Latest Discussions : Electrical & Lighting


02:12PM | 01/23/10
Member Since: 12/01/09
8 lifetime posts
The background: I am remodeling my kitchen. I replaced the light over the sink with twin pendant lights. To mount them I went into the attic, cut holes in the ceiling plasterboard, installed plastic ceiling boxes, and ran NM cable to the boxes. Then I mounted the base plate of the lights on the boxes, and the lamps hang down about 20 inches.

In the attic, under the floorboards, is loose pink fiberglass insulation, apparently just poured in. To get to the where I needed to mount the boxes, I gathered up the insulation between the joists and stored it in plastic garbage bags. Of course, I used goggles, gloves, and a mask while working with the fiberglass.

Here is my question: I have heard that if you have recessed lighting installed in a ceiling, you need to keep insulation a certain distance away from the box. Does the same apply to my ceiling boxes? They do not have any lights in them, just the wires that connect to the pendant lights.


Tom O

05:12AM | 01/24/10
Member Since: 09/17/02
476 lifetime posts
There is no restriction that I'm aware of about covering a junction box with insulation.

However, your post mentions floorboards in the attic and I'm not sure if you installed the junction box under them. A junction box would not be allowed under the floorboards.


06:57AM | 01/24/10
Member Since: 12/01/09
8 lifetime posts
Thanks for the quick reply.

As it turns out, this is a partially-finished attic which is built like this: The plasterboard which forms the ceiling of the first floor is attached to furring strips which run perpendicular to the joists. That plasterboard has some sort of silvery coating on the back (up) side. Then the joists are covered on top with tongue-and-groove planks up to about two feet from the eaves. The insulation fills the space between the joists under the floorboards, and also the space between the joists that is not covered. As it turned out, the lights are close enough to the outside wall that the ceiling boxes are in the area with no floorboards.

I did attach some wood strapping across the joists and stapled the cables to it for support.

Now for my new question: Why do you say that a junction box would not be permitted under the floorboards? How is this different from the box for a ceiling fixture on the first floor of a two-story house? Maybe it was not clear from my description that the inside of the box is still accessible from below, by removing the pendant lamp. Is that what you were concerned about?

Thanks again.


12:45AM | 01/26/10
Member Since: 01/09/07
199 lifetime posts
"Is that what you were concerned about?"

Yes, probably. Code requires that junction boxes be accessible. But sine yours are accessible from the bottom, where the fixture is, that meets code.

This is more often a problem with just a 'junction' box, rather than one used to attach a fixture. That still has to be accessible, not buried in walls or under floorboards in an attic. But it's fairly easy to do in a basically unfinished attic like this: you just saw off a foot or so section of the floorboard, attach a hinge at one end to make a sort or trapdoor, and (to be fancy) drill a finger-sized hole to open it. Then it can legally be under the floorboards, since it is accessible by opening that trapdoor.

Post a reply as Anonymous

Photo must be in JPG, GIF or PNG format and less than 5MB.

Reply choose button


Post new button or Login button