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Materials & Specificationsaka: roofing feltaka: synthetic underlaymentaka: floor underlayment

Underlayment

In Plain English

A layer of material installed between the structural surface and the finish material for protection or smoothness.

Definition

Underlayment is a material installed between a substrate and a finish material to provide a smooth surface, additional moisture protection, sound reduction, or cushioning. Roofing underlayment (felt or synthetic) is installed over roof sheathing before finish roofing. Flooring underlayment is installed under carpet, laminate, or hardwood flooring.

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