Thermal Bridging:
What It Is and How to Avoid It

Thermal bridges are places in a building where heat can transfer between the exterior and interior of the building via Conduction, Convection or Radiation.

They are one of the most significant sources of heat loss within a building. A conductive material or a gap in the insulation can form a ‘Bridge’ between the inside of a home and the exterior where heat can escape. This can lead to cold spots, condensation and even mould appearing.

The design and construction of a new building should try to have as few thermal bridges as possible and create a consistent ‘U-Value’ across the whole area.

There are two main types of thermal bridging:

1. Repeating Thermal Bridge

An example is when wall ties regularly bridge the cavity in a wall and therefore create a thermal bridge between the insulation.

2. Non-Repeating Thermal Bridge

An example is at junctions between construction elements – where a wall meets the floor or where the roof or windows meet walls.

Thermal bridges will be more common in older, poorly constructed, single skin buildings. They can still occur in modern builds if workmanship or the design is poor.

However, modern building regulations state that:

‘The building fabric should be constructed so that there are no reasonably avoidable thermal bridges in the insulation layers caused by gaps within the various elements, at the joints between elements and at the edges of elements such as those around window and door openings.’

This should result in both architects and builders looking carefully at reducing the opportunity for thermal bridging to occur in new build properties.

For further information, please contact Ed or Kelly on 01284 365345 or email ed@granitebw.co.uk / kelly@granitebw.co.uk.