What Is Blower Door Testing – IECC 2015 Requirements:

Date Published: February 25, 2017

With the 2015 International Energy Conservation Code (IECC), blower door testing is now a mandatory requirement on all new construction for residential homes. So what is blower door testing?

What is blower door testing?

A blower door test is performed to measure the exact air-tightness of a home.  Beginning with the 2012-IECC, a maximum air leakage rate is defined and each new home must meet this tightness level verified with a blower door test.

How does it work?

A blower door consists of a frame and flexible panel that fit into an exterior doorway. A powerful, variable-speed fan mounts into the frame. The fan blows air out of the house, lowering the inside air pressure. The higher outside air pressure then flows in through all unsealed cracks and openings.   An integrated pressure gauge measures the pressure differences between the inside and outside the home, and an airflow manometer and hoses are utilized for measuring airflow. The equipment used in the blower door test determines a home’s air infiltration rate in air changes per hour (ACH). Find out about more common leaks found during a blower door test here.

Do you need a blower door test performed on your project fast? We can help. Visit our blower door service page to learn more and schedule now.

When do you perform a blower door test?

Blower door testing is typically performed at the end of construction, once the house is completely dried in, all penetrations sealed, and lighting trim kits installed.  Basically, anything that would allow an unwanted air leak needs to be sealed.

Who can do the testing?

Scott Home Inspection can perform blower door testing. The company also performs duct leakage testing, as well as full energy rating services including RES-Check reports and HERS ratings.

Is this required in the county you are building in?

Most of the counties along the Front Range of Colorado have moved to at least the 2012 building code by this time. However, the Colorado energy office published this helpful map to show which counties are on 2012 or 2015.

Let our local team of Certified HERS Raters, Certified Rating Field Inspectors and Certified ASHI Home Inspectors work with you to help you meet the IECC energy code requirements of the various municipalities along the Front Range. We can assist your team in determining the best options for the design and construction of your project. Our energy rating services are performed professionally with a focus on accuracy and responsive support.  We are your go-to one-stop-shop” offering Energy Rating Services for Architects, Builders, Contractors, HVAC Professionals, and Homeowners.

For more information visit the Blower Door and Air Leakage page on our website.

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About the Author: George Scott

George founded Scott Home Inspection in 2006, and has grown the business into a multi-inspector firm serving the Colorado Front Range, from Fort Collins down to Colorado Springs. As an ASHI Certified Home Inspector and Certified Energy Rater, George is an excellent resource to help with inspection and energy-related requirements.

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  1. brennerbuilders@outlook.com'
    Brian Brenner March 1, 2017 at 8:02 am

    Hi George, Can a home be too tight and need to have a system installed that mechanically brings in fresh conditioned air to the home.
    What are the passing and failing pressure ratings for new homes? Is it also based on square footage of the home?

    • George Scott March 1, 2017 at 8:18 am

      The IECC code establishes maximum air leakage rates in a home. In Colorado with the 2012 and 2015 IECC that level is 3 air changes per hour when depressurized to 50 pascals. So the blower door runs, depressurizes the home to 50 PA, then we calculate the air changes based upon the volume of the home. At 3 ACH, this is a very tight home, so you definitely then need to have a mechanical ventilation system to bring in fresh air exchanges. The 2012 and 2015 building code requires a mechanical ventilation system when the home is sealed to this air tightness, so plan on installing an HRV or ERV. When we do blower door testing, we help you to find leaks if the home doesn’t pass, we won’t just leave and not help. We’ll use an IR camera to help find the leakage areas so you know what to seal.

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