In a renovation of an old home can I use 7/16-inch OSB sub-flooring panels over 1-inch rough pine boards for carpet underlayment?
Yes, you can use OSB, as long as you leave a 1/8” space between panels to allow for adjustments to changing moisture conditions. Ensure that the diagonal board subflooring screwed down to prevent squeaks. Sand any uneven joints or areas and then apply a PL400 sub-floor adhesive to the OSB and screw it to the subflooring. Install the carpet and enjoy!