How to Install Foil Underlayment
Whether installing wood or laminate flooring, an underlayment is a critical part of the process. An underlayment is not the same as the subfloor. The subfloor is attached to the joists or beams and provides strength and stability to the floor. Underlayment is a cushion between the subfloor and the underside of the flooring material. It also deadens sound as homeowners walk. Special underlayment materials are available that prevent moisture penetration. Foil underlayment is used to prevent heat gain in the summer and heat loss in the winter.
Clean the subfloor with a broom or vacuum cleaner. The floor should be dry prior to installing the underlayment.
Unroll the underlayment along the longest wall of the room. Cut the underlayment at the wall using the utility knife. Unroll another length of underlayment immediately next to the first piece.
Butt the two pieces together. Apply tape along the entire seam for maximum moisture and heat loss protection. Continue unrolling and taping the underlayment until the entire floor is covered. Install the flooring material according to manufacturer's instructions.