Underlay for flooring

Underlay is needed when a floor is laid floating — on its locking system, without bonding it to the substrate. Glue-down floors do not use it: there the adhesive layer holds the covering to the base.

An underlay does three jobs. It damps footfall noise both in the room and in the one below — in apartment buildings that is often the deciding argument. It evens out the small irregularities no screed avoids. And, together with a film, it protects the timber from moisture rising out of a concrete base.

The range covers BOEN Boengard, Maxima Polynorm and Viscoh Air, from €3 to €7/m². They differ in thickness, sound figures and whether a vapour barrier is built in, so compare the actual numbers on the product pages before choosing — particularly with underfloor heating, where low thermal resistance matters. A protective film for covering a finished floor during construction is sold separately.

Choose the decor on the BOEN collections page; for glue-down you will need adhesives and primers.