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Recessed Lights Are Evil

By In Recessed Lights On February 1, 2011


I love recessed lights, but even the best ones create a ridiculous amount of heat in attics, which can lead to ice dams.  Until I started performing infrared inspections in attics, I never quite grasped how much heat recessed lights contributed to attics, but now my eyes are wide open.  The main problem I find with recessed lights is that they’re not insulated well enough; on a recent home inspection in Maple Grove, I found a home with forty-six recessed lights sticking up in to the attic, along with some wicked ice dams on the roof.

A standard recessed light will stick up in to the attic about seven inches.  If an attic has fourteen inches of  loose fill fiberglass insulation, how much insulation does that leave on top of the recessed light?  Hang on, let me get my calculator…

At any rate, there’s far less insulation above recessed lights than anywhere else in the attic, and these are the areas that get the hottest, so they should really have more insulation than anywhere else in the attic.   Unfortunately, that never happens.  The combination of minimal insulation and hot light fixtures shows up clear as day using an infrared camera.

Recessed Light in attic with IR overlay

The images above show how much heat is leaking through the insulation above an IC rated, airtight recessed light with a 65-watt incandescent bulb.  IC rated means that it’s safe to have insulation directly in contact with the light, but it’s not synonymous with airtight.  You can usually tell if a recessed light is airtight just by looking inside it; if there are a bunch of holes inside the housing, it probably isn’t airtight.

Non-airtight recessed light

If you can see light pouring through on the attic side, it’s definitely not airtight.  All of these little holes in the housing are passageways for heated air to escape in to the attic; they’re called attic bypasses.

Non-airtight recessed light

Having said all this, I don’t think recessed lights are truly ‘evil’, but they sure can cause a lot of problems, and there seems to be very little understanding of this in the building trades.   Here’s what you can do to prevent problems:

If you plan to install recessed lights that are going to protrude in to your attic, make sure they’re airtight, IC-rated lights.  After the lights are installed, be sure to double down on the amount of insulation above the lights; you’re gonna need it.

If you already have airtight recessed lights in your home, you probably need way more insulation installed on top of them.  This is usually quite simple to do, but without an infrared camera, it might take a little time to locate all the lights.

If you already have non-airtight recessed lights sticking up in to your attic, don’t worry; there’s a fix for this.   Simply construct an airtight box out of rigid foam insulation, and ‘glue’ it together with spray foam.

Insulated Box

Now place this airtight box over the offending recessed light in your attic, and use a bunch more expanding foam to seal it up and make it completely airtight.   Not only will this prevent air leakage from around the light, but it will dramatically increase the insulation level above the light.  While the box pictured below is the ugliest box I’ve ever seen (I built it), it’s still very effective at preventing heat loss.

Insulated box over recessed light

If constructing and installing insulated boxes throughout your attic seems like too much work, you could always replace any standard incandescent light bulbs with compact fluorescent lights or LEDs; they produce far less heat, they’re easy to install, and you’ll start saving money on your electricity bills.

Reuben Saltzman, Structure Tech Home Inspections – Email – Maple Grove Home Inspections

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About the Author


Reuben is a second generation home inspector with a passion for his work. He grew up remodeling homes and learning about carpentry since he was old enough to hold a hammer. Reuben has worked for Structure Tech since it was purchased by Neil in 1997, and is now co-owner and President of the company.


  • Elie 3 YEARS AGO

    Excellent. Much appreciated and Happy New Year.

  • Justin 3 YEARS AGO

    Hi Reuben, Thanks for your post's, very informative and appreciated. I have a multitude of recessed lighting issues I am dealing with. In my upper level of our ranch home we have 64 recessed lights. Some going into the attic with room to build boxes and some so close to the soffet or on on the outside (corner of the house) of a tray ceiling - virtually impossible for a human to get access to this space with our 4/12 roof pitch. I am converting to the Cree LED 6.0 W 40Watt equivilant on some and most to the LED 9.0 Watt 60 watt equivilant as in Connecticut we get a great deal on the energy efficient lighting through a state program. That said, I have tested temperatures inside the recessed lights and they have come to only 95 F - I have tested with the fire-block greatstuff by completely encapsulating a couple of my IC rated 7'' hats with amazing success - I did this in an open area as my thought is to try and do this to some extent on the inaccessible ones from the living space with strategically placed holes around the existing ceiling penetrations. So - my questions for you are about foaming directly to the IC rated hat with the aforementioned fire-block type foam - I know it is not fire proof but is it in fact more fire resistant and withstand temps in the neck of the woods I should be concerned with? Thanks again for your comments and input! Justin in Connecticut

    • Reuben Saltzman 3 YEARS AGO

      @Justin - my guess is that you'd be fine, but it's definitely just a guess. If you want an official answer, you'd probably need to contact the spray foam manufacturer, the light bulb manufacturer, the light manufacturer, and the Mythbusters.

  • Elie 3 YEARS AGO

    I am finishing a basement. i have IC-rated cans in the ceiling. i am trying to sound-proof the room as much as possible, and was thinking of building a box of soundproof drywall over the top of the cans (i have QuietRock). There is not much clearance between the top of the cans and the floorboards above. There is probably just enough to build the drywall box and then put 3" insulation above the box. The question is, is there any fire risk (or other problem) if i build a box of quietrock with just maybe about one inch clearance above the top of the IC can?

    • Reuben Saltzman 3 YEARS AGO

      @Elie - if they're IC rated lights, no issue.

  • Yask 3 YEARS AGO

    Hi Reuben We have recently installed LED recessed lights that does not require insulation box. We are unable to access the attic area (split level home) so electrician put holes in the ceiling from the house to fix the lights. Now we are facing increase in the Gas bill for heating. We compared last years bill to compare this year's bill and its higher why is it so? please guide.

    • Reuben Saltzman 3 YEARS AGO

      @Yask - If you're experiencing higher heating bills, it's probably because the cost of gas went up or outdoor temperatures are lower this year than they were last year. Installing a few recessed lights wouldn't make a noticeable difference in your heating bill.

  • Pam 3 YEARS AGO

    I have 10 Halo can lights from 1987 that are in my attic and light the bedrooms of the top floor. I have a problem with insulation debris coming down through them as well as ten perforations into my attic. They are not IC or AT and I would like to make them both so I can put insulation over them. I would also like to put LED bulbs in them. I have already put LED floods in the cans in my kitchen and am very happy with the light there. But, do the new cans come with a socket that works for LED bulbs. It looks like the new Halo 6" cans (HALO H71CTWB 6" air tite) on Amazon talk about incandescents. I assume this is OK, but am not sure as the LED bulbs seem heavier. I don't want to go to all of the work of changing to new cans and then not have them be right.

    • Reuben Saltzman 3 YEARS AGO

      @Pam - I see no reason why LEDs wouldn't work, but if you want to be 100% sure, check with the manufacturer.

  • Jesse 3 YEARS AGO

    Reuben, Years ago, I installed 4" halogen non-IC recessed housings in 3 rooms of my house. Originally, I made simple tin covers that kept the ceiling batt insulation away from the fixtures, after reading about overheating. Air leakage into the unconditioned attic space wasn't thought of back then, but it is now. I bought new ICAT low voltage MR16 housings, but due to compatibility issues with the trim rings, I'd like to return the ICATs and build either rigid foam or drywall boxes over the air-leaking non-IC existing housings. My concern is overheating the lamp/risk of fire issues. Can you comment on the use of self-made boxes?

    • Reuben Saltzman 3 YEARS AGO

      @Jesse - as long as you maintain the required distance from the light, you shouldn't have any problems with overheating / fire issues.

  • Love MN Winters 3 YEARS AGO

    I've been planning on upping the insulation in my attic from R-30 to R-49/60. In anticipation of this I started looking at the 4 can lights I have in my living room. They were not IC rated so I replaced them with 5" IC rated cans. We're going to blow in the new cellulose this weekend so I wanted to test how the IC rated cans were doing with the current insulation levels I have. I turned them on for several hours and then went up in the attic to see how hot they were. While they didn't burn my hand, they were very hot to the touch. Should I be concerned about this? Will the addition of 10" of insulation on top of the cans make the problem worse? I was debating building a box around the IC fixtures just to be sure I didn't have any issues in the future.

    • Reuben Saltzman 3 YEARS AGO

      @Love MN Winters - no, this isn't something to be worried about. Recessed lights with incandescent bulbs get very hot to the touch. It's normal.

  • Carl 3 YEARS AGO

    Thanks very much, just built 4 of these for the Bazz Cube lights I installed, but cannot use a standard mounting box for to protect them from the insulation. This will also keep my R value up, so you've done me a double service as this cost me a total of 40 dollars, with enough for at least 2 more boxes.

  • nick 3 YEARS AGO

    hi, i installed 6" commercial electric can lights in my basement. they are rated for 65 watt incandescent BR30 bulbs according to the sticker on the can. So i put a 65 watt flood bulb in each can but these seem too hot and are melting the baffle/trim. whole basement smells like melted plastic. what gives?

  • Kevin 4 YEARS AGO

    Good information. I have non IC 6 inch pots. I like the foam or drywall boxes and keeping it 3 inches away.....however is that only if fixtures have a safety switch as some non IC do.

  • ryan 4 YEARS AGO

    I want to install 4w and 7w leds on the 2nd floor ( the ceiling is insulated). the leds have a heatsink that goes in the ceiling. do i need to make a box around the led? or move the insulate away from the led or just place the insulated over the led? P.S I live in canada it does get pretty cold

    • Reuben Saltzman 4 YEARS AGO

      @ryan - I recommend you consult with the manufacturer of the light that you're installing the bulbs in.

  • carey 4 YEARS AGO

    that's all great that every one wants to use sm foam and spray foam but you have to remember that it is a combustible. and if anything you should be using is 5/8 type x drywall and fire stopping . just saying . there are fire codes to think about.

  • Kirk 4 YEARS AGO

    I knew a man who had recessed lights in his kitchen. After a half hour they would go on and off by themselves. They were cycling on the thermal protector in the housing. Fixing the problem required removing the insulation for 6 inches around the can.

  • Charlie 4 YEARS AGO

    Abigail Putnam: I just want to put my two cents in. I live in MN. Although we do not have cathedral ceilings, we have sloped ceilings that get down to less than a foot of clearance between the ceiling and the roof in spots. What I did was use low profile, airtight, IC rated cans (much shorter than standard). On top of that, I picked LED recess kits. They contain the trim and bulb in one unit, and they look fantastic.The ones I used were "Commercial Electric", there are many other brands. I wonder if Reuben would grace us with his take on that combination, IC, Airtight, Low Profile cans along with LED kit. Very low heat, 11 watts per light.


    Hello Rueben, I have three non IC rated recessed lights. What is the best way to air seal those? or should I put IC rated lights in attic and then air seal? What would be safer and cost effective approach?

    • Reuben Saltzman 4 YEARS AGO

      @KK - The safest and best way to air seal and insulate would be to replace the lights with IC rated airtight lights, and then install insulated boxes over them. The most cost effective approach would be to just install the insulated boxes.

  • Abigail Putnam 4 YEARS AGO

    Thank you for the advice. We live in Massachusetts; so yes, similar to Minnesota. We are not sure what we will do for lighting in the shower, but we will completely avoid recessed lights. Thank you!

  • Abigail Putnam 4 YEARS AGO

    Hi Reuben, This post was very informative for us as we are renovating our home. Our challenge is that our home is old with very low ceilings. For our master bedroom and bath, we ended up eliminating the attic above that half of the house, to create a cathedral ceiling. Thus, the ceiling in these 2 rooms is the actual roofline. We were warned that we should not put recessed lighting in these rooms because of the production of heat. Do you think your insulated box suggestion would work in these spots? Or would the LED lights be ok? Or should be completely eliminate the idea of any recessed lighting in these rooms and go with some other style? Thanks!! Abigail Putnam

    • Reuben Saltzman 4 YEARS AGO

      Abigail - where are you located? If it's anything like Minnesota, I'd skip the whole idea of putting recessed lights in your cathedral ceiling.

  • Reuben Saltzman 4 YEARS AGO

    @Neil - Who is Greg? If the insulation contains asbestos, you should either leave it alone or have it professionally removed / abated before doing work around it. Otherwise, what's the problem?

  • Reuben Saltzman 4 YEARS AGO

    @Paul - who is Greg?

  • Neil 4 YEARS AGO

    Hi Greg, I have recessed lights in my great room. Only 4 of the them, it's an open to above room. I find there is not enough light. So I am in the process of adding another 5 lights there. I am told by some that I should not disturb the insulation, and other's say there is no worries of adding more and no issue with disturbing insulation. what are your thoughts? thanks Neil

  • Paul 4 YEARS AGO

    Hey Greg, In the process of renovating my first home, it's a 2 storey century old home. I have the whole thing torn apart and have finally completed the demo phase and am begining my wiring. I have a flat roof spanning about 30'x14' the trusses are all true size 2x8. I have specd' out closed cell spray foam insulation for the entire home (including the flat roof) which will give me a value of R30 and leave me roughly a 3-3.5" gap between the finish insulation and the drywall. We plan on zero clearance pot light that will be wired prior to insulation being sprayed. Any thoughts on this? What if any are your recommendations for type/style or model or pot light? Since the house is fully stripped now is the time for me to do this properly and I want to make sure that I'm not over looking anything. Thanks, Paul

  • Charlie 4 YEARS AGO

    Hey Reuben! I read this article a little late. I had just installed 4 new construction, IC rated cans in my kitchen that were not airtight. I was just about to install 13 remodel cans that were the same, IC but not AT. I have a sloped ceiling, and there was maybe a foot of space above these cans and my roof.So I pulled out the new construction cans, returned the remodel cans, and got ones that were both airtight and low profile. I was going to go with CFL's, but they were pricey, looked terrible, and required special dimmers. I ended up going with LED trim kits, and I have to tell you, I couldn't be happier! The cost was about the same as a quality dimmable CFL plus a decent trim. Now I am using 117 watts vs. the 1275 I would be using with incandescent, and 408 I would have used with CFL! And they look GREAT, you would never know they were LED. Thanks for the article, I think you saved me a TON of time, aggravation, AND money!!! I can't imagine if I went ahead with what I had.

  • Craig 4 YEARS AGO

    We're looking into having more insulation blown into our attic (Oklahoma). We currently have 16 non-IC rated cans installed in our house. The main problem for IC-rated replacements or putting insulated boxes over them for me is that two of the rooms they're in have vaulted ceilings, making some of them very hard to access without removing sheetrock (one of them completely inaccessible from what I can tell and at least 3-4 that would require basically crawling to and from them for every bit of the work). In regards to the one that is inaccessible, is the only "official" solution to rip out the sheetrock and replace the non-IC can with an IC-rated? We had thought of putting all LEDs, but that doesn't alleviate the future issue of putting incandescent bulbs back in later obviously.

    • Reuben Saltzman 4 YEARS AGO

      Hi Craig, That's the only solution I know of. - Reuben

  • louieg 4 YEARS AGO

    You provide a great alternative for the invasion of or escape of energy. keep in mind that LEDs do produce heat. Many use heat sinks to remove the heat.This heat if accumulated can cause damage( premature failure of the electronic circuitry. I suspect that if higher/longer stacks were provided then heat accumulation would be more minimal. I plan to use your solution to air infiltration but enlarge the box.

  • dalton 4 YEARS AGO

    You might want to see if the Styrofoam ice coolers are flammable first ...before placing them over your hot light boxes. Great idea if their flame resistant.

  • eddie gonzales 4 YEARS AGO

    no need to build a styro-foam box, just go to walmart and buy an inexpensive styro-foam ice cooler,,,just the right size....done

  • LT Dupre 4 YEARS AGO

    I have an office in Louisiana (no ice damming to worry about here). My law partner won't let me leave three can lights in our foyer because he was told twenty years ago that if there is any insulation touching the top of the can, that it could combust. Our cans are not airtight but our office is less than ten years old. Is there a risk to leaving the lights on overnight (looks great from the road at night)?

    • Reuben Saltzman 4 YEARS AGO

      The risk is probably quite minimal. If there's a concern, install LED bulbs. They create far less heat. If you're going to be leaving them on overnight, you should do that anyways.

  • Kim 4 YEARS AGO

    We are about to 'renovate' our two garages (one original, one an add on) that are both below living space. We plan to use spray foam in the garage ceiling due to the cold floors in the winter and to give us an air tight seal and then cover with fire-rated drywall. The ceilings are very low and the electrician who installed our new panel suggested we use recessed lighting in the garages. Assuming the use of IC rated lights so that the spray foam can go all around them, is this allowed or does it violate breaking the fire/thermal barrier due to the cut out needed for the light?

    • Reuben Saltzman 4 YEARS AGO

      Kim - you would do well to check with the local authority having jurisdiction, but the consensus I've received from other inspectors on this matter is no. This would not violate the fire separation wall.

  • Debbie 4 YEARS AGO

    why not use ICAT recessed lights? or promote products like air tight inserts that internally seal leakage from attic into living space? get brand name of recessed light & model number. go to mfg and search for air tight insert/baffle/trim. much better than building boxes..which works fine with proper clearance...but sealing them to attic floor with great stuff...come on! and if you don't know...don't speculate. fire hazard

    • Reuben Saltzman 4 YEARS AGO

      Debbie - ICAT recessed lights will only stop air leakage; not heat transfer to the attic space.

  • Julio 4 YEARS AGO

    I am replacing the lights on the first and second floor of my house with recessed lights. I'm using IC rated Airtight housings (http://www.homedepot.com/p/t/202707602?catalogId=10053&langId=-1&keyword=h5ricat6pk&storeId=10051&N=5yc1v&R=202707602#more_info) with LED lights. I was thinking about using a radiant barrier (http://greenjeansinsulation.com/2010/06/the-insulator/) around the canisters in order to insulate them. What's your opinion on this?

  • Bob Wilson 4 YEARS AGO

    I have about 55 Juno IC AT can lights in my house in Alaska and what a dope the guy was who built this house not to mention the dope/me who bought it. I have HUGE issues with Ice Damming and Leaking that I just want to walk away from. I tried the so called Air tight seals from Juno--that was a waste of money. Another one is to use CFL bulbs...if the fixture leaks then it leaks--period. I m truly at a loss and really dont have the energy to crawl around in a low attic building toys boxes to place over 55 fixtures. I feel like suing Juno and my local building code people, these lights should never be installed.

  • Timothy Wilson 4 YEARS AGO

    I have a one and a half story home in Saint Paul that the previous owner finsihed the upper level. There are 3 recessed lights and a ceiling fan, in the top that is about 3 feet wide. Nearby are 2 skylights on the slope. I have a pretty steep roof. I have perpetually had dripping coming from the window frame edges in the winter. I removed the trim and found foam. What is my best action? The recessed lights and fan have big hot spots that show on the roof outside. I don't really want to rip out a ton of sheetrock and start over. I am uncertain how much room I have to work. I had th roof reshingled and they pt a ridge vent in and I still have the same problem

    • Reuben Saltzman 4 YEARS AGO

      Hi Timothy, Your first step should be to identify the source of the moisture. Today it's very cold outside and most houses don't have any snow left on the roof, so this is most likely the result of frost in your attic. I don't know how you could possibly identify this without removing drywall.

  • Angie 4 YEARS AGO

    We have recessed lights in our boutique, They go on and off intermitendly, We think it may be the transformer but were not sure, as these bulbs are not cheap can you please advise. Thanks

    • Reuben Saltzman 4 YEARS AGO

      Hi Angie, The lights are probably thermally protected; they're shutting off because they're getting too hot. Try using bulbs that don't get as hot - lower wattage / CFLs / LEDs. - Reuben

  • Reuben Saltzman 4 YEARS AGO

    Hi Jim, If the can lights that you have are not IC rated, the only safe answer I should be giving you is to make boxes for each of the cans to keep the insulation away.

  • Jim Andersen 4 YEARS AGO

    I'm planning to blow additional fiberglass insulation in to my attic. I have several 15+/- can lights. I don't think that they are IC cans. I have been changing out all the lights to CFLs and retrofit air tight LEDs. Do I still need to make a box for each of the cans or since I'm using bulbs that emit very little heat not worry about having insulation cover the cans Thanks

  • Kyle 4 YEARS AGO

    This post may be a little off topic but I have had a difficult time finding info through thorough Internet scavenging and two different residential electric companies. The recessed lights in my kitchen arc periodically and quite loudly...but this seems to only happen at night. I'm guessing this may be because that is when they are most often used but it usually happens well after they have been turned off at the switch. One of the electricians I had out offered to come back in the evening to check it out but of course when he did we heard nothing. Any possible first step procedures to figuring out this problem? Thank you so much for an answer. This type of problem really worries me for possible fire issues. I have also switched every bulb thinking one of the bulbs was bad and causing the issue, no luck there.

    • Reuben Saltzman 4 YEARS AGO

      Kyle - What kind of bulbs do you have? Have you tried replacing them? If yes, and you're still hearing an 'arcing' sound, you probably do have a problem that needs to be looked in to further by an electrician.

  • Daniel 4 YEARS AGO

    Dear Reuben, My bedroom is located above our den in our two story house, where we watch TV often and have recessed lighting. Additionally, there is an attic above my room. We have noticed that my room is consistantly about 5-8 degrees (F) hotter than the rest of the upstairs and the hallway just outside my room, which is not over the den. This happens year round, regarless of whether we have the central heat or AC on, so it is not a ventilation issue. Additionally, it is not a window or facing the sun problems because other rooms on this side of the house do not have the same problem. Is it possible that these lights downstairs are causing the heat difference? If yes, is there anything we can do without ripping up flooring/ceiling? (Will different types of lightbulbs work?) If no, any ideas what the cause of the heat is? Thanks, Daniel

    • Reuben Saltzman 4 YEARS AGO

      Daniel - it's certainly possible. Try installing LED bulbs.

  • Lee 4 YEARS AGO

    I've recently replaced about a dozen cans that I was told were airtight when I bought them but have since discovered they are not, and I put LED bulbs in them. I live in South Florida where the most important thing is keeping the house cool, not as concerned about the attic and definitely not worried about ice dams! my question is whether ot would be ok to put a rubber gasket seal around the trim of the LEDs to seal them against the ceiling? or is there another way to do that? thanks

  • Brent R. 4 YEARS AGO

    I noticed the floor in my kids room has one hot spot. I traced that spot down to the kitchen below their room right where I have a recessed light. I've never noticed this in the 8 years we lived here. Should I be concerned? Especially since this is a new development? I haven't changed the size or wattage of the builds recently either. Thanks for your reply

    • Reuben Saltzman 4 YEARS AGO

      Brent - check the wattage of the light bulb and compare it to the wattage allowed by the light. You should be able to find this by removing the light bulb. If the wattage of the bulb doesn't exceed the wattage allowed by the light, you should have nothing to worry about.

  • dalton 4 YEARS AGO

    I have ten non-ic lights that protrude up into the attic would it be any better to use the foil faced insulation board to make the boxes instead of the plain foam board?

    • Reuben Saltzman 4 YEARS AGO

      @dalton - I honestly don't know. Good question. I've always thought the foil was only there to allow the material to be left exposed for flame spread and smoke development purposes, but I'm guessing it would also act as a radiant barrier.

  • Minnesota Native 4 YEARS AGO

    An additional thought. I doubt it but ... could replacing the incandescent bulbs that come with the non-IC recessed lights with LEDs reduce the required clearance? (LEDs produce less heat) Dare I say ... completely eliminate it?

  • Minnesota Native 4 YEARS AGO

    I'm about to install non-IC recessed lights. These homemade/makeshift airtight boxes you speak of -- won't they be a fire hazard if the heat cannot escape? Does the 3" clearance include a required opening above? Thank you, Reuben.

    • Reuben Saltzman 4 YEARS AGO

      MN Native - no, installing airtight boxes won't create a hazard as long as the 3" space is maintained. As for your thought on LEDs - I'm sure this would greatly reduce the potential for a fire, however, would the next person who moves in to this house and changes the light bulb back to a standard incandescent be aware of this? Probably not. Stick with the 3" air space.

  • Wendy 5 YEARS AGO

    We purchased a home in March. we have been told that there is usually a large ice dam in one spot on the roof. Previous owners had tried everything to fix it but nothing worked. We have also replaced a pot light that was in the kitchen. with a regular light. The insulation around the old pot light was burnt! Obviously almost a disaster. The good news for us,,,, after reading the above info we are hoping that the ice dam problem is solved. Guess where the pot light was....RIGHT UNDER THE ICE DAM AREA! I can hardly wait for winter to see if this was what caused the ice dam, Such an easy fix.

  • David W 5 YEARS AGO

    Hi Reuben, Great site and discussion. I have a problem with het loss through recessed cans in one story second home we own near Lutsen, MN. We have electric hot water heat and our bills have been atrocious in the winter months even though we turn the heat down to 50 when we are not there. I had a full blown energy audit done this spring to identify areas of heat that are not obvious. The recessed cans are part of the problem but access from above is very limited so I am looking for options. I think we have IC cans in the ceiling with standard 65 watt spots. I plan to switch to CFLs or LEDs to reduce consumption from usage but the heat loss issues is a separate issue. If I can not put rigid foam boxes over the cans in the attic space, what do you recommend I do from inside each room? Are you aware of any new products for remodeling to replace or retrofit existing recessed cans to reduce heat loss? Thank you.

    • Reuben Saltzman 5 YEARS AGO

      Hi David, Your best bet would be to install airtight trim kits for your lights; it won't take the place of insulation, but stopping air movement will make a big difference. Just figure out what brand of recessed lights you have, and search online for an airtight trim kit.

  • Angela Macedo 5 YEARS AGO

    We purchased an older (1977) manufactured home that was a foreclosed home near a lake in California. It gets cool in the winter (as low as mid 30's at times) and very hot in the summer (100+). We didn't know the background of the "remodeling" done to the home because of the forclosure issue. Thus, we have run into a variety of issues...we have "pulled a loose string" so to speak and have "unraveled" many issues. One being there are more ceilings than one home should have! That being said, one of the rooms has vaulted ceilings and we want to add more light into the room with recessed cans. Because of the ceiling issue, there is sheetrock, insulation and then roof with less than 4" to work with. Are there any can lights with such a low profile that could be installed in a vaulted ceiling? Thank you for your help!

  • malcolm from New Ealand 5 YEARS AGO

    Hi there, many new zealand houses have high celings and recessed lights, i have been told that if you replace the old downlighs with CFL and use 10L pails over the protruding fixtures in the attic and cover with insulation ( we have the pink batts type here) and fix it to the celing, would that be safe ?

    • Reuben Saltzman 5 YEARS AGO

      Malcolm - I don't know what a 10L pail looks like, but knowing that 10 Liters is roughly 2 1/2 gallons, I'd say that would be way too small of an enclosure for the lights, assuming they're not IC rated. On the other hand, if the lights are IC rated (meaning you can put insulation right on top of them), go for it.

  • Reuben Saltzman 5 YEARS AGO

    Yes, building insulated recessed covers would help prevent heat from radiating back in to the house... but I personally don't think it would be worth the effort.

  • Hot in here 5 YEARS AGO

    Using an infrared thermometer i am showing 95+F temps on the recessed lights left off all day the rest of the room is 80F. Would building or buying a recessed cover help with the heat? Not much room in that part of the attic, I have R-30 fiberglass insulation covering the cooper-lighting? air-tight ic rated remodel kits installed in the attic along with airtight baffle and gasket installed.

  • Reuben Saltzman 5 YEARS AGO

    Hi Tracey, You can install LED or CFL bulbs to significantly reduce the amount of heat generated by the lights, and you can install airtight baffles to reduce the amount of air leakage. Scroll up to the comments left by John on 1/26/12 and 2/23/12. - Reuben

  • Tracey Norton 5 YEARS AGO

    We have 26 IC rated can lights. They are installed in a vaulted ceiling with no attic space above the lights. Our energy audit confirmed that each light fixture was like an open window. What can we do to seal those lights so we are not wasting heat/cool. We have extremely high electric bills. Thanks

  • Frank 5 YEARS AGO

    We recently purchased a house and have 42 non-IC high hats upstairs and have considerable heat loss going into attic. About half of these recessed lights are on cathedral ceilings with no access from the attic. I would like to replace all the high hats with LEDs and at the same time hope that this provides a better airseal to attic, particularly on cathedral parts. For non-cathedral parts, I am also in the process of getting insulation (cellulose) blown into attic (on top and around the original fiberglass rolls from about 15 years ago). Do I still need to create boxes and have space around non-IC recessed lights if I will use the LED's. I figured the low temps would mean the risk of fire/heat is gone. If so, sounds like my only issue may be with dust as described by some other posts.

    • Reuben Saltzman 5 YEARS AGO

      Frank - the official answer is yes; you still need to create boxes and have space around the non-ic lights, even if you're using LED bulbs.

    • Reuben Saltzman 5 YEARS AGO

      Frank - the official answer is yes; you still need to create boxes and have space around the non-ic lights, even if you're using LED bulbs.

  • John 5 YEARS AGO

    Re: my Jan 26th post. What a difference the air tight baffle makes. I installed the Commercial Electric baffles I found at Home Depot on Jan 28th and noticed an almost immediate decrease in the dust. It's amazing how much insulation dust can be sucked in through the small openings in these recessed lights. I plan to vacuum the ceilings, walls and furniture in the near future which will give me a final reading on how much this helped, but I can already tell that it made a big difference. I would suggest to anyone planning to install blown in insulation into their attic to make sure the attic is absolutely airtight between attic and living area first.

  • Reuben Saltzman 5 YEARS AGO

    Rodrigo - that heat is going to go somewhere. There more heat that doesn't go in to your attic, the more heat you'll have in your house. I think you'd be better off installing LED bulbs. To answer your question though, no, I don't think you'd have any problems if you made the box big enough. If you have IC rated lights, you could make the box barely large enough to cover the light and it would be big enough.


    I installed recessed lights in the kitchen, I live in Arizona it get pretty hot inside the attic during the summer, If I made the box big enough, do you think I will have any problem?

  • Suzie 5 YEARS AGO

    We have a 2-story house built in 2007 and just today noticed water dripping from only 1 of the 6 recessed lights in my kitchen. It happens to be the light above the sink. There is no attic space above the light, just our upstairs hallway. The dripping only lasted a couple minutes. This also happened (same light) about 6 months ago for just a couple minutes. There is no staining, no indication of water damage, but it's making me nervous to know water is coming from somewhere it shouldn't. It did rain some last night, and it is colder here than it's been in awhile (we live in Texas)...just some facts if it helps. Any advice would be greatly appreciated.

  • John 5 YEARS AGO

    Regarding my Jan 8th post, I contacted the Cooper Lighting Company who makes my HALO brand recessed lights and they advised that I had two options. 1. Change my insulation or 2. install the 30 Air Tite baffle in the current recessed fixture and use GA-AT trim gaskets. I did not find the correct HALO baffle locally but did find one made by Commercial Electric that I plan to try. Check back in a few weeks and I will let you know if this works.

  • Matt 5 YEARS AGO

    I bought a house in Chicago with recessed lights in a vaulted ceiling. We are having a lot of snow melt, even when temps are around 20. I'm wondering what my options are short of ripping down all the drywall and doing some spray foam. I read on another site about Continental Electric's airtight baffle trim. Any luck using that? It seems like they might be an affordable solution at about $8 each.

    • Reuben Saltzman 5 YEARS AGO

      Hi Matt, I've never tried using airtight baffle trim; I'm sure it would help, but also changing out to CFLs or LEDs would be a big help as well. - Reuben

  • scott cunningham 5 YEARS AGO

    I just had remodel (non CI) cans installed in my living room. There is an open attic with insulation on the floor. presently the cans are uncovered with the batt insulation because they will over heat and can be a fire hazard. The boxes you talk of to prevent heat loss, will this be a fire hazard? I love the idea and am ready to do it tomorrow.

    • Reuben Saltzman 5 YEARS AGO

      Scott - as long as you maintain the required clearance, it won't be a fire hazard. I say go for it.

  • John 5 YEARS AGO

    Nobody is mentioning insulation dust. I have 15 recessed lights and 2 bath vent/lights. We have a terrible problem with dust in the house which I believe is from the celulose insulation dust migrating through small openings around these items (I have already sealed the furnace outlets). I'm thinking the positive/negative pressure fluctionation from opening/closing doors is causing the celulose dust to migrate into the house. Has anybody had any experience in this area?

    • Reuben Saltzman 5 YEARS AGO

      John - I've never heard of insulation dust coming through recessed lights. I'm sure it's possible, but I've never dealt with that aspect of it.

  • Drew 5 YEARS AGO

    You wouldn't think it'd be an issue, but when I stick my hand up there I feel tons of air infiltration. I did a blower door test and the energy auditor told me ttruth and better seal up my place (house was built in '94).

  • Drew 5 YEARS AGO

    Hi Gred, What about the recessed lights on the ceiling of the first floor of my 2 story house? I want to air seal them, but I cant get access above them to build any kind of box/enclosure like you recommend for attics. I'm in the middle of replacing the 65-watt incandescents to 12-watt equivalent LEDs. I saw a similar post above, but are there *any* options to airseal these canisters? What about silicone caulking the holes in the canisters (and the threshold between canister and drywall)? Since the LEDs run so cool, I would think that this approach would remove the risk of fire typically associated with sealing the canister holes. Thanks! -Drew

    • Reuben Saltzman 5 YEARS AGO

      Drew - I don't know of any way to air seal those lights. I wouldn't go squirting caulk inside the canisters. If they're on the first floor of a two story house, what is the concern?

  • Greg 5 YEARS AGO

    Hi Reuben, Great info here. I was trying to figure out a way to enclose my lights; I have 30+ of them, not my choice. I almost went out and purchased the pre-made enclosures, so you saved me quite a bit of money here. I do have a question for you. There is a vapor barrier below the blown in insulation. Will the foam effectively seal to the barrier or should I peel it back and seal directly to the drywall. I am guessing it will adhere, and I should leave it in place, but I just want to be certain. Thanks. Greg

    • Reuben Saltzman 5 YEARS AGO

      Hi Greg, Foam-in-a-can won't make a perfect vapor barrier seal, but as long as air isn't passing through, it won't make much of a difference. It will certainly be good enough. Foam away.

  • Nancy 5 YEARS AGO

    We would like to update the track lighting in our great-room and it seems recessed lights are the only options. We do not have an attic in that area, would these lights cause problems? Thank you for your time. Nancy

    • Reuben Saltzman 5 YEARS AGO

      Hi Nancy, I assume you have a vaulted ceiling? If so, yes, recessed lights could certainly cause snow melting problems.


    Fabulous timing finding your post tonight! Electrician is wiring my new house this week and I'm putting in about 10 IC-rated AirSeal recessed cans that will fitted with MR16 Low Voltage halogen bulbs until the LED industry ... or another technology we don't know about ... catches up. I decided to go with the recessed, which I've used before and love, only after I was assured that I could foam right up to the housings to ensure that my lighting choice didn't send out the window the money I'm spending trying to get a tight house. But today, my electrician said that we needed to box them in -- not for the reasons you said, but b/c otherwise, the junction box will be unreachable. My attic will be, for all intents and purposes, inaccessible once we sheetrock over. My builder isn't pleased with having to construct boxes, but your photo suggests I could do it in a way that's even better than plywood. Long winded road to three questions: 1. If my electrician is wrong (I'm looking into that), doesn't IC rated really mean that one can eliminate the problem of leakage by ensuring that the cans are buried, in direct contact, with insulation (in my case, foamed at the base and covered deeply in cellulose). 2. If the cans are 1C rated, why would you need the 3" of space on all sides inside the box? 3. If I'm going to try to construct boxes out of rigid foam insulation, did the spray canned foam sealer actually act like glue to keep it all together? To the extent you have answers, thanks very much.

    • Reuben Saltzman 5 YEARS AGO

      CMC - 1. IC rated means you can have insulation up against the light; not that the light will be airtight. Deeply covered in cellulose won't be the same thing as airtight. The name "AirSeal" kind of implies that they'll be airtight though... 2. If the cans are IC rated, you don't need the 3" space. 3. Yes, the spray foam is what I used to seal the box together. I actually used some long drywall screws to hold the sides in place while the foam set, then pulled the screws out later. Good luck!

  • Tejas 5 YEARS AGO

    Hi I have existing lighting in the center on my. Bedroom and want to remove that and add recessed lighting. Do I need to get permits for that? Also I would he getting the airtight ic cans along with the fluorescent dimmable bulbs.is there anything I should look for before starting the work?

    • Reuben Saltzman 5 YEARS AGO

      Tejas - I don't know where you're writing from, so I can't answer your question about whether permits are required. Here in Minnesota, basically any electrical work requires a permit. Yes, there are lot of things to look for before starting the work, but the answer to that question probably goes beyond my ability to teach; there are so many potential red flags to look out for when installing a new recessed light that you would probably do well to buy a book on electrical wiring before starting this process (ie - are the conductors you're attaching to rated for 90 degrees Celsius?).

  • Paul 5 YEARS AGO

    Hello, Great comments and I learned a bunch just reading this. I have ic rated cans and i do run 11 watt L.E.D. lights in them. I was wondering if I should buyild a box around the can light or just use more insulation. What would you recomend as the best option for me too... One other question, I did cut the opening and ripped away some of the plastic that was between the insulation and the sheetrock. Should i replace this and retape this moisture barrier, my old house never had this plastic. It I build the box large enought 6 inch clearence and the ripped out plastic is in the "boxed" area would i need to do anything more? thank you again and great info, very very helpful! Paul

    • Reuben Saltzman 5 YEARS AGO

      Hi Paul, If you're using LED bulbs, it's probably far less critical to build the insulated boxes; just beefing up the insulation over the light would probably be good enough. Try shining a very bright work light up at your recessed light from inside the house, and then go in to the attic and look for any light leaking through. If you can see light coming through around the sides of the light, you probably also have air leaking through as well. If that's the case, it would be worth re-sealing the plastic. If you see light leaking through the recessed light, it's not an airtight light, and you would benefit from building the boxes. You would want to seal the box down to the plastic in the attic to make it airtight. - Reuben

  • ralph ford 5 YEARS AGO

    Hi Ruben, Thanks for the quick reply. I never considered any of these things.What you are saying makes perfect sense. I think it would be prudent to make insulated boxes. That seems to be the best option. Thank you for you time. - Ralph

  • ralph ford 5 YEARS AGO

    I have IC cans in place, ready to sheetrock ceiling. All cans will get LED bulbs. What would be wrong with open cell spray foam sprayed directly on the cans to close all the little holes in the can and seal it where it contacts sheetrock?

    • Reuben Saltzman 5 YEARS AGO

      Hi Ralph, My concern with applying foam directly to the fixture is that the foam might get in through the holes to a portion of the light where it shouldn't be, and possibly cause problems with the light. What if the next owner didn't know about this and then installed standard incandescent bulbs, and caused the lights to overheat and start a fire? Also, you'd be making these lights very permanent by doing this. Those are the only concerns that I can think of. - Reuben

  • Greg 5 YEARS AGO

    Thanks for the super-fast reply. Yes, it says 3" so I'll made some decent sized boxes and pile on the insulation above that. I also plan on going to the new LED lamps from Philips when the price drops a bit more. I believe the draw is just 11W, which should make pot lights just a little less evil.

  • Greg 5 YEARS AGO

    I was about to build boxes of out messy drywall, but I like the insulation idea instead - plus the bonus of added R value. However, is there a fire hazard with the rigid insulation and spray foam? I have non IC pots with halogens.

    • Reuben Saltzman 5 YEARS AGO

      Greg - as long as you maintain the required distance to the insulation, you shouldn't have any problems. Most (maybe all?) non-IC recessed lights require a 3" space. If you remove the bulb and look up inside the light, it should say what the required distance is. You'll just have to make some really big boxes.


    I have a three year old triple-wide mobile with recessed lights in the kitchen. When the home was installed I had the lights get hot, dim, come back on. Manufacturers said there was too much insulation around the lights. (there is no attic). Here we are 3 years later and it is doing it again. Since, I do not have an attic, what lighting is best to avoid this problem. Recessed lights are "hot" for the kitchen.

    • Reuben Saltzman 6 YEARS AGO

      Hmmm... it certainly sounds like the lights are overheating. The first thing I would try is replacing the bulbs with CFLs or better yet, LEDs. LEDs cost a ton of money, but this would still be less expensive than replacing the lights, the bulbs should basically last forever, and they generate very little heat.

  • Reuben Saltzman 6 YEARS AGO

    I just inspected one recently, and it was doing quite well; no melted snow.

  • Chad 6 YEARS AGO

    Have you inspected any homes with unvented attics that use foam insulation (either closed or open cell) at the roof deck (above or below the sheathing.) Just curious how these are doing in this weather condition?

  • Reuben Saltzman 6 YEARS AGO

    Hi Jeff, I guess it all depends on how much you already have. If your insulation is 14" deep, it should be about two feet deep over the recessed lights. In my particular case, I built that insulated box for my recessed light just so I wouldn't have to pile on quite so much insulation. You might want to build a bunch of boxes light that...

  • Jeff Garvey 6 YEARS AGO

    Ok - question on this. My house has 8 recessed lights that go into the attic and guess what....ice dams. How do you suggest insulating them more, should I just add more blown in insulation over the lights or to the whole attic space? I am pretty sure that this is what is causing my ice dam problem and want to fix it but I want it to be a good fix and not just a hokey one. How much insulation do you suggest to have put in up there?

  • Reuben Saltzman 6 YEARS AGO

    I don't blame you a bit. Especially if you haven't purchased a 6 1/2" hole saw.

  • Reuben C. (not the Inspector) 6 YEARS AGO

    I don't think I will ever install recessed lighting in an attic space again for exactly the reasons you've mentioned here. The problems and additional work it creates just doesn't seem worth the benefit. I guess I've never been too much of a fan of recessed lighting in general.