crack to prevent leakage and pour in grout. Vibrate wall as best you can so the grout gets into all the nooks and crannies.
When set (3 days later) remove the forms and waterproof the exterior side.
Frankie
Thanks for the response! I don't think I could waterproof the exterior because there is soil. Is it necessary to waterproof that portion, will the grout be sufficient?
I suggested non-shrink grout because it's pourable and thin enough to flow into the crack. an alternate material would be hydraulic cement, which, as it dries it swells, making a watertight joint. This would have to be applied by hand, no formwork or pouring. Apply and pack. Repeat. 1" at a time. A 1/4" and 1/2" tuck pointer trowels are needed.
https://marshalltown.com/pro-1585-tuck-pointers
Frankie
You might consider some sort of bonding agent, such as Concrete Adhesive.
https://www.quikrete.com/productlines/concretebondingadhesive.asp
Not recommending the Quikrete product, just giving an example.
thanks! will look into it.
I saw this question a few days ago and thought the obvious would be posted.--so I didn't give my suggestion. I see that your question is still here.
Have you considered one of the many crack injection sealant systems available? Here is Sika's version at HD.
https://www.homedepot.ca/product/sika-concrete-crack-injection-fix-kit/1000172324
I don't recall if I used Sika or another brand to fix a crack in my basement wall. Very easy to use and three or four years later it's still as I repaired it. Glue on the injection tubes with hot melt. Apply the special bonding cement over the crack and to cover the injection tube flanges. Starting from the bottom, inject the expanding foam into the tubes. Very easy. Basement wall repair contractors charge an arm and a leg for this same procedure.
I'm just not sure that you'll be able to get grout, as others have recommended, into the full thickness of the joint. This is where the expanding foam is advantageous.
The system is a bit expensive for wide cracks but perhaps you can partly fill it with sill plate foam seal.