Code Q&A: NEC Requirements for Expansion Fittings on PVC Raceways

Dec. 28, 2023

Test your knowledge of the NEC.

Q. What is the NEC requirement for expansion fittings on PVC raceways?

See answer below.

A. As stated in Sec. 352.44, if PVC conduit is installed in a straight run between securely mounted items such as boxes, cabinets, elbows, or other conduit terminations, expansion fittings must be provided if the expansion or contraction length change (in accordance with Table 352.44) is expected to be ¼ in. or greater.

Author's comment: When determining the number and setting of expansion fittings, you must read the manufacturer’s documentation. For example, instructions for Carlon expansion fittings for PVC conduit say that when it has sunlight exposure, 30ºF must be added to the high ambient temperature.

These materials are provided to us by Mike Holt Enterprises in Leesburg, Fla. To view Code training materials offered by this company, visit www.mikeholt.com/code.

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.