I have leveled out the subfloor with 30pound felt and put down 1/4" B/C plywood for underlyament. So far I have hand nailed 2 1/2 inch ring shank nails on the joists at 4-5" intervals to attach the underlayment to the subfloor/joists. Now I have to nail around the perimeter and also make the grid pattern. I don't want to do this by hand.

I do not have a medium crown stapler, but I do have a Hitachi gun that will shoot shorter ring shanks -- http://www.toolbarn.com/cgi-bin/bigimage.cgi/12302/ I don't want to shoot longer ones since it will result in a bed of exposed nails in the crawl space. Shorter 1 1/4" ring shank nails seem as if they would do the job since the plywood is 1/4, there is some felt, and then the subfloor is 3.4".

Is there any compromise in nailing the perimeter and the grid pattern with the shorter ring shank nails? I will buy the medium crown stapler if I have too, but if the ring shanks will work then that is a savings.

Thanks

I use short galv. ring shank nails all the time for attaching underlayment. Don't use the ones with the plastic tabs though, just the normal round head type.

How close is the spacing when you use ring shank nails? Would you consider using a 16 gauge stapler on 1/4 inch plywood or would that make this thickness of plywood dimple?

You have all you need. I pity the fool who has to take up your underlayment job. heehee I would not sweat the dimple thing. A more likely problem will be the occasional staple blowup when it hits one of your ring shanks.

CHU

p.s. The type of fastener does nothing to affect the required spacing. I would go on a 6in grid and every 4 around the perimeter. Were I not about to shoot 10,000 staples clean through the whole deal, I might use more.

Waitaminit, what is going over this?

Chuck, 1/2" engineered .... there is 3/4 OSB subfloor. I have nailed the snot out of it so far and I would not even want to think about taking it up as it is. I have several more rooms to do and I am not anxious to swing the hammer that many times ... I would like to use a 15 gauge stapler sincem but a friend suggested this might dimple the 1/4 plywood.