David Bolton The Keyed Removable Mullion on a Fire-Rated Pair: Why This One Component Shapes the Entire Opening Spec What This Article Covers This guide is written for commercial contractors, hardware specifiers, and facility managers who are configuring a fire-rated door pair and trying to understand how a keyed re... NFPA 80 exit devices fire-rated door pairs removable mullion windstorm compliance Sep 7, 2026
David Bolton Steel Flat Bar Astragals on Fire-Rated Door Pairs: Why the Meeting Stile Gap Gets Missed Until the Inspector Walks the Job The Problem That Shows Up at the Wrong Time The door pair is hung, the exit devices are set, the closer is adjusted, and the hardware contractor is ready to hand off the opening. Then the authority ha... NFPA 80 astragals commercial door hardware fire-rated door pairs seals and sweeps Jun 19, 2026
