$300 – Duct leakage testing. With the adoption of the 2018 IRC, ALL ducts in new construction in the Denver Metro area will be required to be tested for air leakage*

2019 Denver Building And Fire Code — Duct Testing Amendments:

R403.3.3 Duct testing (Mandatory). The duct work in a building or dwelling unit shall be pressure tested in accordance with ANSI/RESNET/ICC 380 or ASTM E1554 for air leakage. The maximum total leakage rate for duct in any building or dwelling unit under any compliance path shall not exceed 6.0 cubic feet per minute per 100 square feet of conditioned floor area served, (6cfm/100sqft), when the air handler is installed at the time of the test. When the air handler is not installed at the time of the test, the total leakage shall be less than or equal to 3.0 cubic feet per minute per 100 square feet of conditioned floor area; (3 cfm/100 sq ft). Registers shall be taped or otherwise sealed during the test. Testing shall be conducted at the rough‐in stage or post‐construction by one of the following methods:

1. Rough‐in test: Total leakage shall be measured with a pressure differential of 0.1 inch w.g. (25 Pa) across the system, including the manufacturer’s air handler enclosure if installed at the time of the test. Registers shall be taped or otherwise sealed during the test.
2. Post Construction test: Total leakage shall be measured with a pressure differential of 0.1 inch w.g. (25 Pa) across the entire system, including the manufacturer’s air handler enclosure. Alternatively, a duct leakage test to outside conditioned space with a pressure differential of 0.1 inch w.g. (25 Pa) with reference to the outside across the entire system including the manufacturers’ air handler may be performed. Registers shall be taped or otherwise sealed during the test.Exceptions:
   1. A duct air‐leakage test shall not be required for ducts serving ventilation systems that are not integrated with ducts serving heating or cooling systems.
   2. If the HVAC duct system is serving less than or equal to 1,200 square feet of conditioned floor area, the allowable duct leakage shall be 72 cubic feet per minute or less. A written report of the results of the test shall be signed by the party conducting the test and provided to the code official.
   
   Exception: If the HVAC duct system is serving less than or equal to 1,200 square feet of conditioned floor area, the allowable duct leakage shall be 72 cubic feet per minute or less

In order to pass the test, it is important to apply rigorous air sealing measures using duct mastic and aluminum foil tapes on all joints, branches, elbows etc. During the test, a blower fan will pressurize the duct system and a total air leakage number will be displayed. A duct leakage test can be performed at rough-in before drywall is hung, or at post-construction. Performing the test during rough-in is highly recommended so any problem areas can be addressed.

A certificate will be issued upon completion to present to the city inspector.

Other Counties & 2015 IRC Code Requirements:

For 2015 IRC code requirements and other counties outside of Denver, testing ducts is a requirement only for ducts that have runs through unconditioned spaces such as attics and crawlspaces.  In order to pass the test, ducts can not have more then 4% leakage of total sq footage. For example, a 2000 sq foot home is allowed 80 CFM (cubic feet per minute) of air leakage per the 2015 IRC Energy Code.

Passing The Test

If you are not passing your duct leakage test, we will blow theatrical smoke in your ducts and search for leaks. The blower fan pushes the smoke through the ducts so we can see where any leaks are located. We will work with your HVAC contractor to isolate leaks while the fan is running. The test fee includes 1.5 hours of diagnostics and trouble shooting; additional trouble shooting is charged at $50 per hour.

* $300 for first system. $250 each additional system.