Blower Door Tests: What Are They and How Can They Help?

Published on November 12, 2018

A blower door test is an evaluation of the overall airtightness within a residential home or building. They are conducted by an experienced and Registered Energy Advisor, who has specific training to use the unique tools within the test. This allows them to effectively identify and locate all possible air leaks within the building.

As improving air tightness is the most effective home renovation strategy to help you improve your home’s energy efficiency as well as its air quality, we recommend for you to consider conducting a blower door test both before and after any home renovations. This not only makes you applicable for home reno rebates from Union Gas, it also helps to improve the energy efficiency, comfort, and moisture control of your home by a significant amount.

For new homes being built, conducting a blower door test during the construction process is also extremely beneficial, as it provides a concrete result which speaks to the current air tightness of the project. This makes it useful for load and energy calculations done by a mechanical designer. These benefits can allow for changes to be made during the construction process, saving you money as well as ensuring that the home is on track to having the proper amount of energy efficiency once construction is completed.

How Does a Blower Door Test Work?

A residential blower door test involves the placement and sealing of a large fan into the front doorway of a home. After being properly installed and completely sealed, the fan is turned on to blow air out of the house, creating a negative pressure within the interior. This means that any leaks or improperly sealed holes will pull outside air inwards, making the locations easy to detect for our Registered Energy Advisors. Able to utilize various methods to find air leaks, our Registered Energy Advisors are trained to use thermal imaging technology, allowing them to determine changes in air temperature - pointing out locations of unwanted air exchange.

What Information Does a Blower Door Test Provide?

A blower door test provides more than just an insight into the air sealing and energy efficiency of a home or building. It can also show what paths can be taken to improve moisture control and general air circulation.

You will receive the results of your residential blower door test with a number regarding the Air Changes per Hour (ACH) in your home. This number represents how many times all of the air within your home is exchanged over the period of an hour. This provides you and our Registered Energy Advisors with an accurate indication of the level of air sealing within your home; with a high number of Air Changes per Hour being detrimental to energy efficiency. Additionally, as the results of a blower door test can be a bit confusing at first, our Registered Energy Advisors are happy to go over the results with you, and to help you choose which home renovation or retrofit options will the be most cost effective for improving energy efficiency.

Air Tightness and Energy Efficiency Go Hand in Hand

It costs money and takes energy to heat or cool a home. Allowing that air to be freely exchanged with the outside air can not only make your HVAC system work harder, it can also reduce your interior comfort levels. When drafts or unnoticeable air currents find their way into your home, moisture, allergens, and dust are often tagging along as well.

A properly air sealed home that is built today has about 2 Air Changes per Hour at the standard level of pressure (50 pascals). This number can be used as a benchmark for home renovations, with retrofits aiming to reach or surpass this number.

Less energy is needed in order to heat or cool a home that has been properly air sealed. This means that you will see lower utility bills all year long if you decide to improve your home’s air sealing. A lower amount of air leakage can also lower the operational stress of your HVAC system, as it does not need to run as often to keep the house a comfortable temperature. Having formidable air tightness and energy efficiency is an attractive selling point for potential buyers and can work to increase your home’s value.

With over three decades of experience, BSG is proud to be your home renovation experts. With extensive training and on the job experience, our Registered Energy Advisors are well equipped to handle all of your efficiency questions, and to help you improve the comfort your home. Contact us now to set up an appointment for a blower door test - it may be the best investment in your home you will ever make!