Sinking Feeling

What’s Wrong Here? Hint: This Gives Me a Sinking Feeling

March 14, 2024
Think you know how this installation violates the NEC?

Hint: This gives me a sinking feeling

I’m not sure what happened with the position of the box installed for this fire alarm speaker/strobe. Was another layer of sheetrock added to the wall? Was the box originally set back too deep? Or was it something else? Whatever the reason might be, the end result is a violation of Sec. 314.20.

Installations in noncombustible walls are permitted to have the box set back no more than ¼ in. from the finished surface. This box is set back about an inch. That is too much. An extension ring, plaster ring or some other listed box extender could be installed to solve the problem here. Another more invasive option would be to rip the wall open and reposition the original box, so it complies with the ¼ in. set back. I think installing an extension ring may be the easiest solution here. FYI- Installations in combustible surfaces are not permitted to be set back at all from the finished surface.

About the Author

Russ LeBlanc | Owner

Russ started in the electrical trade as an apprentice in 1985. He worked his way up to become a Journeyman Electrician and then eventually became a Master Electrician and Licensed Construction Supervisor. In 1999 Russ become an Electrical Instructor for The Peterson School of Engineering in Massachusetts where he developed his passion for teaching, and quickly became Department Head of Electrical Instruction. Russ has taught thousands of apprentices, electricians, engineers, inspectors, and other electrical professionals during his career as an instructor. He continues to provide electrical professionals with Electrical Code seminars, Arc-Flash Awareness training seminars and educational material through his LeBlanc Consulting Services in North Reading, MA whose specialty is educating electricians. He has been an active member of the NFPA Electrical Section and has authored hundreds of National Electrical Code proposals and comments which have become Code rules to improve the safety for the electrical industry. Russ is also an IAEI certified Electrical Inspector.

Please visit for more information.

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