Schluter® DITRA-HEAT-DUO ROLL 3'2-5/8" X 33'6-1/2"= 108 SFDITRA HEAT DUO adds a thermal break and sound control layer to the standard DITRA HEAT membrane. Reach for this when the floor is above another living space, over a cold garage, or in a condo where impact noise transmission matters. 5 16" (8mm) thick performs the same four functions as standard DITRA HEAT (uncoupling, waterproofing, vapour management, load distribution) plus integrated sound and thermal insulation 108 sq ft roll at 32 5 8" wide