Solid Hardwood, Engineered and Laminate Flooring - subfloors and nails

I finally had the nerve to pull up my carpet and the particle board under it in one room so that I can install hardwood floors.

The particle board had 1/2" plywood (32/16) under it. As I have been previously advised in this forum, I intend to glue and then nail and screw another layer of 1/2" plywood onto the existing plywood before installing 3/4" hardwood floors.

I have now realized that I can rip the particle board up with a wrecker bar, and the board comes up much more quickly. I just need a bigger wrecker bar to save my back. This, however, does leave the nails sticking up out of the plywood.

This is no big problem. I simply pull the nails up. My question is this. Should I be pulling the nails up or hammering them down into the plywood. Or does it matter?

This may be a silly question but I was really surprised at the large number of nails that I have pulled out of the floor so far. I have been afraid that I was going to weaken my subfloor or the joists in some way by literally pulling out hundreds of nails, and then later by nailing another layer of plywood, etc.

So far, I have pulled up almost all of the particle board in one room, and the floor does not feel as stable as before, but I guess this is reasonable considering that a layer of support is now missing (the particle board).

O.K. So I'm paranoid that my house is going to fall down before I'm through. I would never have attempted to do any of this, but my wife thinks we should be able to do it. She is usually right.

Thanks as always for any advice that you can give me. I'm very inexperience in when it comes to do-it-yourself projects.

Thanks agian.

jdi

jingram105,
"Should I be pulling the nails up or hammering them down into the plywood. Or does it matter?"

It really doesn't matter. I would probably pull most of them up, cuz I wouldn't want to be driving screws on top of nail heads. I say screws because there will be less of a problem of future floor squeaks with screws.
fred

Thanks. Appreciate the advice.

jdi

Jd:

Use decking screws to fasten the new plywood and some construction adhesive. Also for a much stronger overall subfloor run the ply the opposite direction of the old and overlap the seams as much as possible.

Good Luck;)