Home>Discussions>EXTERIORS>Foundation repair help, please!
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mollywobbles
Foundation repair help, please!
mollywobbles

My 1911 house is surrounded by concrete. There is a small gap between the concrete and the foundation. In the past this has been caulked-I believe with a couple layers of silicone--and it is now weathered and cracked. I am cleaning out the silicone and plan to replace with polyurethane concrete crack sealant, using foam tubing (caulk-saver) where needed. In the older part of my house the basement wall is crumbly inside. I am finding about a 6-7 foot stretch on the outside where the outer smooth covering just above the cement driveway is gone and was apparently filled in years ago with caulk-like stuff and painted. In removing the crack seal, it is pulling away the repaired area in patches about 2-4 inches wide. Underneath is the old,coarse concrete.
I am retired and cannot afford to do much more than a repair to protect the outside. I read elsewhere here about using ThoroSeal. Would something like this help? And if so, how do I know which of their products to use. I am really concerned about freezing temps, which we are due fairly soon.

dj1
Re: Foundation repair help, please!
dj1

1. Concreate sealant in a caulking tube or elastomeric caulking are good seals for narrow cracks (1/4" or narrower).

2. For wider gaps (like you have, 2-3"): (a) clean well and remove all dirt, trash, old caulking, etc. (b) fill with mortar (cement and sand mix). (c) when dry, brush ThoroSeal (mix it with water till it's like paste, then brush it on).

Follow the instructions on the bag carefully for best results. ThoroSeal is sold in masonry supply yards.

There are other products just as good out there. I've just had pretty good luck with ThoroSeal as moisture blocker.

If you do it yourself correctly, you can save money, but do it wrong, and it will cost you double.

mollywobbles
Re: Foundation repair help, please!
mollywobbles

No Thoroseal within 100 miles! I took the product info sheet to my local guy, who is a contractor turned building supply store owner. He showed me a comparable product,with its companion bonding agent additive, that he has used on his own house. I plan to use that. I am still debating about the type of caulk to use in other areas that don't need the concrete patch along the driveway/wall base crack. My research ****** said silicone does not have the lifespan of polyurethane or acrylic/elastomeric. I got the polyurethane masonry sealant as it seemed best for what I need, but I understand that it is thick and more difficult to work with, as well as not cleaning up with water. Any thoughts on this?

dj1
Re: Foundation repair help, please!
dj1

If you can't find Thoroseal, take this contractor's recommendation.

For the small cracks choose the elasto caulking. It will probably give you years of decent caulking.

mollywobbles
Re: Foundation repair help, please!
mollywobbles

Thanks for your help!

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