A proper configuration of the envelope is essential to guarantee the building's energy efficiency, as well as the accomplishment of health standards and comfort. In summer and winter, solving these deficiencies becomes even more important, since the extreme climatic conditions reveal the weaknesses or absences of insulation.
To guarantee comfort inside buildings, the regulation establishes indoor conditions of 23-25°C and 45-60% of relative humidity in summer, and 21-23°C with a relative humidity of 40-50% in winter. Apart from those aspects established in regulations regarding thermal transmittance, airtightness and ventilation must also be taken into account.
An excellent thermal insulation is key to health and comfort
When speaking about energy efficiency in buildings, comfort must be achieved thanks to the features of the building itself: the enclosures, the materials used and the orientation of the building.
The choice of insulation systems is a key point to achieve healthy and sustainable buildings.
Comparison of insulating materials
Comparing the thermal conductivity of the most used materiales in buildings, insulation materials like polyurethane systems are the ones that offer a better insulation thanks to their extremely low levels of conductivity.
|Concrete block||0,35-0,79 W/m·K|
|Expanded polystyrene||0,031-0,050 W/m·K|
|Mineral wool||0,031-0,045 W/m·K|
|Extruded polystyrebe||0,029-0,033 W/m·K|
|Spray foam systems||0,022-0,028 W/m·K|
Although the differences among expanded polystyrene, extruded polystyrene, mineral wool and spray foam systems (polyurethane) are of a few decimals, when seeking to achieve the same thermal conductivity it can represent a difference of several centimetres in thickness.
Insulation and airtightness
In addition to thermal insulation, an efficient building must have an adequate airtightness: if the building is not properly sealed, energy losses will occur, having a direct impact on the users health and comfort.
The problem of radon gas
The insulation of a building's envelope does not only affect interior comfort and energy consumption.
There are also health problems related to the infiltration of unwanted particles into buildings, such as radon gas.
Exposure to radon gas can result in serious health consequences. It is estimated that between 3-14% of cases of lung cancer would be related to inhalation of radon gas, according to the WHO.
To prevent radon gas from contaminating interior spaces, there are two solutions: one is ventilation, and the other the installation of an anti-radon barrier. Several studies have shown that anti-radon barriers are the most effective method to prevent the infiltration of this gas.
Taking into account all the factors previously mentioned: thermal insulation, sealing and protection against radon gas, we can conclude by saying that polyurethane systems contribute to achieve "healthier" buildings.