Fixture Supports

Status
Not open for further replies.
B

bgs1362

Member
Does the NEC require fixtures to be supported independently from the ceiling, (e.g ceiling wires to fixtures)? If yes, where?
Thanks for any clarification you can provide
 
Buck Parrish

Buck Parrish

Senior Member
Location
NC & IN
I think your talking lay in flourescents. Attached to the grid is probably a manufactor spec.
If independent tie wires are used the NEC requires them to be marked as different from the cieling tie wires.
I am pretty sure that tieing them independently is a building code in certain parts of the country.
 
B

bgs1362

Member
I'm referring to fixtures (fluorescent or others) that would be installed in ACT(drop) or drywall ceiling. I've had discussions with people debating whether the NEC requires an installer to provide independent supports for the fixtures (from decking or bar joists). These independent supports could be ceiling wire or cable.
 
jumper

jumper

Senior Member
Location
3 Hr 2 Min from Winged Horses
Buck Parrish said:
I think your talking lay in flourescents. Attached to the grid is probably a manufactor spec.
Click to expand...

This seems to say it is a NEC spec.

410.36 Means of Support.

(B) Suspended Ceilings. Framing members of suspended
ceiling systems used to support luminaires shall be securely
fastened to each other and shall be securely attached to the
building structure at appropriate intervals. Luminaires shall
be securely fastened to the ceiling framing member by mechanical
means such as bolts, screws, or rivets. Listed clips
identified for use with the type of ceiling framing member(
s) and luminaire(s) shall also be permitted.




If independent tie wires are used the NEC requires them to be marked as different from the cieling tie wires.
Click to expand...

I can not find that requirement.

I am pretty sure that tieing them independently is a building code in certain parts of the country.
Click to expand...

Yep. Also the manufacturer would have to state that the grid could support the fixture weight and they probably do not. I always independently support.
 
B

bgs1362

Member
I have read this also. Doesn't is say the fixtures must be supported to the framing member (framing member must be attached to building structure). The fixture itself is not required per NEC to be independently supported from the building structure. If you have a large project with a lot of fixtures, providing independent supports can be expensive if not required. This is why I brought up the question.
 
jumper

jumper

Senior Member
Location
3 Hr 2 Min from Winged Horses
bgs1362 said:
I have read this also. Doesn't is say the fixtures must be supported to the framing member (framing member must be attached to building structure). The fixture itself is not required per NEC to be independently supported from the building structure. If you have a large project with a lot of fixtures, providing independent supports can be expensive if not required. This is why I brought up the question.
Click to expand...

I believe, as stated above, it is a building code that deals with seismic zones. Also the grid manufactuer would have to state that that the grid would support all the extra weight, I doubt they will.

Every jurisdiction I have worked in-VA, NC, MD, CA- has required at least two independent wires on a diagonal support for lay in fixtures and such.
 
fishin' electrician

fishin' electrician

Senior Member
Location
Connecticut
jumper said:
Also the grid manufactuer would have to state that that the grid would support all the extra weight, I doubt they will.
Click to expand...

Every Armstrong (are there any others?)Grid System I have ever checked on listed fixture weight capacities between 40 and 70 lbs depending on grid layout.

They go on to say fixtures weighing more than 56 lbs should be independently supported. I'll venture a guess that most, if not all, 2x4 lay-ins weigh less than 56 lbs.:D

See page 4 of this document.
http://www.armstrong.com/common/c2002/content/files/8388.pdf
 
LarryFine

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
jumper said:
Every jurisdiction I have worked in-VA, NC, MD, CA- has required at least two independent wires on a diagonal support for lay in fixtures and such.
Click to expand...
Interestingly, while I've added support wires for cabling, I never have had to for lay-ins.
 
jumper

jumper

Senior Member
Location
3 Hr 2 Min from Winged Horses
fishin' electrician said:
Every Armstrong (are there any others?)Grid System I have ever checked on listed fixture weight capacities between 40 and 70 lbs depending on grid layout.

They go on to say fixtures weighing more than 56 lbs should be independently supported. I'll venture a guess that most, if not all, 2x4 lay-ins weigh less than 56 lbs.:D

See page 4 of this document.
http://www.armstrong.com/common/c2002/content/files/8388.pdf
Click to expand...

I stand corrected, they do give the data; however, look at the spacing of the support wires around the fixtures on that page. 4 wires, one on each corner of a 4 foot square around the fixture.

I would have a hard time getting the grid guy to add all those supports for me unless there was a lot of beer or cash involved.:grin:
 
jumper

jumper

Senior Member
Location
3 Hr 2 Min from Winged Horses
LarryFine said:
Interestingly, while I've added support wires for cabling, I never have had to for lay-ins.
Click to expand...

I can only say that the last two jobs I did up your way were in Ashland and Chesterfield Co. We put in support wires.

Maybe there are times when they are not required, I dunno. I just stick them in regardless. Too much effort for me to figure out when they are required or not. Inspectors seem to like seeing them, so it is worth it to me.
 
Status
Not open for further replies.
Top