Thermal bridge: definition how to solve the problem?

Weak links in the insulation of houses, thermal bridges are responsible for the increase in energy expenditure, not to mention the discomfort they generate for the occupants of the place. To remedy this, the installation of an insulating screen is essential.

What is a thermal bridge?

An insulated house does not always mean that it is airtight. It can indeed present heat losses in different places and in a very varied way. Thermal bridges, for example, appear at construction points and appear due to a failure of the insulation or a poorly constructed insulation system. As soon as there is a discontinuity between the structural walls and the materials, this phenomenon is inevitable.
These thermal bridges are located at the junction of the balconies and the walls, between the floors and the walls, between the joinery and the walls or at the junction of the roof and the walls. The openings, especially at the level of windows, doors and loggias, also present thermal bridges.

This phenomenon inevitably leads to the appearance of condensation and humidity which in turn lead to the appearance of halos, the blistering of paintwork and the development of mould. In addition, when the walls cool down, water droplets form and infiltrate the wall coverings, insulation and frames. It can happen that the damage is particularly complicated to repair.

In addition to damaging infrastructure, thermal bridges affect air quality, humidity and ambient temperature due to heat loss. Worse, these losses are the cause of a significant increase in the energy bill. Heat loss forces the heating system to work harder to heat the house properly.

How to remedy the problems of thermal bridges?

Faced with thermal bridge problems, the ideal would be to insulate the walls from the outside and install a suitable ventilation device. Only downside: this work is extensive and requires a very large budget. The simplest and least expensive solution therefore consists in remedying the visible aspect of the problem, which is the proliferation of mould. The idea is to fix an insulating screen to prevent condensation at the level of the cold zones which are flush with the ceiling, at the level of the upper part of the facade walls or of the intermediate floor slabs. Extruded polystyrene panels will be placed at these parts, cornices for example.

Why extruded polystyrene? Quite simply because this material is easier to cut, is easy to paint thanks to its smooth texture, has a flexible character which simplifies installation on irregular supports and only requires an acrylic glue during installation. Before attaching the extruded polystyrene strips, it is important to thoroughly clean the corner of the mold-infested ceiling using 10% concentrated bleach. After cutting the insulation, apply the glue and then start placing it on the wall. Be sure to adjust it correctly to avoid the open spaces against which the fight is precisely waged. Apply filler or mastic between the joints then finish with the paint.

Leave a Comment