Wood and glass between electrical box and sconce

A customer (an architect) in Philadephia, PA has designed a bathroom with a mirror over the vanity, backed by 1/4" luan plywood. In the middle of the mirror he has called for sconces to be mounted; screwed into “mud rings” (which only extend to the face of the drywall) on metal electrical boxes.

My question is, since there will be a space between the mud ring and the light fixture (the thickness of the luan and the mirror), does this present a fire hazard and therefore a code issue, though neither the luan nor the mirror will come within a 1/2" of the mud ring?

If this is an issue, is the only way to resolve it by getting extension mud rings that extend to meet the light fixture directly?

Philadelphia, PA

The part going through the plywood is the problem. When going through combustible material the box/extension has to be flush or protrude.

**312.3 Position in Wall.
**In walls of concrete, tile, or other
noncombustible material, cabinets shall be installed so that
the front edge of the cabinet is not set back of the finished
surface more than 6 mm (1⁄4 in.). In walls constructed of
wood or other combustible material, cabinets shall be flush
with the finished surface or project therefrom.

I agree 100% with Greg, tell them to go get a Arlington Extention Ring and they will be fine. This will allow for the gap and allow it to meet code.


These puppies SAVED my butt on a recent finish out.

The builder changed from 1/2 Sheet Rock to 5/8 Sheet Rock…BUT then decided at the last minute ( well after I left the rough in ) to put up 5/8" wood paneleing ( Wainscoting…not sure how to spell that…sorry) so I came back and WHAMO…screwed…these little bad boys saved the DAY !

THANKS to the GUYS who can actually SPELL…I edited it since I can’t and did not take the time to try…lol- Thanks Guys


lol…Thanks…I try NOT to strain my brain when typing on the boards…lol