Properly installed can light vs. surface mount
I am doing more research in lighting after an earlier question and reading other articles. The general consensus I am seeing is: Can lights are evil. The logic? Because of air leakage.
So, if we step back and compare that to what appears to be the golden solution; flush/surface mount lights installed in a j-box, we seem to solve that problem. But this assumes the installation is done properly. So you have to seal around the exterior of the jbox and you also have to seal any romex penetration at the top of the box. Spray foam? No, some people argue that is a fire hazard with an LED transformer inside the box, or argue that it’s not permanent and will harden and break off. Caulking? Sure, as long as it doesn’t shrink in extreme temperatures.
I think in reality, the key point is sealing between the ceiling drywall and the light trim piece. If this seals, then there is no air leaking even if there is a baseball size hole in the light’s fixture, right?
I’m comparing the two, and although flush mount are typically easier to install, they also cost 3x the price for the lumen range I am looking at, and they seem to produce a glare. If I were to diligently seal a recessed IC/AT fixture, would I be shooting myself in the foot by NOT using the newer slim-mount lights? I will have a traditional vented attic with plenty of cellulose above the fixtures, so the low clearance of a j box is not much of a concern for me like others. I will be using these in the kitchen, bathroom, and office probably while I want to use a different style to light the ceiling as GBA seems to preach is a better method versus can lighting. I agree, but also feel each room has a certain kind of light. (I can’t benefit from lighting the ceiling in my kitchen when I want to see the countertop. Plus I can’t install a sconce where cabinets are taking up wall space.)
Any input on this topic, what else is missing from the puzzle? If clearance is not a problem, and installation is done properly to make sure there are no air leaks, what is there to lose when compared to jbox + surface mount at two or three times the price?
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Can lights intruding into insulation layers makes for a thin spot in the insulation that also corresponds to a local heat source (the light). With surface mount the thinning is limited to a couple of inches.
Down lighting in general isn't a great for ambient light, since it's inherently glare-prone and lower efficacy at any light level than zero glare lighting, and it casts shadows.
Counter top lighting is best done by under-cabinet fixtures, not the ceiling. It's best placed near the front edge of the cabinet (furthest into the room), directed toward the wall. The back scattered light off the wall fills in shadows and reduces glare.
Cabinet top lighting using the ceiling and remaining wall height as wall-wash & diffuser is also glare free, and can cut the glare from any down lighting in that area by brightening up the field of ceiling surrounding the glaring bright spot.
If you have R-40 or R-50 is it still a concern to have something sticking up 6 to 8 inches though? I know in low clearance spots it's a huge deal. I guess I didn't think the lights would make that big of difference in the attic R-value and that something like a window would be a much larger R value leak than less of an already high amount of insulation in spots of the attic?
I agree under cabinet is best, but it does nothing to help see cabinets above the countertop. Plus, when lighting the room, it's nice to just have general light in the area. The main argument is that ceiling light casts shadows on the person, but under-cabinet light would cast no light on the person which is undesirable. Overall I see cabinet lighting as a secondary and not a primary for my living style. But that's getting past my discussion point, too.
Hi Nicholas,
I have just installed several Lotus LED lights (1" thick) and have been totally impressed with the illumination provided. I am using them in hallways and the laundry area and I needed a surface mount because it is a t&g pine ceiling/second floor. They have a good beam angle (110 degrees), CRI is 84 and glare is minimal. They are not cheap but for me they were worth the extra money.
Nicholas,
My expression for readers like you is "advice resistant." That's OK. It's your house. Build it however you want.
The standard advice given here -- avoid recessed cans -- is based on the experience of home performance contractors who have performed dozens (or, in some cases, hundreds) of blower door tests and infrared camera scans. These recessed cans are thermal disasters. They show up like bad skin disease on an infrared camera -- red eruptions.
You can try to seal the leaks if you want, but you will miss a few. You can mound up the insulation if you want, and that's better than not trying, but the insulation is air-permeable. Once you turn on the light, it turns into a little chimney, a kind of engine for the stack effect.
But, as I said -- it's your house.
I suppose one could build a foam box around each can light. Seems like a PITA however.
John,
Airtight boxes above recessed can lights can help -- but be careful. Such a cap can be dangerous (can be a fire hazard) if it is installed above an older fixture that is not IC-rated.
For more information, see Recessed Can Lights.
Up-lighting (cabinet-top or cove lighting) provides a MUCH better quality of lighting "...to help see cabinets above the countertop...", since the back-scatter from the ceiling & walls is essentially shadow free, and high efficacy, particularly in comparison to an array of discrete down-lighting spots (either recessed or surface mount.)
Valence lighting and sconces can work well too, but the available wall area for those are usually limited in kitchens.
Nobody is suggesting that under cabinet task lighting was a good way to set the ambient light level. (Or at least I would never make that suggestion.) But it's far more functional task lighting than cheaping out with an array of ceiling mounted down lights set above the edge of the counters.
Before locking in to a lighting solution it's worth taking a look at the home lighting primer on Lighting Research Center website , courtesy of the Rensselaer Polytechnic Institute. For each type of room the start with a base case, and offer up multiple alternatives/adjustments. It seems a bit retro-fit oriented with a "fix this" point of view, but the illustrations are useful for figuring out what would work in new construction as well.
http://www.lrc.rpi.edu/patternbook/rooms/index.asp
Dimmable linear fluorescents (or their linear LED equivalents) in valances or coves offer the most flexible, efficient & highest efficacy way of setting ambient lighting levels in most rooms. That "sea of down-lights" popularized in 1950s (seen in many of the "base case" examples) looks downright mousy by comparison.
Nicholas,
Here is a link to a GBA article that covers many of the lighting principles that Dana is espousing: Martin’s 10 Rules of Lighting.
We have no upper cabinets, so no under cabinet lighting. We have recessed cans in the kitchen. One set of four over the counter. Two sets of four and two over the island. One individual can over a small counter next to the fridge. We also have a set of five globes over the island that we use for atmosphere when eating at the island. Above the ceiling is conditioned space.
When preparing meals, we usually have on the two sets of four (over the counter that has sink and cooktop and over island closest to counter). The result is a well illuminated work space. We designed the lights after experiencing our old kitchen, which functioned well, but needed more lighting. A major consideration was our inability to find fixtures that fit with our spare, minimalist design preferences. If we had it to do over, we'd keep the cans. A big bonus is the low cost. Another is that they are unobtrusive. With leds in every fixture, they are inexpensive to operate.
I offer this as just another viewpoint. I agree that cans are generally not appropriate in ceilings below unconditioned space.
Bowl shaped pendant lighting over kitchen islands usually works out pretty well, and better than down lighting alone. By lighting up the ceiling above the island shadow and glare are minimized.
The definition of glare is the contrast in intensity between a localized light source and the visual field surrounding it. By making the ceiling brighter, the contrast with the down light isn't as severe, and human eyes will adjust to the average. This yields higher visual acuity even at lower ambient light levels as measured with an instrument.
Nicholas,
The discussion seems to have started from a strange assertion in your first post - that flush mount LEDs are problematic because they need to be installed well.
Surely all air selling needs to be done diligently? Use fire proof foam and high temperature caulking if excessive heat is the worry. Whatever their shortcomings they pale in comparison to those of can lights.
Stephen, that sounds like my situation but with wall cabinets.
Dana & Malcolm, I'm open to flush mount LED. Don't get me wrong there. I want the best product for my dollar. There are a few name brands of flush mount lights but they are about $60 each. If I can trial these lights on the ceiling, I will. I want to see how obtrusive the light is compared to some trusted recessed cans that I currently do have.
I believe my original idea in posting this question is to discuss what is truly wrong with an IC/AT Rated Recessed LED Lights? Assume I heed caution on diligently installing the fixture which has few penetrations in the can in the first place that I would calk around, and then, I would also make sure the LED Trim that snaps in has a gasket that seals. Yes, old recessed lights are awful. They are also 20+ years old. If the reason for putting recessed down is because they truly are not sealable and truly are inferior to a flush mount that does stick down, and that does possibly create a glare when placed say next to a window or next to anything shiny, then I would probably be more convinced.
Do you folks have any recommendations on some time-tested options for flush mount LED lights that are in the 3000k to 4000k range and priced $30 to $55? I have only seen the Phillips brand recommended here and I'd like to see other options that are proven to not die from premature failure after their Jbox is completely air tight.
I really like the cheap flush mount LED disks available at Home Depot under the Commercial Electric brand. In the in-store display they look cheap, but installed they look unremarkable, and most importantly, the light quality is my favorite warm white I've seen from any LED. I've tested and lived with several different >90 CRI LED sources, and these are definitely my favorite for light color.
http://www.homedepot.com/p/Commercial-Electric-6-in-Soft-White-Recessed-LED-Can-Disk-Light-CE-JB6-650L-27K-E26-2/206105625
But they are 2700K, whereas you said 3000 to 4000. I've also used the Sylvania Ultra LED Disc, which comes in 3000K or 5000 K, and is rated 90 CRI. The ones I have have been in for more than a year and work fine and the looks and light quality are both very good.
https://www.menards.com/main/lighting-ceiling-fans/indoor-lighting/recessed-lighting/recessed-lights/sylvania-led-4-5-and-6-13-watt-soft-white-recess-and-surface-mount-disk/p-1444431945418.htm
Charlie I did find those today (the Commercial Electric). What about these guys? I had kept skipping them thinking they were standard recessed lights but they actually say JBox mount. I have never heard of the brand, but I don't know very many. http://www.homedepot.com/p/EnviroLite-Easy-Up-6-in-Warm-White-LED-Recessed-Light-with-93-CRI-3000K-J-Box-No-Can-Needed-EV608941WH30/205978332
Edit: Nevermind. They are not screwed to a sealed box but instead an all in one item. Would probably require caulking to seal it properly like a recessed fixture would.
I have used Sylvania before for regular bulbs, and those are super cheap at Menards.... I don't know what could possibly be wrong with them besides that they are more obtrusive than the other options.
It's looking more probable if I can find something reputable, high lumen, around 3000k, and decent CRI. Asking for too much? :)
Also gonna have to look for a good set of sconces for some rooms. Probably LED sconces unless I find standard socket ones that take LED bulbs.
I had a few unsend can lights. I put them in the basement between the floor joists where they couldn't do any harm. They are the most antiquated junk on the planet. Use the LED and develop an uplight solution if you can using some led tape lighting that runs around the room on something like a nice crown molding that acts like a freis molding. Be creative. But don't put that junk into your attic ceiling.
Use a standard J box and air seal it nicely. http://www.thebrightspot.com/p-9344-kichler-43848led30-very-low-profile-3000k-flush-mount.aspx
There is a sale that makes these $30 or so. They have other color warmths as well. How do you buy a can light, trim and bulb for that money and spend the time jerking around sealing it to be worthwhile when you can install J box, caulk it well and put this up. If you are a fanatic, you can put osb on ceiling, tape seams, and use resilient channel for your rock, keep all wires and shallow Jboxes underneath the attic in a chase, and load up your cellulose on top of that osb with no real penetrations into the attic at all. Just don't use cans in second floor or in attic floor.
These all look like they have specialized LED lamps. What are the chances replacement lamps will be available if the LED burns out early, or has to be replaced due to short or damage in 5, 10 or 12 years?
I understand the caveat to not use can lights, but in regards to surface mount ceiling lights attached to a J-box, why would an LED specific light be any better than a regular fixture with an LED bulb?
C.L.,
Any type of surface-mounted fixture is preferable to a recessed can light. You're right: such a surface-mounted fixture doesn't need a hard-wired LED lamp. If the fixture accepts screw-in Edison-style bulbs, you can install a 99-cent LED lamp from your local hardware store in this type of fixture.
If you go this route, remember to use caulk to seal the holes in the back of the electrical box where the cables enter the box, and remember to use caulk to seal the crack between the electrical box and the drywall.
Martin - Thanks for the response to this older post.
If I understand correctly, we are in agreement that the LED "Can Lights" that mount to a j-box are really not too different than any surface mount light into which you screw an Edison based LED bulb.
For both of these uses, doesn't the advice to seal the holes where the cables enter the box, and seal between the box and the gyp would apply equally?
And if you use the specialty j-box that seal where the cable enters, you still need to seal between the box and the gyp, right?
So is a proper summary of the advice to use any fixture that can be installed to a well sealed J-box, and make sure that fixture has an LED bulb?
Has anyone tried these on Amazon that are just over $7/each: (it won't let me post a link, but search Amazon for (12-Pack)- 5/6” Dimmable LED Disk Light Flush Mount Ceiling Fixture, 15W (120W Replacement), 3000K (Soft White), ENERGY STAR, Installs into Junction Box Or Recessed Can, 1200Lm)
Has anyone found any jbox "can lights" that mimic the look of real recessed cans instead of surface mount?
Has anyone found any jbox "can lights" with the gimbel function to serve as spot lights for art?
C L,
In response to: Has anyone tried these on Amazon that are just over $7/each: (it won't let me post a link, but search Amazon for (12-Pack)- 5/6” Dimmable LED Disk Light Flush Mount Ceiling Fixture, 15W (120W Replacement), 3000K (Soft White), ENERGY STAR, Installs into Junction Box Or Recessed Can, 1200Lm)
I suggest if you have the time, you purchase a few and install them to see how they look. We are building a house and I have tried a Cloudy Bay 7" 12W fixture which was OK. We also tried a Halo 9W 6" round which we really like and are planning to use for our house. We'll be installing about 25 of these. These are $25 at the Homer and I think that is a great price. I'm planning to buy a few extra in case of failures but at 50,000 hours life I think they will outlive me.