Ventilation of residential buildings

Ventilation, whether natural or mechanical, is essential for good air quality.

Its priority is to satisfy hygiene and comfort needs.

In particular, it aims to :

• supply fresh air, in particular to avoid confinement and ensure the proper operation of combustion appliances;

• evacuate air contaminated by various pollutants;

• combat humidity and condensation.

While ventilation can also reduce the concentration of certain specific pollutants, by bringing in outside air and evacuating polluted air, it should not be considered sufficient: only by reducing pollutant emissions at source can sustainable action be taken.

General and permanent ventilation has been a legal requirement since 1969 for all dwellings built since that date, whether multi-family or single-family. Ventilation can be either natural, using ducts with natural draught, or through a mechanical ventilation system (VMC).

The decree of October 28, 1983, amending the decree of March 24, 1982, on the ventilation of dwellings, in force for new constructions, has retained the principle of general and permanent ventilation of the decree of October 22, 1969. It sets minimum extracted air flow requirements for service rooms, and authorizes flow modulation.

To take account of the specific features of the French overseas departments, ventilation regulations have been drawn up for new residential buildings in the overseas departments, adapted to local climatic conditions, construction techniques and ventilation practices.

When we breathe, we consume the oxygen in the air and release CO2. Ventilation renews the air inside a building, maintaining oxygen levels and evacuating humidity, excess CO2 and numerous pollutants. A good ventilation system is therefore essential to guarantee the health of occupants and the durability of the building.

Ventilation requirements have evolved over time.

Half the housing stock was built before 1967, i.e. before the regulations on ventilation of dwellings introducing the principle of general and permanent ventilation (decrees of 1969, 1982).

Controlled mechanical ventilation (CMV) and natural ventilation together account for almost 70% of homes.

Dual-flow CMVs account for just 1.1% of the installed base.

Natural ventilation in old and/or renovated homes. Since 1990, natural ventilation has virtually disappeared from new housing construction. It is present in 41% of multi-family dwellings, but only 29% of single-family homes....