Underlays

Underlays are used to isolate lead sheet from its substrate. They allow expansion and contraction with changes in temperature by reducing drag between the two materials. An effective underlay will also support the lead sheet and level out substrate imperfections such as nail heads or knots. Our underlay additionally protects the lead sheet from condensation and corrosive attack, is free of any substance that can degrade lead and is not adversely affected by in-situ welding.