Duct Blaster Testing
Duct Testing for New Construction
If a new home has duct work through unconditioned space, such as an attic, uninsulated basement or crawlspace, the duct work must be tested for air tightness. This duct test is required to meet PA residential building code. This test is done with a duct blaster. A small heavy-duty fan is put on the air handler or a central return grill. The fan pressurizes the duct work and measures air leakage with pressure gauges.
The building code requires duct work that is tested to be airtight, 4FCM per 100 square feet of conditioned area with the fan running at standard pressure. This is a high standard that can only be achieved with an airtight air handler and well-sealed duct work.
Pennsylvania is under the 2015 International Energy Conservation Code (IECC), part of the 2015 International Residential Code.