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#200609 04/10/11 11:24 AM
Joined: Jan 2005
Posts: 5,316
Cat Servant
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The question is: MUST you use troffers ("lay in fixtures") to provide light through a suspended ceiling?

I recently saw a home with a finished basement. A suspended ceiling was installed. for lighting, ordinary strip fixtures were installed to the 'hard' ceiling above, and lens panels were put in the grid underneath the fixtures.

(I always wondered why I always had to trim the home-center lenses a bit!)

Details of this specific installation aside, it made me wonder if there was anything wrong with the very concept.

2017 / 2014 NEC & Related Books and Study Guides
Joined: May 2005
Posts: 984
G
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Every home that I've seen has been done with striplights and a plastic panel below. It's pretty easy to see the unevenness of the light from above...I wonder if that's because the manufactured troffers do a better job of spreading out the light before it hits the lens.


Ghost307
Joined: Jan 2004
Posts: 1,507
G
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Not sure I'd do it in my home. I don't see it as a code issue unless they were cord and cap connected. I have seen "cost conscious" versions of this that also include a reflector that almost fits the 2x4 space in a standard drop ceiling grid.

Last edited by George Little; 04/10/11 02:05 PM. Reason: typo

George Little
Joined: Apr 2002
Posts: 7,283
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I have to agree with George. You may find a 110.3 IF there is any indication from the fixture (luminaire) mfg that the fixture is designed for surface mounting.

That may be considered 'pushing the envelope' but....ya never know.


John
Joined: Jul 2004
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G
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I did this on an addition in my old house in Md (late 70s) and I would not do it again. I learned a lot of lessons on that project wink

The reason you have to trim the panels is they are actually 2x4 and the grid is 2x4 on center. You are trimming off the thickness of the T bar. YMMV it seems, some seem to be a tad smaller than 2x4 and go in without trimming.


Greg Fretwell
Joined: Apr 2002
Posts: 7,283
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Greg:

I think Reno was refering to using 'big box' lenses as replacements for 2x4 troffers. Basically, something that I can say 'been there, done that'!

Yes, I also had channel strips, with 'custom cut' lenses in our old house. And, I will not do that again.





John
Joined: Nov 2007
Posts: 763
K
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Iíve seen that type of install a lot over the years, especially in older 1970ís kitchens and basements. I'm wondering if the manufacture states surface mounting only as mentioned, since the manufacture most likely doesnít specify what particular surface is approved for mounting, I'm guessing that the suspended ceiling still wouldn't qualify as structural ceiling in this situation.

Joined: Jul 2004
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G
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I am just talking about screwing a strip on the structural ceiling above the center of a 2x4 T bar hole and dropping a diamond molded lexan panel in there instead of a ceiling panel.


Greg Fretwell
Joined: Feb 2008
Posts: 193
S
Member
I wired a tree house for a family and they wanted me to pick out a fixture that would be safe and fitting for their kids. I hate picking out fixtures for somebody else. I ended up put strip lights between the ceiling joists and framed in a slot for a panel to slide in below the joists. I ordered a panel with the clouded sky printed on it. It looked pretty cool in the tree house, like a hole in the ceiling.

Joined: Jan 2004
Posts: 1,507
G
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Hey Schenimann- Did you get a permit, an inspection and a C of O? ha ha ha


George Little
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