A blower door test reveals the airtightness of a home.
What is a blower door test?
A blower door test determines how much outside air is pulled into your home. This measurement is called the air infiltration rate of a building. It is the only way to determine the air tightness of a home. In short, it reveals where you are leaking energy from your home.
How is a blower test performed?
A blower door test uses a specialized powerful fan, along with other equipment and softtware. The fan is mounted into the frame of an exterior door. All other windows and doors are sealed. Then the furnace is turned off.
As the fan pulls air out of the house, it lowers the air pressure inside. This is called negative pressure. As the higher outside air pressure flows in through all the unsealed cracks and openings. It is measured using a specialized digital infrared camera.
The goal of a blower door test is to determine how often inside air is replaced.
The air pressure flowing into the structure is measured in Air Changes Per Hour (ACH). This is the rate of air volume added or removed from a space (such as a house or a room), divided by the volume of the room. The rate is a measure of how many times in that specific space the air is replaced.
For all new construction under 2015 IECC, the measurement must be 3 or more ACH.
Who uses a blower door test?
Contractors, renovators, builders and homeowners do.
With the adoption of the 2015 IECC Residential Energy Codes, a blower door test is mandatory for many construction projects in Colorado. Recently, the Denver Metro Area adopted these new codes.
If you need to determine if your building or project is up to code, this test is required.
If you are a homeowner...
Homeowners may simply want to know if their home is sufficiently airtight. In that case, a blower door test along with infrared imaging may be recommended.
However, it is more typical for homeowners to do a complete home energy audit.
Are you replacing doors or fixing drafty windows? Are you doing a remodel? If you are a do-it-yourselfer, you may need to pass the test to obtain appropriate permits.
Colorado Residential Building Regulation R402.4.1.2
This regulation mandates a house be sealed tightly enough for energy purposes, but still be ventilated enough for occupant safety..
In Colorado, three air changes per hour must be tested and verified. Testing must 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).
Blower Door Testing is done by an independent third party
Where required by the code, testing shall be conducted by an approved third party. Green Home Consulting can perform these tests.
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.
Green Home Consulting holds all proper certifications and equipment to assist in this part of the construction process.