Reviewed: Cove lighting

LEDs have made cove lighting simpler and cheaper. But there are huge differences between the various systems. The Lux technical team checked out eight leading brands. Here’s our verdict…

Coves are not always straight! Search for cove lighting and you will find hundreds of almost identical aluminium extrusions with LEDs inside. You might even find some T5 fluorescent and cold cathode (“neon”) systems.  But nowadays, there is a trend for architects to use more and more flowing lines in their buildings and so this article reviews cove fittings which can also be used on curves and in archways.

We have included a lot of different types and style of luminaire which can illuminate a cove. Some luminaire types will be more suited to your particular needs than others.

Many flexible systems will only bend in one plane – imagine the way you can bend a thin steel band or strip. Other systems can bend in two planes. A further refinement is that some LED modules can also be tilted or rotated. Obviously, the more complex systems cost more and they are often physically larger.

When deciding which system to choose, one of the first things to consider is whether you want to produce simply a glowing line of light or whether you want sufficient light output to give a useful level of illumination in the space. It is worth remembering that T5 fluorescent lamps emitted well over 2,000lm/m (700lm/ft) and so they could produce plenty of indirect illumination. Obviously, fluorescent lamps can only be used on straight lines. Flexible incandescent cove systems might only produce a tenth of that amount of light.

Achieving uniform lines of light and a smooth gradation of brightness, is also important. You need to avoid 'hot spots' although this can sometimes be overcome by locating the LEDs quite some distance from the illuminated surface.

Lastly, consider whether you need accurate colour rendering. For most applications, a CRI of 80 is sufficient, but some of the cove lighting systems we have reviewed offer a CRI of 90 or even higher.

Cove lighting can make an important difference (good or bad) to the appearance of a space so I would always recommend a trial or mock-up before ordering.

 

 

Burcridge 

This system is ideal if your existing space does not already have a cove built in. The system comprises of a wide range of straight and bendable galvanised steel profiles in various dimensions. The profiles are then fixed to the structure of the building and plastered over. A flexible LED strip suited to that particular profile can then be quickly fitted in position. The LEDs are offered in a range of different sizes and outputs.  This can be as much as 1,470 lm/m (445 lm/ft) with a CRI of 95. It is available in 3000K and 4000K.

Since the profiles are factory made, you can achieve more accurate and precise shapes than constructing the coves on site.

A useful accessory is that Burcridge can supply a thin flexible magnetic strip. The LED tape can be stuck to the strip and the magnetic side is used to precisely locate it in position on the steel profile.

  • Lux rating: A complete cove system


 

Cooledge Line 

This is a Canadian company and we obtained our samples through Atrium Lighting in the UK.

The Cooledge product is unlike anything else you will have seen. In essence, it is a wafer-thin ‘copper paper’ made as a long ribbon either 56 mm (2.2”) or 96 mm (3.8”) wide. It is almost as flexible, and in as many directions, as a regular sheet of paper. This means you can apply it to almost any shape or form of surface.

Its thinness and closely positioned LEDs means that you can fit it behind a diffuser and achieve uniform lighting with a depth of less than 25 mm (1”).

Typically, the Cooledge Line emits between 1,500 and 2,800 lm/m (450 – 850 lm/ft) depending on the width used. The colour temperature, CCT, is available in 2700, 3000, 3500, 4000 and 5700K. CRI is greater than 90. It’s also available in tile shapes which are colour tunable and exterior versions.

  • Lux rating: Unique applications


 

 

KKDC UNI P-FX4

I wouldn’t normally include an LED tape in this review of cove lighting because regular tape only bends in one direction. However, KKDC have cleverly overcome the problem by inserting regular V-shapes in the tape so that it can flex in two planes. Another reason is that this tape is available in nine different colour temperatures, with a CRI of over 90. Many lighting designers speak highly of the colour precision you obtain with KKDC LEDs.

The 3000K version emits 1,450lm/m (440 lm/ft). As with other tapes, there is no beam control and so the light is emitted over approximately 140 degrees.

  • Lux rating: Good CRI and range of CCTs

 

 

 

Mike Stoane Billet

The main characteristic of this system is that the 52mm x 12 mm (2” x 0.5”) modules are magnetic. You could spiral them around a steel tube or duct. Coving and plaster profiles often have a galvanised steel support or/ backing and so the Billet can simply be laid in place and adjusted precisely. VHB adhesive mounting pads are an option.

As you would expect from a Mike Stoane product, it is beautifully designed and precision manufactured. It is flexible whilst being solidly constructed and made with fine tolerances. If you want an industrial look to your architecture, it would be a waste to conceal it behind a cove.

  • Lux rating: Deserves to be seen

 

 

Moda Mini Cove

This, again, is a US company and we obtained our samples through A.C. Special Projects in the UK. The smallest LED module is 300 mm long (1ft) and so it is less flexible than some of the other products reviewed. However, each module can rotate 180 degree to you can direct the light beam to where you want it.

An advantage of the Moda system is that each module has its own fully dimmable on-board driver. Both the supply and interlinking cable are mains voltage. This means you can run lengths from 36 to 109 m (120 to 360 ft) from a single feed. Moda claims that the driver can also smoothly dim from 100 per cent to 0 per cent output without any flicker and every module would be synchronised.

The LEDs have excellent colour rendering with a CRI typically between 94 and 98 with none of the R1 to R15 values less than 90. The Moda data sheet includes the TM30 measurements and GAI values.

One other reason for considering the Moda Mini Cove is the option of high light output. The most powerful version emits almost 4,000 lm/m (1,200 lm’ft).

  • Lux rating: High output for large radius coves

 

 

Osram LINEARlight FLEX Diffuse 400

This is a bendable, rectangular-section strip of soft, tactile plastic material. It measures just 10mm high x 14mm wide (0.4” x 0.6”). The light emitting surface is diffuse and the strip is available is either side or top bending versions. The light output is totally uniform and it is ideal where you want long, continuous lines. It would also be ideal for handrails and stairs. Its continuous rectangular shape means that you can slot it in to an aluminium extrusion to achieve a straight run and then immediately turn it into a curve without any interruption or break.

You could install the strip behind coving but it’s certainly attractive enough to be seen in full view. There is a low power version which emits 400 lm/m (120 lm/ft) and a higher power version at 800 lm/m. The CRI is greater than 80 and the strip is available in versions from 2700K to 6500K. Six colours are also available. These include yellow and orange which are rarely an option with LED sources.

  • Lux rating: Perfect for lines of light

 

 

Radiant 3D LED Flex 40

This is Radiant’s flagship product and best-selling luminaire in all its forms. It is bigger than many cove systems but much more powerful. The LED modules are 100 x 40 x 33 mm (4” x 1.6” x 1.3”). A clever feature of the design is that the LEDs themselves are equidistant both inside and also between modules so achieving totally even lines of light. The modules rotate and the interlinking ball-joints bend in two planes so there is a huge degree of flexibility.

This system is also ideal where you want functional levels of lighting in the space. The 3D LED Flex 40 emits almost 3,500 lm/m (> 1,000 lm/ft). This is at least 50 per cent more light output than a T5 linear fluorescent lamp. There is a wide range of optical accessories and snoots available. If this system is more than you need, there is a smaller Euclid 20 range which is more suited to retail or restaurant applications.

  • Lux rating: Comprehensive and powerful

 

 

Tempo C3S

Whilst Tempo doesn’t have any representation in Europe, its products are available in the USA and elsewhere in the world. 

The company has a large range of rigid and flexible, (the S suffix denotes serpentine), cove systems. The C3 is the smallest and is based on individual grey plastic modules which are 75mm long and 23 mm wide (3” x 0.9”). Each module contains six LEDs and these modules are linked together with a flexible 24V cable. The modules have a lightly frosted lens and there is an option of a more heavily diffusing cover.

A useful feature of this product is that the colour temperature, CCT, options available range from a cool 5000K to a really warm 1600K.
Whilst the unit performs well in use, on a desk top, the modules appear to be more lightly constructed than some other systems.

  • Lux rating: Very flexible

 

 

  • See the very latest cove and other LED lighting systems at the lightspace dot london 2017 and LuxLive 2017 exhibitions, both of which are co-located at ExCeL London on Wednesday 15 November and Thursday 16 November 2017. Entry is free if you pre-register HERE.