We offer energy-saving blower door tests and duct leakage tests for compliance with Washington State’s required Air Leakage Testing (R402.4.1.2)

Blower Door Testing NW provides independent, third-party air leakage and duct leakage inspections for new and existing homes. We work with Western Washington builders and homeowners from Olympia to Bellingham (including Tacoma, Seattle, Bellevue, Kirkland, Everett and surrounding areas).


Don’t miss your closing date due to a failed blower door test! We offer pre-test consultation to help you address and identify the areas that can lead to test failure. Correcting these items before sheet rock can help to avoid costly repairs once the house is in the finished stage and ready for final inspection.

Basic Blower Door Testing

We perform blower door leakage tests for single and multi family buildings. We have BPI certified technicians who will not only provide the test results and post the required certificate but also document the findings in the event that the test does not pass. This saves you time and money by making it easier to identify and remedy the areas which are causing the failure.

Duct Leakage Testing

In addition to blower door tests, we offer high-quality inspections for ductwork for homes with forced air or air conditioning. For duct tests, our technicians seal off and depressurize the ventilation system. Then with specialized equipment, they determine how much air pressure is escaping. These duct leakage tests ensure that your system is properly sealed and energy efficient.

We will review your blueprints, measure the house for accurate square footage and volume and provide a complete test certificate including R Values, fuel source and efficiency rating for Heating, Cooling and Domestic Hot Water and of course the Building Air Leakage test results. We will post the required 2012 WSEC Residential Energy Compliance Certificate on or near the electrical panel as required by code.

To schedule your blower door test or pre-consultation, call us at 425-312-3914.

Why use Blower Door Testing NW?

  • BDT-NW uses the best and most updated equipment.
  • BDT-NW offers Blower Door Tests, Duct Leakage Tests, and Pre-Consultation Services.
  • BDT-NW offers 48hr scheduling.
  • BDT-NW is a great choice for an independent 3rd party test (which can be required).
  • Pricing can vary depending on square footage, number of units, and location — please call 425-312-3914 for quote.
Frequently Asked Questions

What is a Duct Leakage Test?

Duct leakage testing is a systematic way to test the energy efficiency of ductwork within homes. By sealing off and depressurizing the ductwork the technician uses specialized equipment to measure the airflow through the system.

What is a Blower Door Test?

Blower door testing is a scientific way to test the air leakage of any given structure. By depressurizing the building and measuring the rate at which air infiltrates the building envelope through any number of imperfections in the structure.

Is it required?

Per R402.4.1.2, this test is required to be done on every new construction home, additions over 500sf and all multi family buildings. As of July 1st 2016 the standard has been set to less than 5 ACH @50 pascals (air exchanges per hour). Your project must meet this standard.

What is Washington R402.4.1.2?

The building or dwelling unit shall be tested and verified as having an air leakage rate of not exceeding 5 air changes per hour. Testing shall be conducted with a blower door at a pressure of 0.2 inches 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. Once visual inspection has confirmed sealing (see Table R402.4.1.1), operable windows and doors manufactured by small business shall be permitted to be sealed off at the frame prior to the test.