Large-Scale Testing of Two Flat Roof Assemblies Insulated with Cellulose
Publication: Journal of Architectural Engineering
Volume 6, Issue 1
Abstract
A laboratory test using a large-scale environmental chamber has been carried out on two flat roof models fully insulated with cellulose fiber. These two models represent the most representative single-cavity flat roofs, built in Montreal between 1930 and 1970, being insulated as part of an energy conservation program. The insulating strategy consists of packing cellulose fiber in the cavity. The goal of the test program was to determine the risk of rotting of the wood structure and moisture accumulation in the roof assembly. The test was performed using real-scale huts that were exposed to 6 months of winter and summer conditions. Two roof assemblies were each divided into five roof cavities. The main variables were the mode of moisture transfer (diffusion only and diffusion combined with air exfiltration), type of vapor barrier, and air leakage paths. The construction of the huts and the monitoring plan are described. The results of the 6-month test program using seven simulated climatic conditions are presented. Wetting and drying curves for different parts of the assemblies as well as the levels of exposure to moisture are presented and analyzed.
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Information & Authors
Information
Published In
Journal of Architectural Engineering
Volume 6 • Issue 1 • March 2000
Pages: 12 - 23
History
Received: Oct 26, 1998
Published online: Mar 1, 2000
Published in print: Mar 2000
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