When installing wood underlayments, what precautions should be taken?
Use only the underlayment boards recommended by the flooring manufacturer for the type of flooring being installed. Wood underlayments must be acclimated by placing them in the area where they will be installed for at least 24 hours before they are installed. Panels should be lightly butted and not filled or flashed unless the board manufacturer specifically recommends filling the joints. Differences in thickness of wood panels should be corrected by sanding. If not acclimated, the boards will expand and contract at rates different from the subfloor over which they are installed and this will increase the risk of tunneling and/or ridging. Filling or flashing joints between panels may also increase the tunneling and/or ridging over these joints and especially in conjunction with lack of acclimation.
