It is similar in principle to that used to characterize building airtightness.

Given its impacts on heat losses, good building airtightness may allow installation of smaller heating and cooling capacities.

Building airtightness levels can be measured by using a fan, temporarily installed in the building envelope (a blower door) to pressurize the building.

In the US, the IECC of 2012 adopted whole building airtightness requirements, including mandatory testing.

Another publication: "Methods and techniques for airtight buildings" was released in 2012, with an overview to the design principles and construction methods for building airtightness.

Building airtightness (also called envelope airtightness) can be defined as the resistance to inward or outward air leakage through unintentional leakage points or areas in the building envelope.

In addition, in May, 2012, USACE issued a new Engineering and Construction Bulletin in collaboration with the Air Barrier Association of America, outlining Army requirements for building airtightness and building air leakage testing for new and renovation construction projects.