Plywood Floor Underlayment: Multiply Floor Underlayment (Birch): Product Guide

Floor Underlayment Thickness

1/4" Floor Underlayment Multiply 1/4" floor underlayment meets the APA standard for 1/4 inch plywood the minimum recommended thickness, as well as the standards of all major vinyl brands. Multiply 1/4" floor underlayment is composed of 5 plies, which make it an even sturdier alternative to standard 3 ply floor underlayment. It also provides additional strength over all 5.2 mm and 5.5 mm plywood products. Use for sheet vinyl, vinyl tile, rubber tile, and carpet installations over suspended wood-based subfloors. Not recommended for ceramic tile installations; use 3/8" floor underlayment in these situations. 1/4" floor underlayment is available in 4x4, 4x5 and 4x8.
3/8" Floor Underlayment Multiply 3/8" floor underlayment meets the APA standard for 3/8 inch plywood and meets the performance requirements of the Tile Council of America for installation under ceramic tile. It is 50% thicker than 1/4" plywood floor underlayment, and is composed of 7 plies, forming a construction strong enough to provide a safe and solid foundation for ceramic tile over L/360 subflooring. 3/8" floor underlayment may be used under hardwood and laminate flooring, and under resilient floors when installing over existing cushion vinyl, to improve the stiffness of the subfloor or to compensate for the removal of a thick previous floor. 3/8" floor underlayment is available in 4x4, 4x5 and 4x8.