When should Aerosealing be used and when is manual ductwork sealing recommended?

Manual ductwork should be used:
Aeroseal the ductwork should be used:
- Within the first 3 feet of the air handler, furnace or package unit
- Gaps larger than 5/8". An energy auditor will be able to identify larger holes with a blower door test. It is typically not a good idea to rely on the Aeroseal technicians to find the larger holes since they typically just "blow and go."
- When the ductwork is 100% accessible.
- Manual ductwork sealing can be applied thicker, which is better than the thin coat of glue Aeroseal leaves.
Aeroseal the ductwork should be used:
- When the ductwork is not accessible for rectangular sheet metal ductwork in attics, walls and crawlspaces.
- The the ductwork travels between floor cavities and is inaccessible.
- The ductwork travels to an inaccessible part of the house (just because a large or inexperienced technician can't reach an area in the attic, does not mean it is inaccessible).
- The ductwork is extensively wrapped in metal wires and insulation.