Successful Implementation of Air Tightness Requirements for Residential Buildings

Increasing the air tightness of homes is a cost-effective way to increase energy efficiency. But, as homes are made tighter attention must be paid to providing ventilation air to maintain a healthy environment and make up air for mechanical exhaust devices to maintain the safe operation of atmospherically vented appliances. In the year 2000 a new Minnesota energy code mandating stringent air tightness, mechanical ventilation, and make up air was successfully enacted. The new energy code has resulted in the construction of very energy efficient homes. Because nearly all homes built to the new code have high efficiency furnaces, they are likely to be much more efficient than would be expected by increasing air tightness alone. Minnesota’s experience has shown that it is possible to implement a code requiring tight construction, as long as provisions are included for ventilation and make up air to avoid the potential harmful affects of depressurization.