An underlayment is a thin layer of material sandwiched between two other materials.
How to fix a low spot in a wood floor.
It s used to help insulate absorb sound and reduce wear on your floor.
This requires using a laser level to pinpoint the low areas and attaching the shims working on bare joists above a basement or crawlspace by gluing and screwing them to the joists.
Water based urethane will dry clear while oil based formulations will impart a slight golden.
If your floor is natural unstained wood then try a few types of floor urethane on your test patch.
Set the front end of the saw s flat blade plate on the damaged board with the blade held up off the surface and pointing in the same direction as the length of the floorboard.
Start the saw and lower the blade into the wood.
If you need to bring down your subfloor you can try either a hand plane or a power sander.
Run it forward along the length of the board making sure not to let it cut into the edges.
High spots and bumps in subfloor.