thomas rubino wrote:Yvonne; You will want to support the floor underneath your mass. pier blocks on firm earth (below frost point) 4x4 or better for added support. Depends how stout it is currently built, how much you might need to beef it up. Average weight for a mass is similar to a king size waterbed. Protecting your wooden floors from the heat of the mass is also an important consideration.
thomas rubino wrote:Yvonne; Yes , to keep from trying to heat the earth (can't do it ) you must have some form of insulator below your rmh. Using 4" hard foam is common when pouring concrete. Or a thick cob (perlite , clay and straw ) layer would also work and be cheaper. You want your heat to collect in the mass not under the floor.