The thermal envelope

It is the container of all the inhabitable interior spaces of a building, including its enclosures, openings and thermal bridges, and separates them from the exterior environment.

The envelope is one of the key elements of the building, which apart from reflecting its identity and the final character must contribute to the fulfillment of a series of normative requirements according to the Technical Building Code; relevant technical aspects that are aimed at contributing to the comfort conditions inside the homes.

Requirements of the Technical Building Code

“The buildings will have an envelope with characteristics such that it adequately limits the energy demand necessary to achieve thermal well-being based on the local climate, the use of the building and the summer and winter regime, as well as its insulation characteristics. and inertia, air permeability and exposure to solar radiation, reducing the risk of surface and interstitial condensation moisture that may impair their characteristics and adequately treating thermal bridges to limit heat losses or gains and avoid hygrothermal problems in the themselves “

First of the CTE measures, within the logical order of carrying out a project is the “Basic Requirement HE 1: Limitation of energy demand”

Thermal bridge, part of the enclosure

The Technical Building Code, in its Basic Document HE, section HE1, defines thermal bridge as that area of ​​the building’s thermal envelope in which a variation in the uniformity of the construction is evidenced, either by a change in the thickness of the enclosure or the materials used, due to the complete or partial penetration of construction elements with different conductivity, due to the difference between the external and internal area of ​​the element, etc., which lead to a reduction in thermal resistance with respect to the rest of the enclosure.

The EN ISO 10211 standard defines thermal bridging as that part of a building envelope where the normally uniform thermal resistance changes significantly due to:

  1. Complete or partial penetrations in the enclosure of a building, of materials with different thermal conductivity

  2. A change in the thickness of the factory

  3. A difference between internal or external areas, such as joints between walls, floors, or ceilings

In short, a thermal bridge is that area of ​​the envelope in which for one reason or another the thermal properties are considerably reduced compared to the rest of the façade. They are mainly pillars and slab fronts.

Thermographies allow us to capture the infrared radiation of the elements, and transform them into a temperature value, this being a very simple method to observe the different behavior of the elements of the envelope.