Hello good folks.

I took my bathroom down to the original 1X subfloor installed diagonally. Did not replace them as they were going under the walls and still were good. Went over top of that with LP products TopNotch 350 3/4 T&G OSB (similar to Advantech OSB I was told).

Next I'm going to go over that with 1/4 plywood underlayment for the sheet vinyl. I've seen staples are the most suggested choice for installation, but what length is suggested? Do I want it to go only into the osb, or go through the osb and into the first layer 1X boards? What about staple crown size

Scott

 

To secure the 1/4" plywood, you can use 7/8" narrow crown (7/32") staples and have good holding.