Duct Leakage Testing for New Construction in Massachusetts 2026
Duct leakage testing is required for all new construction with forced air HVAC systems in Massachusetts Stretch Code municipalities. HERS Rating Company performs duct leakage testing across all 351 MA cities.
Massachusetts Duct Leakage Standard
The MA Stretch Code 2021 requires total duct leakage of less than 4% of design airflow (at 25 Pascals). Ducts must be carefully sealed at all connections, boots, and air handler cabinets.
What Happens During a Duct Leakage Test?
All supply and return registers are sealed. A calibrated fan pressurizes the duct system to 25 Pascals. Airflow required to maintain pressure is measured and compared to total design airflow. If ducts fail, corrections are made and HERS Rating Company retests.
Duct Testing Locations
Boston | Worcester | Cambridge | All 351 MA Cities →. Call 617-584-1809.