Building Paper Between Layers of Flooring

Hardwood Floors

• With most flooring installations, some type of underlayment is required on top of the subfloor, but with newer homes, where exterior grade plywood is used as a subfloor, there are exceptions to the rule, such as with hardwood and engineered wood. In these cases, a simple layer of building paper between the subfloor and the finish floor is sufficient to provide a moisture barrier between the two levels and protect the finish floor. However, the building paper for hardwood floor use needs to be impermeable enough to provide moisture protection. Always check with your hardwood manufacturer for recommended types.

Laminate Flooring

• Building paper is used with laminate flooring the same way hardwood floors utilize it, but the difference is that laminate floors are far more resistant to moisture. Thus, building paper is an “extra” layer that goes above and beyond the padding installed with many laminates. However, this only applies to floating formats of laminate floors. Those laminates that are peel-and-stick or glued-down applications cannot utilize building paper between the subfloor and the finish layer.

Mud Floats

• For tile and natural stone installations, building paper is most commonly used when creating a mud-floated underlayment for the tile installation. A mud float is the old-fashioned way of creating an underlayment, and was the predecessor to concrete boards that are now more commonly used. A layer of building paper is applied on top of the subfloor, followed by a layer of chicken wire, both of which are nailed down to the subfloor. On top of that a 1 1/2- to 3-inch-thick layer of concrete is packed and smoothed down, and allowed to harden to provide a base for the tile.

General Use

• There are different types of building paper, with the most common being a resin-based or tar-based paper. It also can be used as padding material for building up low spots in a floor so the finish hardwood floor or laminate surface is flat. In addition, it can be doubled and triple folded to create small shims useful for bringing low sections of hardwood floor up to height, or to help hide imperfections in the wood itself where pieces are thinner. These shims and buffer layers are under the hardwood but on top of the subfloor and any existing layers of building paper already in place as a moisture barrier.