These pictures were taken inside of duct work that measured about 10’0” high x 40’0” wide. Steel support bracing like this is very typical in large duct work, although supports can be on the outside of the duct work.
Note that the expansion joint between the support columns is about 2’6” wide and runs completely around the inside perimeter of the duct work. A duct balloon that measures 40’ wide x 10’ high x 3’ deep can be installed in this area and become secured by the duct work supports to prevent any movement.
Copyright 2010 by G.R. Werth & Associates, Inc. - All rights reserved
Duct Balloon
Inflatable Isolation Barriers
