Florida Blower Door Testing: What Builders and Multifamily Teams Need to Know

Originally published in 2017. Updated June 2026 to reflect current Florida Building Code considerations, testing practices, and RunBrook services.

Blower door testing is required under the applicable Florida Building Code for new residential homes and certain low-rise multifamily buildings.

For production home builders, multifamily developers, contractors, and project teams, the test is more than a final compliance step. Proper planning, building preparation, testing, and documentation can help identify air-leakage issues, reduce failed tests and repeat visits, and keep inspections and project closeout moving.

What Is a Blower Door Test?

A blower door test measures the overall airtightness of a home or residential unit. It determines how much air passes through gaps and openings in the building envelope under controlled pressure.

Testing can also help identify where air leakage may be occurring, including around:

  • Windows and exterior doors

  • Plumbing and electrical penetrations

  • Attic access points

  • Recessed fixtures

  • Wall and ceiling transitions

  • Other gaps in the building envelope

Airtightness is important because uncontrolled air leakage can affect energy use, comfort, moisture management, indoor air quality, and HVAC performance.

How Does a Blower Door Test Work?

Blower door testing equipment includes a temporary frame and flexible panel installed in an exterior doorway, a calibrated variable-speed fan, and instruments that measure airflow and pressure.

During the test, the fan lowers the air pressure inside the home. The pressure difference causes outside air to enter through gaps and openings in the building envelope. The technician uses the resulting measurements to calculate the home’s air-leakage rate and determine whether it meets the applicable requirements.

The results may also help the project team identify air-sealing vulnerabilities that should be corrected before final inspection or occupancy.

Below are four important things to know about blower door testing in Florida.

4 Things to Know About Florida Blower Door Testing

1. Confirm the Applicable Code Requirements

Blower door testing is required for new residential homes and applicable low-rise multifamily buildings under the Florida Building Code.

However, the specific requirements for a project may depend on factors such as:

  • The applicable code edition

  • Permit and construction dates

  • Building type and configuration

  • The selected energy-compliance path

  • Project-specific certification or rating requirements

  • Requirements established by the authority having jurisdiction

Builders and project teams should confirm these requirements early rather than waiting until the home or building is ready for final inspection.

Testing is generally performed when the building envelope is substantially complete and the home or unit is near occupancy. Windows and exterior doors should be installed and properly sealed, utilities should be available, and the systems and finishes that affect the test should be in place.

Confirming the required testing conditions, procedures, and documentation in advance can help avoid scheduling problems and unnecessary repeat visits.

2. Build Tight and Ventilate Right

Blower door testing helps verify whether the building envelope has been sealed as intended.

The results can reveal installation or construction issues such as:

  • Poorly sealed windows or doors

  • Missing or incomplete weather stripping

  • Gaps around utility penetrations

  • Leakage at attic access points

  • Incomplete air-barrier transitions

  • Recurring air-sealing issues across repeated plans or units

Identifying these problems is especially important for production housing and multifamily construction. A recurring detail or installation issue can affect multiple homes, units, or buildings if it is not identified early.

A tighter building envelope can reduce uncontrolled air leakage, but airtightness must be coordinated with the project’s ventilation strategy. Blower door testing should not be treated as an isolated closeout task. Airtightness targets can affect energy modeling, ventilation, HVAC performance, moisture management, and certification requirements.

For larger projects or repeated home plans, pre-test reviews and quality-assurance checks can help identify common leakage points before they affect multiple residences.

3. Coordinate Testing Before Project Closeout

Successful blower door testing begins before the technician arrives on site.

The project team should confirm that the building is ready, the appropriate systems and utilities are available, access has been coordinated, and the relevant documentation is understood.

On production housing and multifamily projects, testing may need to be coordinated across:

  • Multiple homes or units

  • Separate buildings and construction phases

  • Different site supervisors and trade partners

  • Repeated plans or unit types

  • Inspection and turnover schedules

  • Rating, certification, or sampling requirements

Late or poorly coordinated testing can lead to failed tests, return visits, rework, incomplete documentation, and delays during final inspection or closeout.

Early coordination also allows the team to clarify responsibilities. For example, the builder, insulation contractor, HVAC contractor, window installer, and other trades may each affect the building envelope and the final test result.

RunBrook works with construction teams to schedule testing at the appropriate stage, communicate results clearly, and help identify issues that could interfere with inspections or project completion.

4. Understand How Testing Relates to HERS and Certification

Blower door testing may also be required as part of a HERS Rating or an energy-efficiency or green-building certification program.

A HERS Rating combines energy modeling with required field inspections and performance testing to evaluate a home’s overall energy performance. Depending on the home and the applicable standards, the rating process may include:

  • Blower door testing

  • Duct leakage testing

  • Energy modeling

  • Insulation and air-sealing inspections

  • Verification of energy-related equipment and building features

The lower the HERS Index score, the more energy efficient the home is relative to the applicable reference home.

Blower door testing may also support requirements associated with programs such as:

  • ENERGY STAR

  • National Green Building Standard

  • LEED

  • Florida Green Building Coalition

  • DOE Efficient New Homes

Each program has its own inspection, testing, documentation, and verification requirements. These requirements should be identified before construction begins so that required inspections are not missed and testing can be coordinated efficiently.

It is also important to distinguish blower door testing from duct leakage testing. A blower door test measures leakage through the building envelope, while a duct leakage test measures leakage from the HVAC duct system. Depending on the project, both may be required.

The Right Testing Partner Can Simplify the Process

The physical blower door test can often be completed efficiently, but a successful testing program requires more than placing equipment in a doorway.

The testing professional must understand the applicable procedures, confirm that the building is ready, coordinate with the project schedule, report the results accurately, and communicate any failures or recurring issues clearly.

This becomes particularly important on multifamily and production housing projects involving hundreds of homes or units. Consistent scheduling, field procedures, reporting, and communication can help teams avoid confusion and maintain progress across the project.

RunBrook has performed thousands of building-performance tests and supports production housing, multifamily developments, custom homes, and other residential projects throughout Florida and beyond.

Our services include:

By connecting design and analysis with field testing and documentation, RunBrook helps project teams identify issues earlier, reduce compliance risk, and move efficiently from planning through final verification.

Plan Blower Door Testing Before the Final Inspection

Blower door testing should not be treated as a last-minute item.

Confirming the applicable requirements, preparing the building properly, coordinating trades, and scheduling testing at the appropriate stage can help reduce failures, rework, and closeout delays.

For production housing and multifamily projects, establishing a consistent testing and reporting process is especially important. The right approach can help the project team maintain quality across repeated plans, buildings, and phases while keeping inspections and turnover on schedule.

Planning blower door testing for a homebuilding or multifamily project? Contact RunBrook to discuss testing, documentation, HERS, and project coordination requirements.

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