ECN Forum Forums Code Related Discussion NEC & other Code issues mounting screws

ok ...where can i find the section that tells us that bugle head drywall screws are n/g for mounting metal j-boxes. i was knocked down for using drywall screws, not panhead screws. the inspector cited 110.3.

You won't find it.

110.3 can sometimes be a "catch-all" to knock a job down...while no specific Article is actually given by the AHJ

I am specifically citing 110.3(A)(1)

Where was your box mounted?

pancake boxes on the underside of a ceiling beam for paddle fans

If this is a pancake box for hanging the paddle fan he might be right. I seem to remember that the screws for mounting the paddle fan pancake box are special (sometimes). If your just using a standard pancake box to junction the wires, the only concern I'd have would be the fill in the box. And since he knows you are an inspector, he's probably being a little bit anal and telling you "Hey, those screws are for drywall"

When I install a box for a ceiling fan I use the screws that come with the box ONLY! The box is fan-rated, so the manufacturer should send screws capable of supporting the fan. I have used drywall screws to support boxes, but never a fan box. IMO, that's an accident waiting to happen, and it won't be very long.

Drywall screws are hardened,so have very little shear strength.How many times have you have then snap off when running them into old dry wood?

Uh ya, maybe use them for mounting a panel in between studs, use lag bolts for fan boxes.

Luke

I always get a kick out of the mounting screws supplied with "name brand" ceiling fans. Know which ones I mean?
An 8 pound fan with 5" long lag screws to hold it up to the ceiling. However the plastic ball that fits into the mounting bracket looks good enough for about 5 minutes or 5 miles, whichever comes first. And the bracket is real cheap potted metal.

For anything bearing weight, such as a pancake box for a fan - use 2"-3" pan heads. Drywall screws are great, IMHO, for mounting boxes for switches and outlets onto veritcal studs, but I wouldn't subject them to vibrations while bearing weight - if for no other reason, just the small size of the head looks bad from an engineering stand point.

It is kind of funny that most ceiling fans are actually held up by the two 8-32 screws going into the celing box, even though we take great measure to hold the box securely in place.

If the AHJ cited 110.0 (B), then he absolutely correct, IMO.

If the pancake box is ceiling fan rated, then screws for mounting the box came with the box. If you don't use them they you are violating the manufacturers specificiations.

This NEC rule applies to all UL listed electrical equipment.