Drainage and drying performance of wall assemblies

An industry-sponsored collaborative research project assessing the drainage and drying performance of wall assemblies is now underway with the NRC Institute for Research in Construction (NRC-IRC) and the Air Barrier Association of America (ABAA). The three-year project was outlined at an initial meeting in December. Eight industry partners (see box), representing sheathing membrane, drainage component and cladding interests, took part.

Currently, there is not an agreed-upon method to determine how wall assemblies incorporating a drainage cavity behind the cladding respond to heightened rain loads. This research project aims to assess these wall assemblies with respect to the consequences of water entry behind the cladding and the resulting effects on the moisture sensitive components in the wall.Unique testing and simulation facilities at NRC-IRC are a key to the success of of the project. Results from the research will assist in determining locations across North America where wall systems with drainage components may adequately manage inadvertent water entry behind the cladding.

NRC-IRC is seeking other industry partners. For more information, contact Dr. Michael Lacasse at 613-993-9715 or michael.lacasse@nrc-cnrc.gc.ca.