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#30083 - 10/04/03 09:47 AM recessed cans in drop ceiling  
mchimes  Offline
Member
Joined: Apr 2003
Posts: 15
Alexandria, VA, USA
Hi,

I have Halo "remodelling" cans (H99RT) that I want to mount in a drop ceiling. The tiles are Armstrong 1" nubby. The problem is that the cans are non-IC and say to keep the luminaire and box at least 3" from any insulation.

I can understand why Halo would say this as insulation could be set on fire by a spark from the fixture. So I tested the Armstrong's fire resistance. I cut a 3" x 3" square and held it over the blue flame of my stove. It performed extemely well. It would not catch or hold a flame, but would slowly turn brown and receed slightly quickly extinguishing itself. Given the performance of this product under such extreme conditions, would it really be hazardous to mount these cans or are such codes intended for other types of insulation that would combust upon contact with a flame or spark?

I am not going to mount these if they are unsafe. Period. But I don't see how the "new construction cans would fit this application.

So I have 2 questions:

1) What type of housing should mount into 1" nubby in a drop ceiling?

2) Is it really unsafe to mount these cans into the Armstrong nubby I've described or is it just a precaution by Halo to "cover their bases" knowing all the different types of insulation their housings may be installed next to?

Thank you,
Mike


Work Gear for Electricians and the Trades

#30084 - 10/04/03 10:10 AM Re: recessed cans in drop ceiling  
Trumpy  Offline


Member
Joined: Jul 2002
Posts: 8,211
SI,New Zealand
Gidday Mike,
Look I think that the only real issues that you may have with this sort of lighting is heat build-up, between the tile and the fitting itself.
With respect to the Insulation, as long as there is at least 4" of clear ventilation space(air) around the fitting, I don't really think that you can go wrong.
The only thing that sets roof voids on fire, is when insulation is put over the top of and close to these fittings(aka lack of ventilation!). [Linked Image]


Let's face it, these days if you're not young, you're old - Red Green grin

#30085 - 10/04/03 11:02 AM Re: recessed cans in drop ceiling  
mchimes  Offline
Member
Joined: Apr 2003
Posts: 15
Alexandria, VA, USA
Thanks Trumpy,

I am concerned about the heat build-up around the can itself and the hole (which will be a snug fit) in the fiberglass. I guess the fiberglass will be exposed to the outer surface of the can and the heat there. But wouldn't the smae situation exist with an IC-rated light can too? The hole has to be fit snug (not allowing 3" clearance)

The issue of insulation and ventilation is moot . . . this is a non-standard ceiling tile application for a sound studio. The ceiling tile array will not actually extend to the edges of the room and there will not be insulation above it . . . so plenty of air up there. The real ceiling is 5/8" fire-rated gypsum board which will be 2.5" from top of can.

So the concern seems to be the contact of can housing with fiberglass tile . . . any thoughts?

I saw what the tile did under a blue flame. I think it would be fine from the heat of a can (I could even use low watt bulbs) . . . but I'm not a pro.

Thanks,m
Mike


#30086 - 10/04/03 11:09 AM Re: recessed cans in drop ceiling  
mchimes  Offline
Member
Joined: Apr 2003
Posts: 15
Alexandria, VA, USA
OK . . . I did a test with some cans I have already installed into an accessable soffit. I held my fingers against the inside bottom of the can (right below the 50W bulb). The light has been on for 3 hours and is at it's operating temperature. After holding my fingers there for 1 minute or so, I would descibe the heat at that part of the can being that of warm-hot tap water . . . I could have held it there indefinitely.

So I then reached into the soffit and held my hand on the outer top part of the can (where the wiring bridge comes out to the box). I held it there for about 20 sec and it became uncomfortable. I would describe that heat as being that of very hot tap water . . . bearable but you wouldn't want to have to use it directly on your hands for more than a few seconds.

So those are the heat levels we are talking about, hope this helps.

Thanks,
mike


#30087 - 10/04/03 12:34 PM Re: recessed cans in drop ceiling  
Wirenuttt  Offline
Member
Joined: Nov 2002
Posts: 267
Massachusetts
Hi Mike;
I work at a supply house in Ma. I know Halo is a good brand can. We carry our own brand as well as Halo, Juno and Progress. The Elite brand cat# B6RIC-At is a remodel old work can that can be in direct contact with insulation and is also air tight for codes here in Ma. I'm not sure where you are, but we have supply houses all over.

Hope this helps
~Andy


#30088 - 10/05/03 04:12 AM Re: recessed cans in drop ceiling  
straightedge  Offline
Member
Joined: Mar 2002
Posts: 86
Mesa, AZ
Mike,

It kind of sounds to me that you are mistaking the ceiling tiles as insulation.

I am assuming that you are cutting a 6" round hole in the ceiling tile. Which is usually 2' by 4' square and 3/4" thick.

I understand that the ceiling tiles are sometimes made of insulation type material. When the recess can says NON IC rated, (Insulated Ceiling), they are talking about the insulation that goes above the ceiling tiles.

Just make sure that you push all of the above ceiling insulation about 4" away from your recess can like Trumpy posted.

Some recess can light fixtures have some sort of temperature limit switch. If you leave the insulation directly on top of the recess can, the light will turn off for about ten minutes then turn back on. It will keep repeating this untill you remove the insullation.

Tev


#30089 - 10/06/03 07:28 PM Re: recessed cans in drop ceiling  
HotLine1  Offline


Member
Joined: Apr 2002
Posts: 6,826
Brick, NJ USA
Mcchimes:
I have two (2) issues with your proposed installation:

"RT" cans are for "old work"......if you are putting cans in a drop ceiling, you need something like Halo H-7, with the mounting bars to support the can. The code says that the can has to be supported. THe bars on the H-7 type cans extend to fit the 2' spacing of the grid, and you would screw the bars to the grid.

The "white" part of the can is adjustable to the thickness of your ceiling tiles, if necessary.

Also, there are aftermarket mounting bars/rails that are designed for 2x4 grid ceilings.

The second issue is you are mis-interpreting the "insulation contact" wording. A "regular (non-IC rated) can in contact with thermal insulation will "cycle" due to excessive heat "tripping" the thermal protector. This also happens when the inproper wattage bulb is installed in the can, dependent on the trim chosen also.
The "TP" is mounted on the interior of the can, near the top.

PS: I referenced "HALO" numbers, but there are a multitude of mfg's of this style can.

John


John

#30090 - 10/06/03 08:05 PM Re: recessed cans in drop ceiling  
Ryan_J  Offline
Moderator
Joined: Aug 2003
Posts: 1,374
West Jordan, Utah, USA
The armstrong tiles being described sure sound like they are fire-rated. Are you installing these in a fire-rated horizontal assembly? If so, you will need to build shettrock boxes around them. Something to think about... [Linked Image]


Ryan Jackson,
Salt Lake City

#30091 - 10/07/03 05:06 PM Re: recessed cans in drop ceiling  
PCBelarge  Offline
Member
Joined: Jun 2003
Posts: 681
Dobbs Ferry, NY, USA
Ryan

The ceiling can have fire rated material, but not necessarily be required to be fire rated, therefore he can penetrate the fire rated ceiling without the 'firebox' being required.

Pierre


Pierre Belarge

#30092 - 10/07/03 06:07 PM Re: recessed cans in drop ceiling  
Ryan_J  Offline
Moderator
Joined: Aug 2003
Posts: 1,374
West Jordan, Utah, USA
Pierre, I agree. Sort of like unlimited area buildings that are "combustible construction" yet made out of masonry!

I just wanted to let the original poster aware of possibility. Thanks again.


Ryan Jackson,
Salt Lake City

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