Aerosol: A Breakthrough Sealing Technology for Air Ducts

Leaky ducts are one of the major causes of air leakage from the HVAC units. A variety of duct sealants are available in the market to seal duct such as mastic, foil tapes, and such others. Duct tapes are not recommended for sealing leaks as they cannot withstand extreme temperatures. Recently another breakthrough technology has come in the arena of duct sealing in form of Aerosol duct sealing. This seals leaks from inside out. The technician uses Aerosol software to correctly measure the size of leaks in the duct in residences or commercial spaces. The sealant is applied from inside the duct by pumping aerosol into it. These polymer particles stick first to the edges of a leak and then to each other until the leak is plugged. This technology was born at Lawrence Berkeley National Laboratory, whose IAQ scientists tested it. The useful research was sponsored by US Environmental protection agency, US dept. of Energy, Electric Power Research Institute, and California Institute of Energy and Environment.Besides sealing leaks, Aerosol also plays an important role in controlling temperatures in all rooms, enhancing indoor air quality, and reducing odors and fumes. It also ensures a good airflow and proper ventilation.

 How aerosol is applied?

• The duct sealing device attached to a single point in the duct.

• The leakages in the duct system are detected and measured with software.

• Thereafter, the well registers ae covered to allow trickling of air only through the leaks.

• Aerosol Sealant is pumped into the ducts for approximately 1 hour.

• Small aerosol particles remain suspended in the air due to continuous air movement. When the air torrent takes sharp turns to make their way out through the leaks, the particles start adhering themselves to the edges of the leaks. Thereafter they stick to each other to close the gap. 

• Once the job gets done, you are provided with a documentation that the procedure has worked. This is done after monitoring the leakage levels with the software. The entire procedure would take 4 to 8 hours.

What are the advantages of aerosol?

• As the substance is pumped through the ducts it can reach at remote corners which are otherwise inaccessible.

• The process requires less time and effort.

 What are the downsides of using Aerosol?

• Aerosol is not meant for sealing large leakages. Aerosol sealing is not recommended for gaps larger than 1/4-inch.

• It is quite an expensive sealant. Its cost is usually 3-4 times higher than sealing the duct work with mastic at home. Aerosol costs starts from $2000 for each air conditioning unit. Moreover, you will have to pay the service charges to the professionals who come and apply it on your ducts. It cannot be done by an amateur. It has been found that the money you can save by using mastic or foil tape can be used to insulate the attic, buy a variable speed pool pump, or get other energy saving upgrades done.

 • Aerosol only lasts 10 years, whereas hand sealing with mastic can last up to 30 years.

Hand sealing has many advantages over aerosol.Aerosol is only meant for smaller holes. It will not be very effective for older homes. If you get a professional team for sealing your ducts with hand sealants then they will apply multiple ways to seal your ducts. They will use metal screws to secure ducts besides applying mastic and foil tapes in places. They will inspect the connections closely spending lot more time in the attic. Aerosol needs no time in attic which is both its advantages well as disadvantage. By properly sealing your duct work, you are avoiding loss of air and money thrown into your attic.