Blower door tests are an accurate and scientific way of demonstrating where a building has air leakage or infiltration. Air flow through a building can have a powerful impact on comfort, expense, and air quality. Nu-Wool uses blower doors as a diagnostic tool to quantify air flow and the resulting heat loss, along with a way to pinpoint specific leaks. The benefits of using blower door testing have been understood and documented enough that most professionals now consider them essential for effective (and cost-effective) air sealing.