Attic insulation after pot light installation
 

I've just installed 6 3" halogen potlights in our bedroom ceiling, above which is the attic. I'm a bit confused now as to how I need to properly insulate everything, to protect from heat loss and fire. We'll be blowing in new insulation into the attic as soon as I'm sure the lights are finished.

I bought metal boxes to house the light fixtures - same manufacturer, built for the lights. Each box is rectangular, probably about 6x12 inches, and maybe 6 inches tall, so about half a cubic foot. These were installed between joists with hanger bars, on top of the vapour barrier laid over the drywall ceiling. I then spray-foamed around the base of the metal boxes, and foamed in any gaps (unused knockout holes and around the wires entering the box). But I'm looking at them thinking the heat from the halogen lights could easily heat that box up pretty hot.

Am I being paranoid here? Will the heat dissipate fine in a metal box that size? Or should I box them out even further with plywood? I saw one video on youtube where they guy made boxes out of styrofoam and glued that together. Seems easier than plywood, if it's effective enough.

I'd be very worried about halogen lights in the ceiling with anything flamable around them. Definitely do more research on this.

Best to talk with the manufacturer and/or your insurance company....get any answers in writing. Insurance companies and sheep all LIE!

Christien,

You are good with this set-up. It looks like you've done everything right.

The fixtures themselves have air circulation holes in them (usually) so air will circulate. That's why you have the boxes to stop the air movement through your insulation.

Best
Les

You may also want to look at these. I replaced the 3 in my kitchen after I read the post below, and would happily recommend them. Not only do they work well, save electricity and put out nice quality light, but they should run much cooler and they look much better than the normal bulbs and bezels in most recessed lighting. The only downside is the initial cost, but if they last 15 or 20 years, that may not be that big a deal either..

Some people make an additional box (around the metal box) from drywall. Just cut the shapes and caulk it. Keeps the insulation away from the box.

Switch to LED bulbs and the heat issue disappears.

There are IC (insulation contact) and non IC. If your lights are IC you should be fine.
You mentioned vapor barrier laid over the drywall ceiling. I didn't think you wanted a vapor barrier above the drywall. ??

Only if you really don't want to see with the lights on. what do you do about spot lighting if you need to light up something?

Don is right, IC can are only allowed down here. Is it new construction or remodel cans? YOu call em' pot, we call it can.

Heat can be reduced with a special lamp that is coated in the back and the heat radiates from the front of the MR16 bulb. They are designed for that, so it will help.

Ugh, no LED. I hate them. Very little light, and what light there is makes everything look like a morgue. I don't use CF or LED lights anywhere except work surfaces.

The lights are non-IC. (never heard of that, but just looked them up).

The vapour barrier seems to be over the entire surface of the ceiling, below the joists. That would've been there when they built the house (1983) I'm assuming - we certainly didn't put it there.

It's remodel - cut holes in the bedroom ceiling, but installed the box in the unfinished attic.

Here are the lights and boxes I used:

Commercial Electric | Promotional Pack, (6) 3 In. GU10 New or Remodel Construction Housing Kit w/ (6) White Gimbal Trims with Bulbs Included | Home Depot Canada

EasyLite | Insulated Box New Construction | Home Depot Canada

See those gaps at the top of the box? They open into the chamber, so I filled them with expanding foam, as well as covering the unused knockouts with foam.

Yes IC is the ticket.

Yes New construction cans or remodel cans they are a little different.

I think you want to use the right ones even if you use the lower temp florescent bulbs in case some one put a standard tungsten bulb in them later.

Attic fires are the worst.

Yikes? Is that the slot on tho of the box? That might be your heat release vent. Those light put out lots of heat, so the heat must have somewhere to go if not, in time the metal box will get heated up just like if it wasn't there. If you are going through the trouble of installing the metal box, why not do it right (much stronger install, IMO because the light is screw or nailed to the framing instead of it hanging onto the drywall) and use a IC can since you are already in the attic.

Personally, I usually stay away from Commercial electrical lights. They buzz ad hum when dimmed. Do they have Nora lights up where you are?

I,m doing the same thing now. The 3 in pot is not ic rated but the square box light combo is . the lights also have a safety cut out switch which is heat activated. I would trim the vapour barrier back at leat 2 in from the box. There is a blue plastic high temp vapour barrier bag available at home depot.

A regular Mr16 bulb will not trip the heat switch, but on a Par 20 can, a regular 60 watt incandescent will because the way heat rises up into the can and trigger the switch.

Heat release? Ok, never thought of that. But if I leave it open, wouldn't insulation blow in there, when we blow it into the attic?

No buzz when they're dim, they're fine. Not sure if they sell Nora, I'll have to look.

cut a fiber glass square around each unit
that should keep the blow stuff out and away

I thought this was about something very, very different.

Tape it before you blow insulation in there. Go back in there after and pull tape off.

Nora is a great light, bang for the buck. Make sure you use the correct dimmer, check if its mag. or elec. transformer and use a dimmer accordingly. That will eliminate humming tremendously.

Lights and dimmer are already installed and wired. I didn't know there were different kinds. Guess I got lucky :)

I can't go back in once the insulation has been blown in - everyone's told me not to touch the stuff once it's been blown in, because it compresses and is then less effective. Blow it in and leave it - seal off the attic for good.

I don't know what to tell you about that because we don't use those boxes. We use IC cans doesn't matter what's up there in the attic. Its not worth the few bucks in saving, plus, they are screwed to the joist so it will never come off. You might be able to remove the lights and snake your hand in there and peel off the tape. Better yet, leave the hole and remove the light and vacuum out the insulation after its all done. Since they are remodel cans, it can be remove with ease. You gotta let the heat our somehow.

LOL! Me too.

I'm just going to build a box around them. Seems like the simplest and most fool-proof solution. A measuring tape, some drywall or styrofoam, a cutting knife and some adhesive and I'll have it done in less than an hour.

I assume insulation is mineral wool and as such, it's non-flamable
(otherwise, you couldn't have it on the attic ;) )

What's the wattage? I have 20W pots and they need less of a inch (19mm) free space above them to be "legal".

If using 10W, they don't need free space or pots.

I think you'll be all right.

how are you gunna get the pot out of the attic when it ready?:confused:

I think he meant no one goes in there unless it is absolutely necessary.

Well, harvesting the pot would be absolutely necessary :) I think he was playing on the joke. Maybe we should call them cans, not pots...

siht, I completely missed that one.

You need to be careful, as some lights are designed to work in insulation, and some are not. They do have thermal limiters now, but you have to make sure the ones you buy are the ones you need to use.

Did you not get a permit? If not if anything happens your insurance won't cover anything.

A permit for pot lights?

So did I.

If they are new wiring, then yes. Code will also dictate what you can and can't enclose

What? You do not smoke Can? :)