Best approach for squeaky subfloor fix, with some water stains

subfloor

We are replacing the carpet in our kids room and want to tackle the subfloor as it squeaks. There are two questions I have:

1 We plan on screwing down the existing subfloor, do I need to remove any of the nails in the subfloor? Someone I know did this but a contractor said it was overkill.

2 There are what look like dry water spots in some corners, near the exterior wall. Do I need to be concerned about these? We are having the siding on the outside of that wall replaced soon, so if there is a leak I assume this will be fixed then.

Some photos at https://goo.gl/photos/RH3CpsbfD24xY62V7

Best Answer

When I redo flooring, I always remove all the nails, and then screw the subfloor down. It costs nothing but time, and I'd rather waste time doing it, than have a squeaky nail after the flooring is on.

As for the water marks. It does look like there was some water infiltration, but without poking around it's difficult to say to what extent. Replacing the siding could well solve the issue, depending on where the water came (is coming) from.

If there were animals in the house, the "water" stains could be from poorly housebroken animals. If you notice an odor, you might want to paint the subfloor with some Kilz or similar primer. If it's really stinky, you might want to treat the stains with an enzyme type cleaner before priming.