A new ASTM International test method aims to prevent air leakage in and around roofs, helping improve energy efficiency, reduce moisture problems, and prevent pollutants from entering the building.
 
“It is critical that each assembly of the building envelope be investigated for air leakage performance with appropriate standards,” says ASTM member Sudhakar Molleti. What cannot be captured in the material and full envelop air leakage testing i.e. the structural strength and continuity of the air barrier assembly can be quantified in the assembly testing. To achieve energy efficiency of building and to adapt for climate change, comprehensive data of material, assembly and full envelope air leakage testing are needed. By quantifying air leakage in roof assemblies, this new standard can serve as a platform for supporting code compliance and for constructing energy efficient and sustainable roof assemblies.”  
 
Molleti, a research officer with over 10 years of roof assembly testing at the National Research Council of Canada, notes that roofing membranes are air impermeable but can be compromised by factors such as lack of continuity of the membrane seams, improper detailing around rooftop preparations, improper selection of flashing materials, and improper connection of roof membranes to the exterior wall barrier.
 
Specifically, this new test method is a laboratory technique to determine air leakage in low-sloped membrane roof assemblies and accounts for the wind fatigue expected during the life span of a roof by simulating negative air pressure differences.
 
The new standard (soon to be published as D8052/D0852M, Test Method for Quantification of Air Leakage in Low Sloped Membrane Roof Assemblies) was developed by ASTM’s committee on roofing and waterproofing (D08).
 
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