Florida’s Blower Door Testing FAQ

Since July 1st, 2017, without exception, new non-commercial houses built in Florida have been mandated to fulfill the Blower Door or “House Infiltration” requirement that was recently added to the 2014 Florida Building Code. This requirement does not apply to new homes that were permitted for construction before July 1st of 2017. The FAQs listed below are intended to clarify for builders and homeowners the specific requirements outlined in this new addition to the Florida Building Code:

Where can I find the Florida Blower Door testing requirements?

The requirements are listed in Section R402.4.1.2, a revisional code added to the 5th edition of the 2014 FBCEC (Florida Building Code, Energy Conservation). You can access this supplemental code here.

What exactly does the Blower Door add-on require?

It stipulates that each house can have no more than seven air changes per hour when certain air pressure is simulated.

The test uses a blower door fan to simulate this pressure, which is 50 pascals (or 20 miles per hour.) The air volume inside a home that is subjected to this wind pressure should not swap out with air outside the home any more than seven times. Testing a house of any size or layout at 50 pascals of wind pressure allows one to reasonably compare air volumes in specific areas throughout the home.

Do multifamily residential homes have to adhere to the Blower Door screening requirement?

Yes, all residential structures with three or fewer floors must adhere to the Blower Door requirement.

How difficult is it to pass the Blower Door evaluation?

Any home that satisfies the air sealing standards outlined in chart R402.4.1.1 of the Florida Building Code should pass the test with no difficulty.

What is the price of Blower Door testing?

The average cost of a single Blower Door test is $150.

How long will it take to carry out the test?

After all equipment is set up, the test will take roughly half an hour to complete.

When is the best time to perform the test?

Only after the home is entirely constructed, with all weather-stripping applied, all utilities like electricity and water turned on, and all walls visually inspected and free of holes.

How will I obtain the results?

Most testing companies leave a written copy of the results on the premises for the building contractor, but a few may electronically deliver them.

What is the purpose of Blower Door testing?

The test intends to determine whether a home is properly insulated and protected against air leaks, which allow warm and/or filtered air inside the home to escape and cold or contaminated air from outside to breeze in.

Does the home have to be mechanically ventilated?

Homes that are determined through Blower Door testing to have fewer than three hourly air changes must be mechanically ventilated.

Why do homes with three or fewer air changes per hour need mechanical venting?

Air does not circulate as it should in houses with less than three hourly air exchanges. Tests have shown that the air in these homes holds excessive moisture and stagnates easily. Therefore three hourly air changes are required to keep the air clean and safe to breathe.