Thermal mass

Thermal mass

Materials with high thermal mass (materials that are good at absorbing and storing heat) can be used to aid heating in winter and cooling in summer. These materials are usually heavy - such as concrete and brick - and are used in floors or walls.

Used properly - the right amount in the right place, with proper insulation - will ensure they help passive cooling by absorbing heat from the surrounding air. They will keep absorbing heat as long as the air temperature is higher than the temperature of the thermal mass.

Thermal mass designed to get direct sun in winter, but not in summer, will stay cool during summer days and keep air temperatures down.

See Using thermal mass for heating and cooling for more information.