Blower Door Testing is also known as Air Sealing and Insulation Testing. As of the 2016 NYCECC, the Blower Door Test is now required on all new residential constructions in New York City. As a professional envelope consulting team, our blower door testing services will meet all your project requirements!


For single family houses, a mandatory air leakage test must be conducted to ensure the air leakage rate does not exceed 3 air changes per hour (3 ACH) at 50 Pascals. For buildings that have 2 to 7 dwelling units within the building envelope, and with 8 or more dwelling units within the building envelope, drawings may identify alternate testing procedures of sample “testing unit” verification methods as specified in the code.


For new commercial buildings 25,000 to 49,999 sf in the conditioned space floor area, and 75 ft or less in height, mandatory air leakage testing must be conducted to ensure the air leakage rate does not exceed 0.4 cfm/ft2 of envelope area at 75 Pascals. A detailed testing plan must be created, and a proper testing methodology has to be selected, approved, and implemented by qualified individuals.


For new commercial buildings 50,000 sf or greater in the conditioned space floor area, an Air Barrier Continuity Plan must be prepared and implemented. The Air Barrier Continuity Plan must specify (1) List of typical joint and seam conditions, (2) Testing method options for each, (3) Sampling rates of test, (4) Quality control process in test, and (5) Guidelines for test reports and final certificates.

As a leading provider in the energy engineering industry, our engineers have performed thousands of blower door tests and air sealing work. From 1 to 4 family houses to high rise commercial buildings, our blower door test is COMPREHENSIVE, ACCURATE, and AFFORDABLE.

Most importantly, we never leave our clients alone! Our experts walk customers through the project and share their knowledge to help them achieve the air sealing goals. We customize every project and work closely with our client until the project successfully passes the code requirements!

What is a Blower Door Test?

A “Blower Door” is an amazing diagnostic tool used to measure how much air filters in and out or how airtight a building is.

The blower door allows the tester to apply consistent and measurable pressure to the house by setting up the blower door fan in an exterior door facing outward to depressurize the home.

All the air that the fan blows out of the house is replaced by air coming in through all the leaks in the house, so by measuring the air moving out through the fan, we can tell how much the house leaks at that pressure, which is generally 50 pascals.

Frequently Asked Questions

How long a blower door test takes will vary based on the size of the home. Generally, a blower door test, when combined with a whole home energy audit, should take approximately 1-2 hours. The blower door test itself can run for about a half an hour.

Yes, you can be at home during a blower door test. In fact, you may want to walk around your home with your energy advisor as the test is running; it’s a great way to physically feel the movement in the air and pinpoint exactly where the leakage is coming from.

Passing a blower door test is not necessarily difficult, but it does require proper preparation, attention to detail, and adherence to specific building standards and guidelines. While most contractors aim to succeed in the initial blower door test, it is estimated that around 50% of newly constructed homes will not pass on the first attempt, so don’t feel bad if you don’t get the results you hope for – retesting is common, and it allows you to verify that improvements have been made.

ACH @ 50 pascals: ACH or “Air Changes Per Hour” at 50 pascals measures how many times per hour that the air in your home will be replaced. For example, ACH5@50 means that at a test pressure of 50 pascals, the total volume of air in your home will be replaced 5 times in one hour. More simply, ACH1-ACH5 tell the tester that the home is semi-tight, where ACH5-ACH9 tell the tester it is a moderately leaky home. Anything over ACH9 is a very loose or leaky home. So for this test result, the lower the number, the tighter the house.

CFM @ 50 pascals: CFM or “Cubic Feet Per Minute” at 50 pascals measures how much air is moving from your home through the blower door fan and to the outside. So typically, tight homes will be under 1250 CFM at 50 pascals, moderately leaky homes will be between 1300 and 3000 CFM at 50 pascals and very leaky homes will be any number over 3000 CFM at 50 pascals.