Blower Door Testing for Code Compliance in Maryland

Blower door testing is a crucial step in ensuring that buildings in Maryland meet state energy codes and building standards. This test measures the airtightness of a structure by using a calibrated fan to depressurize the home, identifying air leaks and areas where energy loss occurs.

Why Blower Door Testing Is Required in Maryland

Maryland's building codes, particularly the Maryland Energy Conservation Code, require blower door testing for many new construction projects and significant renovations. The purpose is to improve energy efficiency, reduce utility costs, and enhance indoor comfort by minimizing uncontrolled air infiltration.

What the Test Involves

A professional technician installs a blower door—a powerful, calibrated fan fitted into an exterior door frame. The fan pulls air out of the building, lowering the indoor air pressure. This pressure differential causes outside air to enter through leaks, which can then be detected using smoke pencils, infrared cameras, or simply by hand-feeling.

Benefits of Blower Door Testing

• Code Compliance: Passing blower door testing ensures the building complies with Maryland’s energy code requirements.

• Energy Savings: Identifies leaks that contribute to heat loss or gain, allowing for targeted air sealing.

• Improved Comfort: Reduces drafts, leading to more consistent indoor temperatures.

• Indoor Air Quality: Properly controlled ventilation improves overall air quality.

• Resale Value: Meeting code and demonstrating energy efficiency can increase property value.

When to Schedule Blower Door Testing

The best time to schedule blower door testing is after rough construction and air sealing are complete but before drywall installation. This timing allows contractors to identify and address leaks while access is still possible.

Finding a Qualified Tester in Maryland

Blower door testing must be performed by qualified and certified professionals, often trained through RESNET or similar organizations. Maryland builders and homeowners should ensure their testing provider meets these qualifications for accurate results and code compliance.

Blower door testing is a mandatory and effective method to meet Maryland’s energy code standards, ensuring buildings are safer, more efficient, and more comfortable for occupants.