I am thinking of installing LED strip lights into my shed. I have found that there is something called aluminium profile that can be installed where the LED strip goes on top of it or inside it.

Is the purpose of aluminium profile only to diffuse the LED light using a translucent surface or are there other purposes as well like changing angle of the LED strip? I am asking this since there are different type of aluminium profiles and I am not at all sure what their aim is.

  • 1
    I changed angle using wood (triangular 1m*1cm*0.5 cm profile) - this was cheaper and less cumbersome. Also, not all profiles include diffusors (or even options for them) - make sure to check twice before buying. If you have enough LEDs per meter or illuminate stuff far enough you might not need them. Commented Feb 6, 2023 at 12:33
  • so due to cost reason, a wooden profile at an angle would be preferred?
    – gyuunyuu
    Commented Feb 6, 2023 at 19:56
  • 1
    For ME, I believe it was the best option, yes. Cheap and small. I don't think it would be the best for everyone - say if you also need/want heatsink or diffusors or protection or ... (see answers) this wooden thingy doesn't help you much. Commented Feb 6, 2023 at 20:40
  • 1
    The aluminium profile may function as a heat sink as well. I have tri-colour LEDs that get very hot in use, the strip draws something like 40W per meter. The aluminium profile heat sink is required.
    – dotancohen
    Commented Feb 7, 2023 at 7:27
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    @TimSparkles I believe that's efficiency of the LED alone, which is pretty much bound to be same. But constant voltage LED strips are resistor-regulated, so it's not possible to match the efficiency of switch-mode regulation of integrated light units. Also, you have to subtract the ~80-90% efficiency of the 12V PSU you're using, which is already accounted for in integrated units. On top of that you get the shitty distribution profile of bare led, so not all your lumens go where you want them, yielding less lux. A decoration. (Under cabinet there's shadow so any light is a big improvement).
    – Agent_L
    Commented Feb 8, 2023 at 9:51

3 Answers 3


I believe it mostly serves as a convenient way to mount the strips, and transfer money from you to the people who make and/or sell it.

Some versions do appear to have a diffuser as well as the mounting strip, but that's more than just an aluminum profile, it's one with a diffuser strip. Some serve to alter the angle of the strip light. All serve as a thing that the strip light slides or pops into.

These differences from a plain mounting channel appear to be obvious, to me - if it has a diffuser, then part of its function is to diffuse. (That's not free, by the way - you lose some light going through the diffuser.)

If it mounts the strip at an angle from the surface, then angling it is part of its purpose.

If it does neither, it's just a mount.

  • Confirming with an actual case. We used one for over the kitchen bench, under the cupboards. It makes it look tidy as it's visible and for the same reason the diffuser makes it look more like a strip than discrete LEDs. Commented Feb 6, 2023 at 2:26
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    -1 Why so negative? If someone wants a clean-looking light strip with very easy mounting, then this is the way to go. It's a feature, not an evil money grab. If the aluminium were optional, they would leave it off (or go out of business as everyone would just buy LEDs on a strip).
    – AnoE
    Commented Feb 6, 2023 at 9:27
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    LED strip glued to ceiling directly will usually fall off pretty quickly, unless you do a really good job with cleaning the surface. So yeah, a lot more convenient to glue the strip inside a profile and screw the profile in place.
    – jpa
    Commented Feb 6, 2023 at 12:04
  • 1
    @FreeMan Heh, yeah, if the profile is one where the only mounting holes are under the strip. But those are annoying to reposition, so I would avoid them.
    – jpa
    Commented Feb 6, 2023 at 14:25
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    High power leds have a warning "do not run without a heatsink". So that's a very important purpose aluminium serves. People tend to think that "leds are cool so heat is not a problem", while leds actually create heat problems and require complicated cooling.
    – Agent_L
    Commented Feb 7, 2023 at 9:36
  • They provide physical support, e.g. when mounting a strip across several rafters.
  • They provide some physical protection, e.g. against swinging garden implements.
  • Some provide protection against moisture, but they must be carefully sealed at wire entries and the like.
  • They provide a heat sink. High power strips, e.g. with four rows of LEDs, may require a heat sink.
  • What is "swinging garden implements"?
    – gyuunyuu
    Commented Feb 6, 2023 at 19:55
  • @Quantum0xE7 Not sure what your shed is for, but if it is used for scythes (The classic swinging garden implement!), rakes, pole pruners and other outdoor tools then there is a fair chance that one of them will hit a light while being casually handled. If it's a workshop then lumber may be the predominant hazard. Potting wheels shouldn't be much of a problem, nor large televisions.
    – HABO
    Commented Feb 6, 2023 at 21:07
  • 3
    Re: Physical support - an aluminum channel is the difference between a clean straight line and a slightly wobbly line. Diffusers on top of the aluminum channel are the difference between a clean, solid line and a dotted line.
    – Amanduh
    Commented Feb 6, 2023 at 22:27
  • @Quantum0xE7 Garden implements that swing.
    – Agent_L
    Commented Feb 7, 2023 at 9:31

Listen to HABO's answer and the one from Ecnerwal, but there are some things to add. I don't have enough reputation to leave a comment, so my advice comes as an answer:

  1. Adhesion: Most LED stripes have poor glue strips and will curl up and away from the surface they are glued on. This is especially true for grainy surfaces like wood. Aluminium profiles can be screwed and offer good contact, some even allow you to slide stripes in from the side, mitigating the whole problem. This will also help exchange the stripe when a few modules start to fail
  2. Diffusion: You probably think that open strips will be fine, but that is rarely the case. Diffusors make a world of difference because they turn blindingly bright dots into soft bars of light (when viewed directly). Making one yourself is possible, but takes a lot more work than using premade diffusion strips. An alternative is to use indirect light by shining on an adjacent surface.
  3. Straight lines are hard to to when gluing by hand, profiles help
  4. Expect the stripe to get warm, heatsinking LEDs will prolong their life. This can be fine when running a low brightness, but that's rarely the case for working lights in sheds.
  • Just a note regarding diffusion - do not assume you need diffusor just because the led strip itself has many bright spots. At few meters light may be completely uniform so diffusor would only throw some light away for no gain. But if your LED strip is illuminating something close or you actually look at it often, you indeed want something uniform. Commented Feb 7, 2023 at 10:00

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