air sealing
Eska
| Posted in Energy Efficiency and Durability on
how best to maintain air barrier at insulated ceilings when installing LED pot lights
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This depends a lot on what kind of LED lights you're using. If you're using LEDs in recessed cans, or any of the "conversion kits", then all the same issues apply to that recessed can as it would have before. If you're using the puck-type lights, it depends on the mounting. I like the lights that mount in 4" round electrical boxes. When I use this style of LED light, I use the white fiberglass "hard boxes", in part because they don't leak -- thay have no holes (or at least they used to not have any, more on that later). I air seal the perimeter of the box to the drywall, by cutting the hole for the box with a hole saw that leaves about a 1/8" gap between the box perimeter and the drywall. I fill the gap with canned foam using a gun and the narrow "injection nozzle" attachment (this is with the Dow foam gun). I seal the wire entry to the box with red silicone high-temp caulk, or sometimes with canned foam if I have good access to the back of the box.
The white fiberglass boxes are easiest to air seal. If you're using a surface-mount puck light, I don't really have any hints since I haven't used those before.
A note on the newer fiberglass hard boxes: I've noticed that the holes for the cover plate screws to thread into now go all the way through the box. I air seal those with a bit of canned foam on the backside. You can smear some caulk into the holes from the front of the box after installation too. Easy enough to do, but I didn't notice those holes now go all the way through until I happened, by chance, to see a worklight in the attic through the screw holes in a recently installed box.
Bill
Hey Bill - would you happen to remember the model of 4" LED light that mounts in the 4" round box?
thanks from Idaho!!
I used LED lights that mount into the round J- boxes. Specifically, I used the Nicor brand SureFit model. VERY happy with them. Mine are the gen 2 version, and I believe they are now on gen 5. The lights have been VERY reliable, they are efficient, and have a high CRI. They are dimmable with both leading and trialing edge dimmers. The trim comes in various colorsa nd the fixture is moisture resistant, so I used it inside all over including in the shower, and outside. The company has great customer service also - I had one fixture with a manufacturing defect on the trim, and they sent a new trim.
I ended up using them everywhere - closets, crawl space, etc. That way if one of a group in a public area burns out, and I can no longer procure a match, I can take one from the crawl, or a closet to replace the burned out one, and use something else in the crawl or closet.
They now even offer a wall wash, which was not an option when I ordered. They are also now higher CRI, more lumens/watt, and color selectable... Really awesome product. I'm just a very happy customer; I don't work for them.
https://nicorlighting.com/product/surefit-dlfv5-ultra-slim-surface-mount-led-downlight/