The Ceiling Became a Plenum After I Piped It What one master plumber learned the hard way about plastic pipe in return-air plenums — and why the answer isn’t always to tear it out. Enrique Leal October 5, 2026 The code does not say the pipe has to come out. It says the material exposed in the plenum has to comply. There is more than one way to get there, and only one of them involves a demo crew.Read More
