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  1. Kenny78 | | #1

    The j-boxes are going to be much cheaper than cans. The boxes should be easier to air seal and present an easier insulation detail.

  2. iLikeDirt | | #2

    I've used those surface mount LEDs in junction boxes. They're great. Get a kind of box with few penetrations and then air sealing them is a cinch. Be careful with the LED modules since they have transformers in the back that stick out and not all of them will fit in all boxes, depending on the internal configuration of the boxes. Buy one as a test before pulling the trigger on an order of 100 unless you're positive it will fit.

  3. Expert Member

    Using boxes also allows you a lot more flexibility if you decide to change the fixtures the future.

  4. Deleted | | #4


  5. GBA Editor
    Martin Holladay | | #5

    Like everyone else, I urge you to go with the pancake-style LEDs instead of the recessed can fixtures.

    Two questions, though:

    1. One hundred fixtures? Really? Are you using these in every room in the (very big) house? Because if you are, you might consider using a more subtle, sophisticated, nuanced lighting design.

    2. Downlights aren't appropriate for all rooms. In many (even most) cases, you will get a more pleasing effect if you bounce light upwards, off a white drywall ceiling, rather than aiming so many downlights at your floor.

  6. dankolbert | | #6

    Yeah, I was hoping that was a typo.

  7. charlie_sullivan | | #7

    I'm a fan of the new J-box surface mount LED modules, particularly on an upper level where the ceiling plane is the air barrier.

    You may want to buy a few samples and see if you are happy with the color, perhaps starting with some $4-10 screw-in LED replacements just so you can try a few colors at low cost. Tastes vary, but LEDs are available in a variety of colors. 2700K is a very warm yellowish incandescent light. 3000K is whiter, and you can go up to 4000K or 5000K if you like a cooler bluer color. Most Americans seem to like 2700K or 3000K, perhaps because of bad memories of terrible old fashioned pre-CFL "cool white" fluorescent lights in offices and schools.

    If you are picky about color, you might also look at CRI (color rendering index), which is 80 for typical LEDs and 90+ for ones that go all out to achieve better color. 100 is ideal.

    When we did our lower-level studio space a year or so ago, I couldn't find any low profile surface mount high CRI modules, so we put in recessed cans with Cree "TW" series LED modules. At about $10 for a can and $20 for the module, that is actually cheaper than some surface-mount modules, although it's probably a little more work to install. And the light quality is terrific.

    I see that there is now a high CRI surface mount module available from Green Creative:

    We put a Sylvania surface mount LED module on a J-box in a hallway. Our impression is that the lowest lumen output version of that product has more light than we need or want for the hallway. Unfortunately, there isn't as much variety in output levels available as there is with simple bulbs (and it's not as easy to swap out bulbs), so we may end up putting in a dimmer just to throttle back the light semi-permanently.

  8. Deleted | | #8


  9. pbyar | | #9

    There are four factors which affect customer satisfaction with led lights: color temperature, color rendering index (cri), lumens and dimmer performance. The Nuovo unit has an incandescent-like 2700K color temp, maybe acceptable cri of 80+ and high lumens (810). The Eaton/Cooper Halo unit has a slightly whiter color temperature (3000K), very good cri of 90 and maybe acceptable lumens (675). Eaton/Cooper offers dimmers, so you would *think* that they would avoid buzzing and not-dim-enough dimming.

    Whether surface mount or retrofit, led technology is developing so rapidly that the only way to be confident of success is to see the system at work.

  10. Deleted | | #10


  11. Expert Member
    Dana Dorsett | | #11

    "I am open to lighting ideas, any feedback is welcome."

    An all down-light lighting scheme usually ends up with much lower visual efficacy than balancing it with up-lighting, due to the glare-factor. The definition of glare is when there is a large intensity difference between a light source and it's surrounding field is high. That causes human pupils to constrict, which then needs higher ambient light levels for achieving the same visual acuity- humans can see more at lower ambient light levels when the glare factor is eliminated. When there is sufficient up-lighting to brighten the ceiling around the down-lights, or setting the ambient light levels entirely with up-lighting, the effectiveness of using downlighting for accent or local task lighting goes up.

    If you haven't found it already, there is a large amount of lighting-design resources available online at the Rensselaer Polytechnic Institute websites, including discussions on how to effectively integrate daylighting etc.

  12. markgimmeshelter | | #12

    We've had good response on the new generation of LED fixtures which are moving away from the Edison base style bulb which is not well suited to the directional nature of LEDs. One complaint that I do not see a whole lot of conversation about is radio interference from LEDs. I guess traditional radio is no longer a primary media for many households in this world of podcast and streaming services.

  13. propeller | | #13

    For a new construction try not to share neutral wires amongst lighting circuits. LED on dimmer can start flickering due to electrical noise carried via the neutral wires. Don't ask me how I found out...

  14. user-6433648 | | #14

    We recently finished furring down the rafters of the cathedral ceilings in the home we purchased in order to add more adequate insulation. I am looking at possibly using some of these junction box mountable LED lights in that living room as well as in our new kitchen. Could anyone provide an updated recommendation for a particular manufacturer and model that you have been pleased with? Thanks.

  15. richmass62 | | #15

    Looking at what's out there on the market, it appears I can get an IC rated 4" Can with a junction box for around $9. Then I can add a 7 watt LED retrofit to it, again for $9. The lamp manufacturer is B2ocled.

    The alternative is just to install a ceiling junction box and then flush mount an LED onto it. The difference is that the flush mounted LEDs use a lot more watts per lumen. So is there a newer flush mounted ceiling LED available, that is as "green" as the can-mounted solution?

  16. user-2310254 | | #16


    One concern with conventional cans is that they are creating pathways for conditioned air to leak into unconditioned space. Where is the insulation located in your attic space?

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