Trombe Wall

A trombe wall is an internal mass that absorbs heat to be released later inside a home. Southern facing windows allow radiant energy from the sun to heat the wall. The surface of the wall should be painted black or dark gray to maximize the heat absorbed. The opposite side of the wall can be textured with decorative brick, stone or concrete, which will also act as a mass to be heated and release heat.

A trombe wall or internal mass in a floor will need to be supported structurally. Make sure an architect, building contractor or engineer approves the plans for structural support. The trombe wall or mass contained in a floor should not be in contact with an outside wall or foundation—this will lead to heat loss.

Research has found that rocks embedded inside a concrete floor mass will help absorb and release heat at night. The ideal size for the rocks is the same as a potato!