I'm installing 5/8' underlayment over a 1/2" subfloor. I've seen contradicting info on how to orient the underlayment. Some say right angles to the subfloor, but some say right angles to the joists. I cant have it both ways, since my subfloor was installed at right angles to the joists. What to do? My previous underlayment (which I removed) was laid across the joists so unless I can find a compelling reason I guess I'll redo it that way.
Also, I want to use nails. Screws are just plain out of the question, and I dont want the expense of renting or buying staple equipment. But the shortest ring shank underlayment nails are 1 1/4", which means every one will be punching a hole and splintering out the bottom of my subfloor, which is not desirable. I know they make 25 mm (1 inch) underlayment nails but I cant find them in the US (or Canada, so far)..
What to do?