GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

Details for bottom plate to slab

thegiz | Posted in General Questions on

Hope everyone enjoys the memorial day weekend. I’m framing tomorrow in a basement and want to double check the details. I’m attaching PT 2×4 to slab for bottom plate. I saw something called FoamSealR at the box store.

Do I place this underneath the PT bottom plate for extra protection and against foundation walls that come in contact to PT wood? Before tapconning my bottom plate in, do I use construction adhesive to attach bottom plate to concrete or does the adhesive cause mold and rot underneath the bottom plate? How are you suppose to attach the sill gasket to wood or concrete?

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.


  1. Expert Member
    PETER G ENGLE PE | | #1

    You can use sill sealer as a capillary break between the concrete/masonry and the PT wood. It is not required but it will help to reduce wicking from minor water events. Cheap insurance. You don't need any construction adhesive or other products under the sill plate, and you don't need to fasten the gasket in place. The tapcons and the weight of the wall will hold it in place once you're done. Drill pilot holes in the sill plate, use them to transfer the Tapcon holes to the slab, lay the gasket in place and poke the Tapcons right through the gasket while installing.

  2. Expert Member


    The sill-seal is there to stop moisture moving through capillary action up into the plate and framing above. You staple the sill-seal to the underside of the plate. There is no point in using adhesive if you are using sill-seal.

Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |