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Waterproofing exterior of basement wall with spray foam

josasjam | Posted in General Questions on

Hi, Recently, I had a problem, my basement wall was bowing in. A company came out and used hydraulic jacks and straightened the wall out. They dug out the exterior and supposedly sprayed a foam on the outside to waterproof. My walls now leak horribly when they did not leak at all prior to their work. They said they could not put a bladder on the exterior because the walls were the old stacked limestone so they used the foam which they said would do the same thing the bladder would.. I called them and now they are saying the foam is not a waterproofer. We insulated the interior and it is sopping wet. Do companies such as this use foam to waterproof? We paid $12,000.00 for this and they were here less than 48 hours. HELP!!!! Thanks

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  1. GBA Editor
    Martin Holladay | | #1

    It's hard to diagnose your problem based on the information you provided. It's possible that your foundation has a structural problem, a drainage problem, and a waterproofing problem. Solutions could range the gamut -- from improved grading (so that soil slopes away from your foundation) to the possible need to replace your existing walls with new poured concrete walls.

    It certainly sounds like you have a legitimate beef with the company you hired, but it's hard to know without seeing what type of contract you signed.

  2. josasjam | | #2

    Thank you for your answer. There IS a drainge problem around the house. We are leveling out the yards and we're doing tiling. However, when they escavacated 2 feet down below the exterior basement wall they found out that the original basement wall had been added to on the inside with poured concrete and the outer wall was the original limestone rock. Therefore, they could not put in a bladder on the outside because that wall was not smooth as it needed to be for a bladder, they said. So, they said they had a foam spray that would waterproof the same as the bladder. That is what they supposedly did. There is copious amounts of water flowing in the basement whereas there was no leakage beforehand. Now they are saying that the foam is not waterproof. That is what i want to these companies ever us any type of foam for waterproofing basements? If I cannot get them to remedy this, is it possible for me to use black jack and watertite on the inside. i cannot even use the basement anymore!! Thank you

  3. GBA Editor
    Martin Holladay | | #3

    I note that you tried to start a second Q&A thread on this topic. Please post all your follow-up questions here on the same thread -- don't start a new thread on the same topic. Thanks.

  4. charlie_sullivan | | #4

    The only foam that I've seen for waterproofing is a foam you inject in a crack to seal that crack from leaking.
    But there may be foams that I haven't see that are good for waterproofing wider surfaces. I would ask the contractor for a data sheet or URL for a data sheet on the product they used, and see what it claims to be capable of.

    Some foundation waterproofing contractors have clear warranty policies, and you might find you have good grounds to insist they take responsibility to fix it. If that's not in writing, it will be harder to establish what they represented to you that they were going to accomplish with the foam.

    It seems likely that the process of straightening it out opened up some cracks to allow the leakge. It might be possible to inject foam or epoxy from the inside and seal those cracks. It sounds like you need to remove your insulation anyway, so you should then be able to see where it is leaking better and see if there are visible cracks, and see whether they can be filled. If your contractor does that type of work too, they might be able to do that at a discount if not at no charge.

    It's good to have waterproofing and drainage--either one alone theoretically is enough but as you are seeing things can go wrong so it's best to do both. The situation now without drainage is a good test of the waterproofing.

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