Seal Recessed Can Lights
Apr 14th, 2009 | By Greg Primm | Category: Air Leaks, Lead, Low Cost Tips
Recessed can lights are a popular item in newer houses. They offer good light with a sleak look to any decor. The problem with these fixtures is that since they are recessed, a hole has been cut into the ceiling for each fixture. This creates a pathway for air to infiltrate the hole. Even after the fixture is installed, there remains a small gap between the fixture and the sheetrock.
During the summer, cool air from the house is sucked up into the attic. This causes your house to constantly work to keep the air temperature consistent.
One major mistake I made while designing our current house is installing too many recessed can lights. In all, I personally installed and wired 48 of these beauties. Yes, you read that right — 48 recessed can lights, each one potentially providing a route for air to infiltrate my house.
The solution? Obviously install fewer can lights!
Too late for that? OK, you can seal the gap that remains between the fixture and the sheetrock. Here are the steps:
- Make sure the lights are turned off and cooled down.
- Remove the light bulb and then carefully remove the trim surrounding the light fixture. This could be a little tricky on the first few lights, but you’ll get the hang of it.
- Use caulk for smaller gaps and foam sealant for larger gaps.
- After the caulk or sealant cures, use your hand to check for air leakage.
- Replace the fixture trim and bulb.
- You’re done.
By reducing the amount of air leakage, you seal your house much tighter and make it much easier to keep the house cool in the summer and warm in the winter.
Photo credit: Thomas Hawk
I also put in @ 45 of these lights in my remodel and am wondering if I did wrong?
One question: I have only the housings minus the trim and bulb in but I don’t see any gaps between the housing and the sheet rock…..because the housing lip overlaps the edge of the sheet rock hole? However my AC is running constantly and their must be air going up….possibly thru the housing itself?
Does that mean I need to build a box in the attic around each can? My lights are IC rated Cooper Lights sold at Home Depot.
Thanks for the comment.
Most likely you still have some air leakage even if your housing is a tight fit in the hole in the sheetrock. You could try to use caulk around the seam between the housing and the sheetrock.
Yes, air can leak through the can itself. Many can lights I’ve installed in the past have holes in them where air can leak through. One thing I’ve done on past remodels is use duct tape (the good shiny kind for use on air conditioning ducts, not the dull gray stuff you use around the house) to cover the holes.
In my current home, we built boxes out of foam insulation board, taped together with duct tape (good stuff) and placed them over the top of the can. You can then use foam sealant to seal it in place. That should prevent the majority of air from leaking into your attic.
One last thing, be sure to check other places where this “chimney” effect could be taking place.
Disclaimer: just for full disclosure — I’m not a licensed electrician, so be sure to check with one if you have any questions about your specific situation. Can lights are capable of overheating. If you are using IC rated lights you should be fine, but don’t hesitate to ask questions of a professional.