How much air is too much?

The National Research Council of Canada studies roof system air intrusion


Field observations have identified that air intrusion in mechanically attached roof systems can affect roof system performance. However, the questions of how much air movement occurs and which components provide the required resistance to air movement have never been addressed.

To measure air intrusion in mechanically attached roof systems, an experimental study has begun at the National Research Council (NRC) of Canada as part of its Special Interest Group for Dynamic Evaluation of Roofing Systems (SIGDERS) research.

Defining the terms

Air movement consists of either air intrusion or air leakage.