Convertible IC-Non IC recessed old work cans. Can they be sealed?
The label on the can says Convertible IC- Non IC… Apparently categorization depends what trim kit is used and what wattage bulb is used. These lights have simple trim and use CFL indoor spots.
I’d like to seal them with foam before I blow cellulose. Then I can see myself having to change out the cans because the thermal switch gets activated. I’m on a ladder in a kitchen with the light can in my hand and 16″ of cellulose is pouring out of the ceiling, then the door opens, it’s a windy day and the wet puppy comes in, runs through the cellulose and down the hall to the bedroom where the infant with respiratory problems sleeps…….
Well the question is: Can I cover a convertible IC Non-IC can with foam if it has a 12 watt CFL in it?
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Didn't you just answer your own question?
It makes no sense to install recessed lights in an insulated ceiling, besides the fact that can lights cannot provide the same dispersed light per watt of a ceiling fixture. They are useful only in very limited applications for task lighting, such as in a kitchen cabinet soffit over a sink.
Walter,
Your question is unclear.
I don't think it's advisable to install spray foam directly against the back of the can lights. Instead, construct a box out of rigid foam, leaving a few inches of air space between the can light and the box. Seal the seams of the box with canned foam or housewrap tape. Then seal the box to the drywall, working from the attic. Now you are ready to blow cellulose.
I guess I did answer my question. The lights are already there. I think I'll suggest replacing them w old work air tight IC cans and seal to sheet rock with caulk. That should make it air tight, and let me sleep.
We've had great luck with 12" round duct. We cut the duct into 2' sections and cap them at the top. The supplies are readily available in the duct section at your local supply house. Simply assemble an 18-24" inch section of duct with a cap on the top and install over the can light. You'll have to use a pair of snips to relieve the duct anywhere there's an electric cable, light support, rafter etc... Clean the drywall ceiling and foam the duct into place. Foam around wires etc.... Bada Bing! This creates a reliable dam around the light while cutting off air flow. A little heat is allowed to escape the top of the duct so your heat switch won't trip and a 24" section will be long enough to go from kitchen soffit to top of insulation. This saves us loads of time with air sealing and is a much easier sale than radical lighting changes. Having said all of that: can lights suck and should not exist.
That leaves it this duct cap uninsulated. What good is that?
I can see several reasons to leave the cap exposed.
1) Access to the fixture in the future.
2) To prevent the thermal overload on the fixture from tripping (as mentioned above). A non-IC fixture can trip out if it gets too hot. A good example would be an incandescent fixture that cycles on-off every few minutes when overlamped (i.e. 100W in a 60W fixture).
Nathan,
Air leakage through recessed can lights is a serious problem. Because of the stack effect, the conditioned air near an insulated ceiling is under positive pressure, eager to find a hole and escape into the attic or rafter bays. That's why recessed cans are always a bad idea in an insulated ceiling.
If you want to address the problem, it makes little sense to adopt a halfway measure. If you are building a box around a recessed can light to act as an insulation dam, then the box needs a lid to prevent air leakage.
Some non-IC-rated cans will indeed get too hot if they are enclosed in a small box. The larger the box, the less likely they will overheat. Of course, it's always possible to replace an existing non-IC-rated can light with an IC-rated can light -- or, better yet, to replace it with a surface-mounted fixture like track lighting.
Yeah, cans suck in an energy efficiency kind of way, But they look great. Boxing them out with rigid insulation is a good Idea if you still want the recessed light aesthetic.
Look great?
I would argue that they are the ugliest of all possible lighting options, and a vestige of 60s modernism.
They also provide very poor area lighting, requiring several cans where a single ceiling fixture (with an almost infinite variety of aesthetic choices) will suffice.
They make sense only for limited task lighting, such as in kitchen cabinet soffits over a sink or counter.
If the customer loves recessed lights - then I love them too. Just smile and box them out. Eventually there will be a LED trim kit that the customer will love.
Martin to clarify my earlier statement, I did not mean that the cap would be unsealed, just exposed so the fixture could be located for servicing and to help remove excess heat.
Robert: I would agree that a can fixture is not the best for lighting in a residence where the (typically) darker floors, walls and furniture reduce reflected light from the fixture. In that situation a fixture that can direct light towards every surface is required. However I would not consider them "ugly", just misapplied. Unless you are talking about the cheapest residential grade lighting fixtures. Those ARE ugly.