Moisture balance assessment at room scale for four cases based on numerical simulations of heat–air–moisture transfers for a realistic occupancy scenario

Abstract

The moisture balance at room scale is influenced by the air change rate, moisture production and vapour transfer with the envelope. However, results may differ strongly from one study to another depending on the sizing of the ventilation system, the boundary conditions and the modelling of vapour transfer in the walls. This paper aims to provide a realistic comparison of usual construction techniques based on energy consumption, indoor comfort and durability. To achieve this objective, an existing whole-building heat–air–moisture simulation tool was selected to compute coupled transfer at room scale over an entire year. Moisture production due to occupancy was modelled using a stochastic approach. Four cases were selected to emphasize the differences of both a vapour-permeable wall assembly and a relative humidity sensitive ventilation system compared to common practices.

Keywords:

• numerical model
• probabilistic occupancy scenario
• hygroscopic insulation
• relative humidity sensitive ventilation
• indoor comfort
• wooden-frame house

ORCID

Matthieu Labat http://orcid.org/0000-0003-4532-4327