Great post Alison! Even though we like sheet steel, specifically for trunk lines, big duct techniques could be exorbitantly expensive if finished in all metallic. There are times wherever flex duct (or sections of it) can assist to reduce prices. Within our retrofit work, we’d instead see a buyer by https://worldlistpro.com/story19990585/getting-my-fire-resistant-ductwork-installers-to-work