There’s a new condo being built in a nearby northern Californian city and I noticed sets of nail strips above and below each window opening, over the plywood but under the vapor wrap.

What is the purpose of the nail strips? Do they add structural strength? Are they an earthquake code requirement? or are they part of the moisture mitigation system?

nail strips Ps apologies if I’m using the wrong terminology. I’m referring to the horizontal metal strips that are nailed above and below each window visible in the photo above.

1 Answer 1


It’s a structural tie for lateral forces. Those are shear walls and when you cut a window into it, you need to add a tie to “transfer” the load through the wall.

  • Are they an earthquake code requirement or are they found all across the USA?
    – RoboKaren
    Oct 13, 2018 at 17:29
  • 1
    @RoboKaren They are structural ties. They’re used for “high stress conditions” for LATERAL LOADS like in earthquake areas and high wind areas. Yes, they are found all across the U.S.
    – Lee Sam
    Oct 13, 2018 at 19:21

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.