why install warm board panel over OSB?
We have 2 types of panels. Warmboard-S is a structural subfloor panel that usually goes over joist or often times concrete. These panels are tongue and groove, are 1 1/8″ thick and measure 4′x8′. Warmboard-R, which is made from OSB, is smaller and thinner and usually goes over an existing subfloor in a remodel application. It measures 2′x4′ and it installs over concrete as well. In all likelihood, it is the “R” panel that is getting installed over an OSB subfloor, though we most frequently see plywood subfloors.