Air sealing is an essential part of any duct system, as it helps guarantee that air conditioning reaches its destination at the desired temperature and without absorbing any contaminants. To ensure proper sealing around diffusers in a duct system, there are a few steps to follow. To begin with, it is recommended to consult the standard work specifications from the Department of Energy for additional guidance on how to place and seal duct covers. Air sealing should be done with putty, foam, or any other equivalent material.
For extra protection against air leaks, a Roflex joint can be used, which allows for the pipe to be moved in and out even after sealing it with air. Additionally, fan door tests can help indicate whether the openings in the ducts that lead to an unconditioned space have been properly sealed. When sealing the inner part of the duct system, HF sealant should be used between the elements of the vertical frame. This will provide redundancy in air sealing and help protect the house from air leaks. If sealing from the attic or mezzanine side, insulation should be removed as needed to access the areas to be sealed.
Additionally, Roxul Comfortboard 80 can be added to the pipe to try to add an R value to the inside of the PVC pipe. When air sealing around diffusers in a duct system, it is important to remember that tubes are easy to manipulate and move around pipes, electrical appliances, or any other structural component that cannot be easily relocated. By following these steps and consulting standard work specifications from the Department of Energy, you can ensure that your duct system is properly sealed and will provide long-term protection against air leaks.
