Aeroseal is a product that seals small leaks in the ductwork. No attic work is required by the crew to work the equipment. It is monitored by a computer program that tells when the pressure of the ductwork is low enough that most of the leakage has been sealed.
The plus side to Aeroseal is that:
1. It is able to reach inaccessible parts if the attic such as flat roofs.
2. No attic work has to be done.
3. Unlike radiant barrier, it reliably works regardless of how it was installed.
The down sides to Aeroseal are:
1. It does not seal larger leaks, which are the most important leaks you have. Since crews assume all the duct leakage was found and sealed, if they go into the attic, they will not look for large leaks in the ductwork.
2. Aeroseal is not cost effective. It is expensive, usually 3-4 times more expensive than sealing the ductwork by hand. Aeroseal costs starts from $2000 for each air conditioning unit. With the extra money saved by using hand duct sealing, you could have a super insulated attic, a variable speed pool pump or any other energy saving upgrades done. Hand sealing is not as glamorous as the Aeroseal technology but who cares if you are saving thousands of dollars on something that costs the same and no one will ever see?
3. It is easily misunderstandable. If you are not working with Aeroseal everyday, chances are the printout you receive from Aeroseal showing your leakage reduction will look great. But you need an experienced energy auditor to be able to tell you in the first place if you need it or not. Then if you have leaks which are larger than 5/8" which Aeroseal will not be able to close up. Chances are likely that if a company does Aeroseal, they will not train their sales staff and auditors to sell hand duct sealing and will not look for larger gaps in the ductwork.
4. Aeroseal only lasts 10 years according to the Aeroseal website, hand sealing with mastic has a life of 30 years.
In our opinion Aeroseal works effectively for smaller holes and is ideal for flat roof homes. On older homes, Aeroseal just doesn't come close to the effectiveness of hand sealing the ducts because a crew hand sealing will be able to secure the ductwork with metal screws, check the connections and spend a lot more time in your attic, which increases the chances for finding and fixing problems that the auditor did not find during his initial inspection. Aeroseal requires no time in the attic.
Ductwork leakage is caused by one or several of the following reasons: inferior workmanship, torn and missing external duct wrap, improperly installed duct sealants. By properly sealing your ductwork, you are avoiding lost of lost air and money thrown into your attic.