A blower door test is the only way to determine the air tightness of a home. This is measured in Air Changes Per Hour (ACH), and meeting or exceeding 3 ACH is required for all new construction under 2015 IECC. Here is what the 2015 International Energy Conservation Code states:
R402.4 Air leakage (Mandatory). The building thermal envelope shall be constructed to limit air leakage in accordance with the requirements of Sections R402.4.1 through R402.4.4.
R402.4.1 Building thermal envelope. The building thermal envelope shall comply with Sections R402.4.1.1 and R402.4.1.2. The sealing methods between dissimilar materials shall allow for differential expansion and contraction.
R402.4.1.2 Testing. The building or dwelling unit shall be tested and verified as having an air leakage rate not exceeding five air changes per hour in Climate Zones 1 and 2, and three air changes per hour in Climate Zones 3 through 8. Testing shall be conducted in accordance with ASTM E 779 or ASTM E 1827 and reported at a pressure of 0.2 inch w.g. (50 Pascals). Where required by the code official, testing shall be conducted by an approved third party. A written report of the results of the test shall be signed by the party conducting the test and provided to the code official. Testing shall be performed at any time after creation of all penetrations of the building thermal envelope.
Find the whole code section here.
Reasons for air leakage testing:
- The more air tight a house is, the less energy will be required to heat and cool the home in the long term.
- Identify and repair hidden air leaks that would otherwise not have been found.
- Test and identify which building techniques are more airtight than others.
At Scott Home Inspection, we do not just perform a blower door test on the home. With our extensive knowledge of home systems, we can help you find air leaks, and use our infrared cameras when needed. Don’t let other companies leave you guessing where your air leaks are and delaying your schedule! For a full list of our energy services, click here.