I want to install French doors on an opening on the ground floor of my house. This will require building out a small interior wall to frame the doors as the opening is too big at the moment. We have a post-tensioned slab so I understand we’re not supposed to nail base plates to the concrete.

What is the best way to fasten the interior wall to the slab? I’m thinking I will just use some adhesive on the baseplate and then some long construction screws to fasten the new walls to the existing ones at the sides and top.

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1 Answer 1


It sounds like you just need to fill the existing opening that the new doors will not fill. That means the walls are only partitions.
Your plan of adhesive and long screws will work just fine. You do need to isolate the bottom plate from the concrete with tar paper or use PT.

  • Dont think they should be "long" screws. Short nails and adhesive should do. Apr 9, 2023 at 3:11
  • Does the adhesive get you past the "can't have wood in contact with concrete" rule?
    – Huesmann
    Apr 9, 2023 at 15:05
  • If the bottom plate is PT and covered, you are good. Edited the answer...didn't think of it originally, thanks.
    – RMDman
    Apr 9, 2023 at 15:30

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