Using tables from the National Fuel Gas Code or our Sizing & Application Guide, determine the diameter of venting required. The Sizing & Application Guide also offers tips on good design including multi-appliance system sizing and design. The System Design and Installation Guide is an additional resource.
• Used on a single-story building or on the top story of a multi-story building for Type BW gas vent
• The 26 gauge galvanized sheet metal extends down from the attic to the top of the ceiling plate
• Required by Los Angeles Code and UMC