Thermal mass describes how materials such as masonry and concrete are able to absorb heat during hot conditions and then release it when it’s cooler, typically at night. This provides inertia against temperature fluctuations within a building and helps lower the risk of overheating (see overheating). Although less common in the UK, thermal mass can also be used in the design of very low energy homes to capture solar gains during the winter months and recycle internal heat from people and appliances, helping reduce heating bills.
The performance benefits that masonry and other materials with thermal mass can offer on a year-round basis are recognised to some extent within the SAP tool used to calculate the energy/carbon performance of homes and demonstrate Part L compliance. Masonry offers a combination of three basic characteristics which are required to provide a useful level of thermal mass:
MPA Masonry is part of the Mineral Products Association, the trade association for the aggregates, asphalt, cement, concrete, dimension stone, lime, mortar and industrial sand industries. www.mineralproducts.org
The Old Rectory, Main Street, Glenfield, Leicestershire LE3 8DG
T: +44 (0) 116 232 5170