Do I need to replace subfloor when installing new hardwood?

Question

I bought a 50+ year old house and have decided to replace the hardwood floors. The subfloors are really squeeky, the hardwoods are separating in places and there are large gouges in spots. I plan on tearing up the old floors and wonder what to do with the existing tongue-and-groove subfloors. Should i tear the subfloor up and replace it with new exterior-grade plywood screwed and glued with Liquid Nails for subflooring? Or should I just try screwing the tongue-and-groove subfloor down and install right over it? Any other suggestions?

Answer 1

My house is 50+ years old also. I have replaced most of the sub floor, (not placing new over old, but ripping it out to the frame), The sub floor I haven't replaced, I got rid of the squeaks by :
1. Nail the loose parts down.
2. Put a bunch of wax on the rubbing parts
3. Reinforce the loose parts that don't have a joist from the underside,

Best of luck! I think these fixes will out last me. They work.

Answer 2

Replacing your sub-flooring is a major undertaking since the sub-flooring was installed prior to the interior and exterior walls being raised into place. I suppose anything is possible but I don't believe that it is practical. Personally, I'd lean toward removing the hardwood floors and repairing the existing subfloor as best I could with adhesive and construction screws. Then I'd install an overlayment of felt and plywood and adhere with construction screws, then the new flooring. Good luck!

Answer 3

Replace Subfloor

Answer 4

I would leave the subfloor if its solid, screw it down good to the joists, then I would put down a layer of 15 # felt paper (tar paper) . before reinstalling the hardwood. The felt paper will prevent squeaks between the new hardwood and old subfloor.

Answer 5

Do you have to??? Maybe and maybe not. But if I'm going to put in good new flooring then I'm putting in a new sbu floor and screw it down and glue it.

That way you know you are going to get another fifty years out of it, and after 50 years you probably won't care. Good luck on the flooring.

Answer 6

i have installed several hardwood foors and I'd say as long as the sub floor is good and flat i'd just leave it . I would screw the old floor down though with some good long deck screws.

Answer 7

I would install the new plywood subfloor over your tongue & grove subfloor if it's not terribley warped or unlevel.

Answer 8

i would just screw the old one down if it level, that's the cheapest and best way, but the screws must be counter sunk a little