Roofing Researchers to Develop New Test Protocol for Quantifying Air Leakage Through Low-Slope Assem
Roofing Researchers to Develop New Test
Protocol for Quantifying Air Leakage Through Low-Slope Assemblies
Increasing demand for and the rising cost
of energy have intensified interest in the issue of air leakage through the
building envelope. However, until recently, the roof – in contrast to walls and
windows – has not received much attention regarding its air-leakage
performance.
Being able to control air intrusion is
critical in roofing design, as this has several effects on the performance of
the roof – on wind uplift, energy consumption and moisture migration. Now,
advances in roofing technology are providing greater opportunities to control
air intrusion. But at present, there are no code requirements, standard
specifications or test methods for the design or quantification of air-barrier
performance in roofing assemblies.
NRC-IRC researchers are working to address
these deficiencies. They have laid the groundwork by conducting a feasibility
study, which included the creation of a small-scale test facility, and
attempted to quantify the air-leakage rate of the roofing assembly both with
and without an air barrier.
The preliminary results clearly
demonstrated the significance of the barrier in providing air-leakage
resistance. But because these observations were based on small-scale
experiments, which were devoid of any joints, junctures or penetrations, it is
clear that there is a need to build a full-scale air-leakage facility that
replicates a real roof so that further research can be conducted.
NRC-IRC is seeking collaborators from both
private and public sectors for this study to develop:
A laboratory test protocol to quantify air leakage in roofs
that could be used in the development of codes, standards and guidelines;
Design tools for air barrier systems in roofs;
A field test protocol that provides comparable results to those
of the laboratory test protocol;
An analytical tool to predict changes in energy demand due to
variations in the air-leakage characteristics of roof assemblies.
Specific questions can be directed to Dr.
Sudhakar Molleti at (613) 993-9373, Fax: (613) 998-6802, or e-mail:
.
