Aluminum Channels for LED Strip Lights - Are They Worth It? An In Depth Look
What Are Aluminum Channels for LED Strip Lights?
Despite the versatility and ease of use that LED strips offer, strictly speaking, they are more of a lighting component rather than a finished lighting product. Aluminum channels, or sometimes called aluminum extrusions, serve a variety of functions that help LED strip lights look and work more like a traditional lighting fixture.
The aluminum channel itself is relatively simple and straightforward. It is made of extruded aluminum (hence the alternate name), which allows it to be made long and narrow, which is perfect for a linear lighting installation where LED strip lights are considered. The channels are typically "U" shaped, with an approximately half-inch wide slot along which the LED strip light can be mounted. The most common length is 3.2 ft (1.0 meter), and they are often sold in packs of 5 channels as this matches the typical 16.4 ft (5.0 meter) LED strip reel length.
In addition to the aluminum channel, a polycarbonate (plastic) diffuser is oftentimes included. The polycarbonate diffuser is also manufactured via an extrusion process, and is designed to easily snap on and off of the top of the aluminum channel. Once in place, the diffuser typically sits approximately a quarter to half an inch away from the LED strip lights, which are mounted at the base of the aluminum channel. As its name suggests, the diffuser helps to provide diffuse light and improve the light distribution of the LED strip light.
Do Aluminum Channels Help with Thermal Management?
In the early days of LED lighting, heat management was one of the biggest hurdles in light bulb and fixture design. Specifically, unlike incandescent or fluorescent lamps, LED diodes are very sensitive to high temperatures, and improper thermal management can lead to premature, or sometimes catastrophic failure. In fact, you may recall some early household LED lamps which had elaborate aluminum fins, which help to increase the total surface area available to dissipate heat into the ambient environment.
Among commonly manufactured and used materials, aluminum is one of the best materials for heat management, as it features thermal conductivity values second only to copper (which is far more expensive on a per-ounce basis), and as such, aluminum channels absolutely do help with thermal management, as the direct contact allows for the heat to travel from the LED strip to the aluminum channel body, where a larger surface area is available for heat transfer into the ambient environment.
In recent years, however, the need for thermal management has been reduced somewhat, much of it being driven by the reduction in manufacturing costs. Because the cost per diode has come down, lighting engineers and designers have been able to use a higher quantity of diodes in lamps and fixtures, each driven at a lower drive current. This leads not only to improved diode efficiency, but reduced thermal buildup due to the diodes being more spread out than before.
Similarly, because Waveform Lighting's LED strip lights use a high quantity of diodes per foot (37 per foot), with each LED driven far below its rated current, the LED strip can be operated safely without the need for any thermal management at all. While they do warm up a bit during operation, they are specifically calibrated to remain well below maximum temperature ratings even with the LED strips suspended in still air.
So, do LED strip lights need aluminum channels for heatsinking? The short answer is no, as long as the LED strip is manufactured using high quality materials without diodes being over-driven.
Diffusers & Light Distribution
As we discussed above, the aluminum channel is not really necessary for thermal management. It does, however, offer a robust mounting base for both the LED strip as well as the polycarbonate diffuser which offers some very nice benefits in terms of light distribution.
Typically, the diffuser is frosted, which means that light can pass through, but as it passes through the polycarbonate material, it is scattered in many different directions, creating a soft, diffuse effect that is quite different from the raw LED "dots" that would otherwise be visible.
Whether or not the LED strip is covered with a diffuser can have a significant effect on the overall lighting in one of two ways: direct glare, or indirect glare.
Direct glare occurs when someone looks directly at a light source, and due to its extreme brightness, it causes minor discomfort and an instinctive urge to look away. This most often occurs with point-source lights such as spot lights, stage lights and even the sun. Brightness is generally good, but when it shines directly into our eyes from a small surface area, this can cause glare and visual discomfort.
Similarly, an LED strip light that points directly at someones can cause direct glare, as the individual LEDs shine directly into their eyes. While the brightness level of each individual LED on an LED strip is not as powerful as a high power spot light, this can nonetheless cause discomfort. With a diffuser, however, the individual "dots" of each individual LED are obscured, and the result is a far softer and more comfortable light beam that does not cause as much discomfort should someone look directly at the light source.
Direct glare is generally not an issue if the LED strip lights are concealed and cannot be seen directly. For example, LED strip lights installed as under-cabinet lights, toe-kick lights, or inside retail shelving are generally below eye level, and therefore not susceptible to direct glare problems.
Indirect glare, on the other hand, can still be an issue if a diffuser is not used. Specifically, indirect glare can occur when the LED strip lights shine directly onto a material or surface that exhibits high gloss (also known as specular reflection).
Below is a photo showing a section of the aluminum channel with and without the diffuser attached, shining onto our workshop floor, which is made of concrete but with a layer of wax finishing. Although the individual LED emitters are not directly visible from this angle, they are visible as reflections off of this glossy surface, which can be somewhat distracting. Do keep in mind, however, that this photo was taken with the LED strips basically on the floor - a set up that you would not see in practice.
In the photo below, the same LED strip section is directed at a cardboard surface, which we typically associate as being more "matte" (also known as diffuse reflection). In this situation, we actually are hard-pressed to find any significant differences in terms of the reflectivity off of the cardboard surface.
Finally, we take a look at a side-by-side comparison photo of some (admittedly uninspiring) objects in our office, with the LED strip lights positioned approximately 12 inches away. You may be a bit surprised to see that the two photos appear quite similar - this is likely due to the fact that even without the diffuser cover, an LED strip light with a high density emitter configuration does emit light from multiple point-sources, which prevents hard shadows from being cast.
We do see a bit of the indirect glare in the form of small dots on the pen and plastic packaging when the diffuser is not attached. The bolts, in their various positions and angles, do not seem to be affected by the diffuser due to their relatively high diffuse reflection properties.
Aesthetics & Other Practical Considerations
So far, we've discussed aspects of the aluminum channels that are quite technical and from the perspective of LED strip light performance and lighting science. The aluminum channels do offer some additional practical benefits that are certainly worth considering.
The first immediate and obvious benefit is the aesthetics aspect of the aluminum channels and the diffuser covers. Although we love our LED strip lights and it pains us to say this, a bare LED strip light with its circuitboard and bright yellow phosphor-coated emitters doesn't always mesh with the other interior and architectural elements of a space. An aluminum channel and diffuser cover can certainly help it blend in, and can provide a much more polished and professional finish.
The second benefit is the ability to protect the LED strip light from dust, debris and unexpected impacts. Although longer-term considerations such as cleaning are likely not top-of-mind when you're excited to install new lighting, the unfortunate reality is that the LED strip lights will inevitably gather dust over time that requires occasional cleaning. The aluminum channels will help prevent dust buildup on the LED strip light itself (dust and moisture are thought to contribute to the potential for short circuits) and allow for easier cleaning of the aluminum channel exteriors and diffuser covers only.
Do keep in mind, however, that the aluminum channels and polycarbonate covers are by no means water tight, so they will not be helpful for any installations that require moisture or water-proofing.
While unlikely, having an additional layer of protection between the LED strip light and any stray objects or equipment can be helpful, should an unexpected impact occur. Because the aluminum channels are far stronger than the LED emitters, they are far less likely to get damaged should a wayward object accidentally strike it.
Finally, although they operate on very low voltage levels (12 volts / 24 volts) and are generally very safe, LED strip lights do nonetheless carry live voltage and current. Especially if the LED strip lights are installed at a height or location that is relatively accessible, especially to young children, this may be an additional benefit and aspect to consider.
Situations Where the Aluminum Channel Are Not Needed
In situations where neither direct nor indirect glare is a concern, and none of the aesthetics or practical issues we discussed above are of issue, we would recommend going right ahead and skipping the aluminum channels and diffusers altogether. Especially with the ease of mounting via the 3M double-sided adhesive, installing LED strip lights directly can be perfectly fine.
Generally, situations most likely to not require aluminum channels are those in which the LED strip lights shine upwards toward the ceiling, rather than directly downwards. This is a relatively common lighting technique used in cove lighting as well as LED strip lights installed on crossbeams and trusses.
In these situations, direct glare is not a concern, because the lights shine away from the occupants of the space, so the emitters are never projecting light directly towards people. Indirect glare is also not a concern, because generally, the light is projected towards a relatively diffuse wall surface that is usually covered in a matte paint finish. Finally, aesthetics are less of a concern, because the LED strips are hidden from direct view as they are typically mounted behind architectural elements and are effectively invisible.
What Are the Disadvantages of Aluminum Channels?
We've discussed the benefits of aluminum channels at length, but we certainly want to make sure that we cover some of the downsides as well.
The first obvious downside is the additional cost. Don't forget that in addition to the material cost, labor cost during installation can also be a factor. Additionally, because the diffuser has a transmissivity value of approximately 90%, this means that you will see an approximately 10% decrease in brightness compared to installing the LED strip lights without a diffuser. To achieve the same level of brightness, this translates to a 10% higher LED strip light and accessories purchase cost (as a one-time expense), as well as a 10% increase in electricity costs over time (as an ongoing expense).
Another disadvantage is that the aluminum channels are rigid and cannot be curved or bent. This can be a significant downside or even a dealbreaker if the flexibility of LED strip lights is an absolute must. Although the aluminum channels can be cut using a hacksaw, this can be somewhat cumbersome and is an additional downside, especially when compared to the ease of cutting LED strip lights to length.
Finally, especially if you are installing LED strip lights with ultra high color accuracy such as our own ABSOLUTE SERIES LED strip lights, you will likely be concerned about the effect of the diffuser cover on the light output.
Our basic tests have shown that applying the diffuser cover does note have a significant effect on the CRI, but it can lower the color temperature by approximately 150-300K for daylight white color temperature LED strip lights (far less for warm white color temperatures due to the way color temperature is calculated). While color shifts of this magnitude are typically not consequential, for a calibrated viewing environment for industrial or manufacturing processes that require adherence to standardized viewing environments such as the ISO standard for D50, the diffuser may introduce an additional layer of uncertainty and may be worth foregoing.
Browse Waveform Lighting Products
A-Series LED Bulbs
Our A19 and A21 lamps fit in standard lamp fixtures and are perfect for floor and desk lamp fixtures.
Candelabra LED Bulbs
Our candelabra LED bulbs offer soft and warm light output in a decorative bulb style that fits E12 lamp fixtures.
BR30 LED Lamps
BR30 lamps are ceiling lamps that fit in residential and commercial fixtures with 4-inch or wider openings.
T8 LED Lamps
Directly replace 4-ft fluorescent lamps with our T8 LED tube lights, compatible both with and without ballasts.
LED Linear Fixtures
Linear lamp fixtures in 2-ft and 4-ft lengths. Plugs into standard wall outlets nd mounts using screws or magnets.
LED Strip Lights
Bright LED emitters mounted on a flexible circuitboard. Can be cut-to-length and installed in a variety of locations.
LED Strip Power Supplies
Power supply units to convert line voltage to low voltage DC needed for LED strip light systems.