Passive house, or passivhaus in German, where the term was coined, is an architectural model that enters into the essence of the project to promote greater energy efficiency in maintaining the temperature of the building. The Passive House Institute states that, when used, these concepts can save 90% on energy expenditure.
Despite the name, this concept is not limited to houses only, it can be incorporated into any construction, such as offices, buildings, malls, etc.
The passive house is an architectural concept that consists mainly of thermal insulation of the building. This insulation prevents the environment from exchanging much heat with the outside, making it much easier to heat a house, even in the harshest winters.
Passive architecture in hot climates
Although the concept emerged in cold regions, it also proved to be very efficient in hot regions, as even when the heat is intense, the passive house remains at a lower temperature and makes cooling resources, such as air conditioning, much more efficient. To use this concept, however, some adaptations need to be made in the project, especially in relation to solar incidence.
The first passive house in Latin America, by the way, was built here in Brazil, in the city of Natal, in 2018.
Some elements are essential for the construction to obtain the name of passive house. Are they:
- Thermal insulation
This is the main point. The insulation used in passive architecture is far superior to that used in traditional civil construction. The materials of all layers are designed to achieve the highest level of insulation.
- Thermal bridges Thermal
bridges are all points of an architectural project where the interior is connected to the exterior, that is, they are places where thermal insulation breaks. In the passive architecture, the aim is to eliminate these points as much as possible.
For example, you will hardly find a passive house with a mailbox built into the door, meaning the mailbox will be disconnected from the main building.
- Doors and windows
Of course, some thermal bridges cannot be eliminated, as is the case with doors and windows. These are the weak points of building a passive house, as heat or cold can be lost through them. Therefore, it is essential that they are built with high quality materials and with their own thermal insulation. In the case of windows, it is recommended that they be double or triple glazed.
- Solar incidence
A passive architecture project is designed to have an optimal absorption of the sun’s rays during the winter and, at the same time, protection from the sun in the summer.
- Mechanical ventilation
In passive house projects it is common to find mechanical ventilation systems, to purify the indoor air and warm the outdoor air before it mixes with the environment. As it is a mechanical ventilation, this process does not consume electricity.
Passive house designs are based on concepts that are applied through the Passive House Planning Package (PHPP) , an Excel model that adapts the characteristics of conventional architecture to passive architecture.