Improvement of airtightness in four schools.

Air leakage tests (using the fan pressurisation method) were conducted on four schools, before and after they were retrofitted, in order to determine the effectiveness of various measures for reducing leakage. Caulking wall joints will generally reduce air leakage and is worthwhile if the joints are accessible. Replacing leaky windows will also improve airtightness but may not be cost effective. Routine inspection of outside dampers of the air handling system can help ensure continued airtightness of schools.