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What is thermal bridging and overcoming the challenge it presents.

The ever increasing need for compliant non-combustible façade systems on tall buildings raises a number of questions and challenges around materials that are to be specified and used. Not only do specified materials need to be of limited combustibility but also need to prevent heat loss from buildings. Heat can be lost through materials that create thermal bridges across the depth of the outer walls and facades.

Simply put, thermal bridging is the transfer of heat across an object through materials that conduct heat well. The conductive material creates a path of least resistance for the heat. Heat loss or thermal transfer at penetrations to the building façade causes lower temperatures inside the building. Where these temperatures are lower than the dew point of the air surface condensation is caused with moisture droplets forming and pooling. Moisture in these areas can spread and lead to the growth of mould and spores. There is also the obvious result of higher energy consumption and higher heating bills.

masonry support for thermal breaks

How Firma can help with this issue.

FirmaTherm T thermal breaks are offered by Firma as standard shims with our masonry support brackets for use on steel or concrete. The product has very limited combustibility with heat resistance of temperatures up to 10000C. The product has extremely high compressive strength with thermal conductivity as low as 0.3W/m.K. As a comparison, steel has a thermal conductivity of 45W/m.K. Stainless Steel however has a lower thermal conductivity of 15W/m.K, but still requires the use of thermal breaks to minimise heat loss. Publication “SCI P380 ‘Avoidance of Thermal Bridging in Steel Construction” suggests that where masonry support brackets are mounted at spacings of less than 600mm then thermal breaks should be considered to minimise heat loss.

The FirmaTherm T thermal break shims are 3mm thick as standard. These thermal break shims can be combined to increase the thermal transfer resistance. This makes them suitable even for the rigorous thermal conductivity requirements of Passivhaus schemes. Contact Firma to discuss the thermal and non-combustible material requirements of your building scheme for further advice and design assistance…

Thermal breaks

Non combustible façade systems - Call 01603 722 330