CH-89-09-3 -- Canadian Research into the Installed Performance of Kitchen Exhaust Fans PDF

The 1985 National Building Code of Canada specifies that new houses must have an installed exhaust capacity of at least 0.5 air changes per hour. However, field testing has shown that the performance of installed exhaust equipment is highly variable, and that household usage of exhaust fans is unpredictable. How are builders to meet the code specification and maintain acceptable airflow and sound levels?

A government research project was designed to give builders a clear guide to the selection and installation of household exhaust fans. This paper will be restricted to the results for kitchen range hoods. The contractor investigated existing literature and equipmento establish household usage patterns, the performance of fans and exhaust system components, and the potential for new products and systems. Field inspections on 20 houses across Canada showed how the fans were installed and by whom. Field testing revealed the deviation of these fans from rated flow levels. Simultaneous laboratory testing helped to explain why the systems failed to meet rated capacity.

The end product is a builder’s guide to exhaust fans. The most succinct recommendations are to avoid using the cheapest products and to install to the manufacturer’s specifications.