How Duct Sealing Works

By November 17, 2018April 19th, 2019Uncategorized

Want to geek out more on how this happens? Read on. For example:  When a 2.5 ton HVAC system is working properly the return is sucking in 1000 CFM.  When there are no leaks in the ducts the supply ducts supply the home with that same 1000 CFM.  It is a closed system that keeps the pressure in the house fairly neutral.  When there are leaks in the supply ducts; say about 18% which might be about average for the supply side, not all 1000 CFM is making it back to the return.  Only 820 CFM is making it back to the return side of the system.  It is a machine, and it doesn’t know that it’s only getting 820CFM.  It is going to pull the remaining 135 CFM from wherever it can.  Air flows through the path of least resistance.  So if you have a pier and beam home the unwanted air may be coming through the floors, if you’ve got leaky windows it may be through the window cracks. This means that all that heat, humidity and poor quality air is now coming into your home causing your AC to work harder and you to be less comfortable.

Aeroseal was featured on Season 12 of “Ask This Old House”. Richard Tretheway wraps up the episode with the comment “I’ve never seen a better solution for fixing air-conditioning ductwork.” We agree! Jump to scene 4 once the video starts to see Aeroseal in action.