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Joined: Oct 2002
Posts: 830
I have installed the 2 tube flange type flourescent light before, but I have a need of installing 6 four tube recess flanged type lights in sheetrock. The ceiling joist are 2ft. on center. I called my supply house and they said the dimensions were just like a "lay in light". Since the ceiling joist are 2 ft. on center, a full 24 inches wouldn't work unless this dimension is for the trim only, then the "body" of the fixture tapers off, so it will fit in between the ceiling joist. Has anyone installed these type before? Do they fit in between the 2 ft. ceiling joist?
Called another lighting place and they said the measurements were 23 1/2 X 48 1/2 . Surely they would make one that would fit in between regular ceiling joist. Thanks for the help. Steve.

Joined: Apr 2002
Posts: 7,333
Likes: 7
You hit a good point. We have put in a few over the years. They come in two parts, a frame, and the fixture body. Can't really say what the dimensions are/were exactly. We do all comm work, 99% is sheetmetal framing. 24" o/c framing usually has a rough 22-1/2" space. Catalog I have now says width 23-3/4"; mounting brackets fully adjustable over 3-1/4" range from within installed fixture. BTW, the 23-3/4" is the same as a 2x4 lay-in.


Joined: Dec 2004
Posts: 209
I've done this in the past with a Mobern Electric Corp recessed flanged 4 ft x 1 ft 4 lamp fixture. It fit betreen 16" oc joists and is flanged for the drywall. Model # RF121-440E (

Joined: Feb 2002
Posts: 375
It could be worse:

3-1/2" flanges on I-joists with 24" spacing only leaves 20-1/2".

Joined: Oct 2002
Posts: 830
Anybody know a picture and specifications on the web here anywhere. I went to Lithonia, but I can't find one in their catalog or on the net. I must be missing it somewhere. I really need to find some dimensions and specs before Monday if I can. The 1 X 4's that I've done in the past, came with the flange and body together, no adjustments. I guess the 23 1/2 spec's that I was given would squeeze into the 22 1/2 " opening if it wasn't for the sheetrock will already be nailed which will hold the ceiling joist secure with no "give". I'm guessing it will work, but would like to know for sure. I don't like the idea of "beating it in there" if you know what I mean. What's the good of having a fixture you can't use? You can't cut a ceiling joist legally and pratically [Linked Image] There's gotta be something I'm missing here somewhere.. Thanks again.. Steve

Joined: Jan 2003
Posts: 1,429
LK Offline
When we order this type of fixture, it usually takes 4 to 6 weeks to get them.

Try this site for more info on this type fixture,

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