Ducts should be air-sealed with metal tape and/or duct sealants such as Mastic. Alternatively, there is a new approach available to the homeowner that involves spraying an aerosol sealant inside the ducts. This has shown to be quite effective and must be conducted by a professional with the proper equipment. Lastly, believe it or not, duct tape is not effective or recommended for sealing ducts — so do not use it.
Tim Gould is the director of Informed Energy Solutions, Inc., located in Amesbury. Contact him at 978-388-6349. On the web at www.InformedNRG.com.