Influence of Membrane on Airflow in Historical Attic Spaces: The First Principles Study Using CFD Models

Abstract

This paper conducts an initial analysis of the impact of a vapour permeable membrane on airflow within triangular attic spaces, resembling the shape and dimensions of medieval sanctuaries found in historical rural churches in our region. The first principles study, using Computational Fluid Dynamics (CFD) based on the simulation models, aims to identify potential challenges and research directions regarding how the application of this membrane may affect the microclimatic conditions in the attic spaces and the durability of the historical timber trusses. One significant outcome of the study reveals that on a simulated extremely hot summer day, the application of the vapour permeable membrane reduced airflow by 10 to 15 per cent, thus affecting the overall microclimate in the attic.