Understanding Blower Door Tests: A Key to Energy Savings and Home Comfort

Blower door tests are essential for assessing a home’s energy efficiency by pinpointing air leaks. These tests, performed by energy professionals, reveal the airtightness of your home, helping you understand where energy is wasted and where improvements can increase comfort and reduce costs.

What is a Blower Door Test?

A blower door test involves mounting a powerful fan in an exterior doorway, calibrated to pull air out of the house and lower indoor air pressure. This pressure difference forces outside air to enter through any cracks, gaps, or unsealed areas, making leaks visible. Professionals may also use infrared cameras or smoke pencils to locate leaks precisely. This process provides a clear picture of your home’s air infiltration rate, helping identify areas where air escapes or enters unexpectedly.

Why is a Blower Door Test Important?

Knowing your home’s airtightness has several advantages:

1. Energy Savings: Reducing air leakage cuts down on heating and cooling expenses, saving energy.
2. Improved Comfort: Sealing leaks prevents drafts, making your living space more comfortable.
3. Moisture Control: Proper sealing prevents condensation issues that can lead to mold.
4. Cleaner Air: Controlled airflow helps keep outdoor contaminants, pests, and odors from infiltrating your home.

How Blower Door Tests Work

A blower door consists of a frame, flexible panel, variable-speed fan, and digital pressure gauge, often connected to a manometer that measures airflow. Professionals may use calibrated blower doors, which provide precise measurements of air leakage both before and after air-sealing, ensuring accurate diagnostics. Non-calibrated doors, on the other hand, locate leaks but can’t quantify airtightness.

Preparing for a Blower Door Test

To prepare:

• Be ready for a walk-through with your auditor and point out drafty areas.
• Clear access to all parts of the home, including closets, attics, and crawl spaces.
• Make sure wood fires are extinguished and ashes removed.
• Expect your auditor to secure windows and doors, close fireplace dampers, and control any appliances with atmospheric venting.

By understanding and preparing for a blower door test, you’ll help ensure an effective audit that maximizes energy efficiency and comfort in your home.