Code Change Summary: A new code section provides requirements for relying on a ceiling fan canopy to provide additional box volume.

Quite often, a fan rated pancake box is used when roughing in the ceiling fan installation. Many of these boxes only have a total volume of 6 or 8 cubic inches. One single 14-3 (with ground) Nonmetallic sheathed cable will completely fill the 8 cubic inch fan box to its maximum allowable capacity. The same cable installed into a 6 cubic inch pancake box will over fill it and create a code violation (see 314.16).

The new code change is best understood when reading it along with the code language in 314.16, mainly subsection 314.16(A). The combination of both code sections allows the canopy of a ceiling fan to contribute to the total allowable box fill volume only if the canopy is marked with a cubic inch capacity in accordance with 314.16.

A few things to consider when applying the new code language:

• Most ceiling fan canopies are NOT marked with a cubic inch volume.
• If the fan canopy is NOT marked with a cubic inch volume, its volume CANNOT be considered to allow an overfilled pancake box to remain as is.
• If pre-wiring a home for ceiling fans that will NOT be installed before occupancy, the inspector will assume that the future fan canopy will NOT be marked with a cubic inch volume and will want the correct size box installed at rough.

Below is a preview of the NEC^®.  See the actual NEC^® text at NFPA.ORG for the complete code section. Once there, click on the “free access” tab and select the applicable year of NFPA 70 (National Electrical code).