Great all-in-one underlayment for moisture protection and sound reduction

Kährs Combo Underlayment is a two-ply polyethylene film with flexible polystyrene granules sandwiched between to provide a dual moisture barrier with a thickness of 3 mm. It has a compression recovery of 80% (ASTM D1055) without loss of resilience. It also has a good sound rating (ASTM E-90 and E-492, STC = 59, IIC = 59) which means it provides very good sound deadening qualities. See Specs in side bar.

Like most good underlayment, Kahrs Combo helps to smooth out any slight imperfections in a concrete or wooden subfloor. A thicker top film layer with an eight-inch overlay flap and a new 'peel and stick' adhesive strip along the length of the roll makes for easy installation. The new material combined with the overlap flap, meets or exceeds all known standards for moisture protection, impact strength, resistance to UV radiation and durability.

Kahrs Combo can be used under any floor made by Kahrs, as well as any floating bamboo or engineered hardwood floor, and is ideal for use over hydronic radiant floor heating systems. It stops moisture but allows heat to pass through easily as it has a very low R-value.