Joe J wrote:
I'm attaching 2 x 4s to the studs in a finished garage. Finished with
1/2" drywall. Are 3" screws long enough, I have a bunch leftover from a
different project? The 2 x 4s will be holding 5/8 plywood for shelves.
Or, should I just bite the bullet and go with 3 1/2?

Ditch the drywall screws for the purpose entirely.

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