Thermal bridge: what is it?

Located at the junction of the constructive elements, a thermal bridge is a defect ofinsulation in the envelope of a construction. Responsible for 5% of thermal losses in a house, the presence of thermal bridges is the cause of some humidity problems by creating cold spots.

Two types of thermal bridge identified

In the new as in renovation, a thermal bridge has its origin in a faulty implementation, a degradation or the absence of insulation or in the poor quality of the materials and equipment used. Thermal bridges are listed in two categories.

Structural or bonding thermal bridge

The most frequently encountered case, this category of thermal bridge is located at the link between:

• low floor and exterior walls;
• the intermediate floor and exterior walls;
• high floor and exterior walls;
• the exterior joinery (window, bay, door) and the exterior wall.

Point thermal bridge

This type of thermal bridge appears when the insulating lining is crossed by an element such as an ankle for example.

Treating thermal bridges in new buildings

In construction new, the presence of thermal bridges can be easily eliminated. From the design stage, heavy materials with good inertia, to reduce the surface losses as much as possible. In the case of floors, integrating thermal breakers ensures the continuity of insulation.

Insulate thermal bridges in the old

In old buildings, dealing with the presence of thermal bridges is more difficult. It is above all necessary to identify them in order to be able to treat them effectively. Calling on an insulation professional allows you to establish a diagnostic and choose the best solution. Depending on the case, the insulation can be done from the inside (ITI) or from the outside (ITE). A very effective solution, the cost of which can be partly absorbed thanks to financial aid such as MaPrim’Rénov, the zero rate eco loan, Coup de Pouce energy, Live better serenity …