Code Q&A

Dec. 13, 2007

Is it permissible to run heating/air-conditioning duct 4 feet above a panelboard if the ductwork services the room where the panelboard is located?

Mike Holt

Q. Is it permissible to run heating/air-conditioning duct 4 feet above a panelboard if the ductwork services the room where the panelboard is located?

A. No. The footprint space (width and depth of the equipment) extending from the floor to a height of 6 feet above the equipment or to the structural ceiling (whichever is lower) must be dedicated for the electrical installation. No piping, duct, or other equipment foreign to the electrical installation can be installed in this dedicated footprint space [110.26(F)].

About the Author

Mike Holt

Mike Holt is the owner of Mike Holt Enterprises (www.MikeHolt.com), one of the largest electrical publishers in the United States. He earned a master's degree in the Business Administration Program (MBA) from the University of Miami. He earned his reputation as a National Electrical Code (NEC) expert by working his way up through the electrical trade. Formally a construction editor for two different trade publications, Mike started his career as an apprentice electrician and eventually became a master electrician, an electrical inspector, a contractor, and an educator. Mike has taught more than 1,000 classes on 30 different electrical-related subjects — ranging from alarm installations to exam preparation and voltage drop calculations. He continues to produce seminars, videos, books, and online training for the trade as well as contribute monthly Code content to EC&M magazine.