Numerical evaluation of the airtightness impact on energy needs in mechanically ventilated dwellings

With the increasing need for higher energy efficiency in buildings, airtightness and ventilation systems choice become major performance issues in well insulated buildings. Buildings energy requirements lead to adapt ventilation strategies in order to reduce energy losses through mechanical balanced or extract ventilation. With the new French thermal regulation, the use of energy-efficient ventilation systems is implicitly required; low air infiltration is explicitly required in residential buildings through minimum airtightness levels.

Estimates of Uncertainty in Multi-Zone Air Leakage Measurements

Although standards for single-zone air leakage tests are widely used, there are no existing standards for several multi-zone cases including: 1) testing air leakage between adjacent zones or 2) testing leakage to the outside from a single unit in a multi-zone building. While a range of test procedures have been used to determine inter-zone leakage using fan-pressurization, the accuracy of the methods can vary significantly. Using field measurements and simulations, we compared the uncertainty in the leakage between two adjacent zones for different measurement and calculation methods.