Theoretical basis for assessment of air quality and heat losses for domestic ventilation systems in France.

Ventilation of buildings is necessary, both to insure adequate indoor air quality and to protect the building itself against condensation and mould growth. On the other hand, ventilation rates must not lead to excessive energy consumption. French regulation doesn't appreciate directly the indoor air quality but fixes requirements for the value of exhaust stale air in service rooms ; furthermore heat losses related to cross ventilation due to wind effects are also taken into account. For assessment of Demand Control Ventilation systems both air quality and heat losses have to be compared to a mechanical exhaust only system. In this paper, we describe the methodology and the CSTB computer models, and how they have been used to design the French rules related to the energy demand of ventilation systems and the air quality level obtained with DCV systems by reference to a conventional mechanical ventilation system.