Blower Door Tests
Technology
Snapshot & Benefits:
Blower doors are a testing method used by professional energy auditors
and raters to help determine a home's air tightness. There are numerous benefits
to making sure your home is properly air tight. Having an air tight home reduces
energy consumption due to air leakage, helps to avoid moisture and condensation
problems, helps to avoid uncomfortable drafts caused by cold air leaking in from
the outdoors, and to make sure that the home's air quality is not too
contaminated by indoor air pollution.
A blower door is a
powerful fan that mounts directly into the frame of an exterior door. The fan
pulls air out of the house, lowering the interior air pressure. As a result the
higher outside air pressure then flows in through all unsealed cracks and
openings. The auditors may use a thermal imaging camera and a smoke pencil to
help them detect air leaks.
It is important
that the auditor use a calibrated blower door rather than one that is
uncalibrated. By using a calibrated blower door the auditor can do more than
just find leaks. They can use the information to quantify the amount of air
leakage and the effectiveness of any air-sealing job.
Estimated
Cost Savings:
A typical cost of a blower door test ranges from $200 on up depending on
the size and complexity of the structure. Once air leaks are discovered in a
home, depending on their location and size, they can often be fixed on your own
or at an inexpensive price point. The identification of sources of energy loss
in a home can result in significant savings through improved energy efficiency.
Issues:
Be aware to as whether or not your energy auditor is using a calibrated blower
door, which is proven to be more effective than one that is uncalibrated. Be
aware that some contactors who market themselves as being able to perform blower
door tests may not have the appropriate education or certification to accurately
perform and analyze the results. To avoid this, testing should be performed by
certified contractors, such as Home Energy Rating Systems raters, Building
Performance Institute analysts, or Home Performance with ENERGY STAR
contractors.
Regional
Issues:
The only regional issues that exist with blower door tests is based on the
interpretation of the data. The blower door test can be completed in nearly any
climate, but it is important to understand the results in the context of that
region.
Installation
(Getting It Done):
Check out our
energy ratings and audits page on our website at
http://ecobroker.com/misc/greenresource.aspx?id=6 for links to professionals
in the field. Some other places where you could find professionals are through
your state or local government or through your local utility company. Some
governments and utilities may even help to subsidize the costs of the blower
door test.
More
Information On This Topic:
U.S. Department of
Energy -
Blower Door Tests
Green Building
Advisor -
Blower Door Basics
eXtension -
Blower Door & Infrared Home Energy Assessments