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mark petty
04-11-2013, 07:08 PM
This is a doctors office with drop ceilings and standard 2' x 4' fluorescent lights. Fiberglass batt insulation has been installed but not over the light fixtures. My question is: can the batts be laid over and on top of the fixtures. Thanks

Rick Cantrell
04-11-2013, 07:19 PM
I would think, no.

Jeff Langhorn
04-11-2013, 07:40 PM
Light fixtures that could come in contact with insulation would designate whether they are able to come in contact or not. IC or nonIC. That particular light fixture is used in drop ceilings where insulation is not able to contact. What do you think?

Dwight Doane
04-12-2013, 04:21 AM
If that's an unheated attic space I would think that the energy code would require insulation on top of that fixture.



Only if the fixture was designed to have insulation placed directly over it - otherwise the fixture could overheat and start a fire (part of this depends on how old the fixture really is - in a practical sense not code). If in doubt - I would always err on the side of caution and safety - some fixtures have [or had] components that would heat up and use the metal enclosure to dissipate heat - it could be that this fixture (and you will not know unless you go to the manufacture and check) it needs to be exposed or have a minimum clearance - Today's code (or code sections) can not be blindly applied when dealing with older building(s) - as you might be doing in this application.

Richard Burkard
04-12-2013, 05:55 AM
The manufacture of the 2x4 flourecent installation instructions may forbid insulation or combustibles to be placed directley on top of the lights. The tranformer may give off to much heat. I have seen flourecent light transformers melt.

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The manufacture of the 2x4 flourecent installation instructions may forbid insulation or combustibles to be placed directley on top of the lights. The tranformer may give off to much heat. I have seen flourecent light transformers melt.

Phillip Norman
04-12-2013, 07:49 AM
Any light so hot that insulation over it is not permitted, is a far bigger waste of energy than that from missing insulation. Effort should go toward inspiring light replacement with LEDs. Then fix the insulation.

LEDs are affordable now, and are generally rebated in commercial installations. The new lights will be pay for themselves in two to five years. Where else can a business earn such an investment return?

Robert Rolleston
04-12-2013, 12:19 PM
I would recommend the buyer install more efficient light fixtures and insulate above them. I would not make a seller make changes to meet new code.

Jim Port
04-12-2013, 03:41 PM
I have never seen one.

Robert Rolleston
04-14-2013, 07:00 AM
Anyone have a code reference or listing requirment that states that this specific type of fixture cannot have insulation on top of it?

Not sure about the fixture in the picture. But I had some T5 lighting that would get really hot. Actually had ventilation holes on the hop.

Larry Morrison
04-15-2013, 03:42 PM
The ballast on these lights can get very hot and most of the time if the insulation is put over them they will shut down or burn out....and even start a fire. Couple that with the "oil soaked" Kraft faced insulation, and you have an accident that could have been avoided. No I would never cover these type with any kind of insulation.

Daniel Mack
04-15-2013, 07:35 PM
Must be listed for the installation

I will have the specific NEC reference posted for you tomorrow.

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Must be listed for the installation

I will have the specific NEC reference posted for you tomorrow.

John Kogel
04-15-2013, 08:17 PM
They're doctors. They can pay the heat bills or they can buy new lights. The guy who did that installation thought better not cover those fixtures, why?

Larry Morrison
04-15-2013, 08:54 PM
They're doctors. They can pay the heat bills or they can buy new lights. The guy who did that installation thought better not cover those fixtures, why?
I'm guessing it was an insulation contractor that knew enough not to cover them and then be liable for a fire or at least a call back to uncover them when the ballasts craped out. I have been an Insulation contractor for almost 30 years and I would not cover them. I'll give you odds that they are not (Labeled) IC rated and if they are not, The standard by what an insulation contractor would go by is..."give the heat producing device 3 inches of clearance and also do not install insulation in a manner that would entrap heat". During the 80s these types of lights were very common, especially over the kitchens. Most of the time they had a box framed over them. Even with the box they were shutting off similar to recessed cans, or the ballasts were overheating and some were even leaking oil (making a nice mess). The standard fix was to cut a 3-4 inch hole in the top of the box and install a metal duct to vent the heat. sure you can mount these flush with a drywall ceiling where they have some breathing room at the sides and not have a problem but recessed into a ceiling where the sides as well as the top are covered, they will probably over heat.

Garry Sorrells
04-16-2013, 03:54 AM
Sorry if I missed it along the way.

The fixture has to be rated by the manufacture and typically certified by Under. Labs. for contact with insulation. If not certified for contact then no contact, no mater what code said.

There may be a way to box over the fixture so there is something holding the insulation off of the fixture, but that would depend on manufacture specifications for installation.

Robert Rolleston
04-16-2013, 03:59 PM
Must be listed for the installation

I will have the specific NEC reference posted for you tomorrow.

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Must be listed for the installation

I will have the specific NEC reference posted for you tomorrow.

Code referance and year it was added usually helps to determin whether it applies to when this work was done.

Daniel Mack
04-16-2013, 07:51 PM
The specific code sections are:
NEC 110.3 B listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.

NEC 410.116 (B) Installation. Thermal insulation shall not be installed above a recessed luminaire...unless ...identified as type IC for insulation contact.

Jim Port
04-17-2013, 04:48 AM
That is not the type of fixture I would think of if you said a recessed light or luminaire.

Phillip Norman
04-17-2013, 06:30 AM
There is more to be said about the insulation. It has near-zero R-value. Where insulation is not in contact with a warm surface, air is driven in convection, with nearly the same velocities as if there were no insulation present. The steel grid randomly holds the batt kraft facing in line or point contact. The batts are not in contact on edges, and heated air freely rises and falls to equalize all attic air temperature.

Do you believe me? The proof, or not, is simple. Let's just look at HVAC operating cost with and without such poorly-places batts in a few offices. A Google search of terms "batt insulation over suspended ceiling" (https://www.google.com/#hl=en&sclient=psy-ab&q=batt+insulation+over+suspended+ceiling&oq=suspended+ceiling+insulation+batt&gs_l=hp.1.1.0i22i30j0i8.1479.12811.0.24385.33.20.0 .13.13.0.163.1453.19j1.20.0...0.0...1c.1.9.psy-ab._iet71RCrko&pbx=1&bav=on.2,or.r_cp.r_qf.&bvm=bv.45368065,d.cGE&fp=f7c94c94be7e2a1&biw=1246&bih=690) finds some good discussion. Putting batts on the grid is rarely done, and fruitless.

This is a matter for global energy policy, not for the inspector's report. Researchers taking responsible action must consider the leakiness too, of the grid. An air-tight barrier is needed to avoid energy loss in movement of conditioned air to/ from the attic and the outdoors. As we repair this mess in a national campaign to use LED lighting, we will need to invent new entire ceiling systems for offices like this. I wonder what the LED lights will look like. I bet they won't be the rectangles or squares of the fluorescent lighting. Down light spots a couple of inches diameter, I bet. A starry sky in low-voltage DC wiring.

Policy will need to deal with renters interests too. The doctor here will do right, handed a solution. What of the building owner 2000 miles away, and his tenant business owner paying the utility bills?

H.G. Watson, Sr.
04-17-2013, 09:22 AM
Not all "drop ceilings" are equal. Listed & rated systems have their own requirements. Appropriateness starts first with the function of the drop ceiling and if it is providing function of resistant construction (protection of truss system, separation of occupied space).

Assembly or listing for the ceiling system, the Standards for Safety regarding the lighting system, the listing to wit, manufacturer's instructions, and a multitude of other considerations regarding the overall construction, what is and is not in the space, and if there are specific care/treatment/equipment areas in the suite areas below.

Generally, as what is depicted as appears as installed is not rated or listed for IC nor direct contact and requires free air space.

Jim Port
04-17-2013, 10:16 AM
According to Lithonia Tech Support, the only difference between a standard GT8 troffer and the IC troffer is a sticker. I did not call others to see if they were the same.

H.G. Watson, Sr.
04-17-2013, 11:18 AM
According to Lithonia Tech Support, the only difference between a standard GT8 troffer and the IC troffer is a sticker. I did not call others to see if they were the same.

Commercial not residential for one, there are a host of listing marking requirements & again it depends mightily upon the classification, function, construction, and purpose of the assembly it is recess-installed into as well! Rated assemblies have their own specific requirements.

either appended in your UL White Book (Guide) or freestanding UL Marking Guide for Luminaires. (Despite file name is current to NEC 2011). UL 1598.

Luminaire Product type specific index for Fluorescent Recessed Mounted Luminaires
Category Code Guide Designation: IEVV
Product specific Index at pdf doc page numbers 11-13 of 36 (marked pages 9-11), the notes referenced begin at pdf document page 27 of 36 and continue to and through the last pge (36/36).

Jim Port
04-17-2013, 12:23 PM
Are you saying there are troffer fixtures only for use in a residence and not to be used in another type occupancy?

H.G. Watson, Sr.
04-17-2013, 05:29 PM
Are you saying there are troffer fixtures only for use in a residence and not to be used in another type occupancy?

I am not saying anything even remotely akin to your suggestion.

The OP's topic has nothing to do with a residence.

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Are you saying there are troffer fixtures only for use in a residence and not to be used in another type occupancy?

I am not saying anything even remotely akin to your suggestion.

The OP's topic has nothing to do with a residence.