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Community and Q&A

Slab-to-Wall Sealant or Caulk

Bruce_Davis | Posted in General Questions on

Need to seal gap between basement concrete slab & concrete wall for radon remediation.  Any particular recommendation on sealer/caulk for this purpose?  Thanks.

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  1. user-2310254 | | #1

    There are variety of caulks made for sealing cracks and gaps in concrete. Polyurethane formulations probably will be more durable than latex. If you have wide or deep cracks, installing backer rod is a good idea.

  2. Expert Member
    BILL WICHERS | | #2

    +1 for polyurethane sealants. You do need to carefully clean the surface first to make sure the sealant will adhere well. Get any dust or mildew crud off before sealing. Small wire brushes work great for this purpose on concrete.


  3. Bruce_Davis | | #3

    I see tubes for about $9-10. Interestingly, my builder had a sub use a two-part polyurethane mix caulk around the perimeter of the house. Most of it cracked & peeled in a year or two. Think it was $2/ft. He also used it on the garage saw cuts. They were then covered with a garage floor coating, so don't know the current caulk condition, but no problems apparent. Thanks.

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