Corner LED Profiles — How to Make a Light Line in the Corner of a Stretch Ceiling

What the 2K-Trade catalogue does not have — and how to solve it differently

By “corner LED profiles” most shops mean a small aluminium profile with a triangular cross-section (16×16, 18×18 or 20×20 mm), glued under a kitchen shelf or in the corner of a wardrobe. 2K-Trade does not sell such profiles, and we will not pretend otherwise. The catalogue covers aluminium profiles for stretch ceilings, and there the “light in the corner” task is solved differently: the LED channel is part of the profile that the ceiling membrane hooks into. Below we show which catalogue profiles do this job and how they differ.

Where the light in the corner of a stretch ceiling comes from

In a stretch ceiling, a light line is created where the wall meets the ceiling, between two membranes or in a niche at the wall. The profile then does two jobs at once: it holds the harpoon of the membrane and houses the LED strip closed with a diffuser. Instead of a glued-on corner profile, a ceiling profile with an LED channel is installed, and the corner of the room is made from two lengths of profile butt-joined together. The choice depends on where the light is to go: in a line along the wall, in a niche at the wall, in a transition between ceiling levels, or continuing onto a plasterboard wall.

GAMMA series — a light line along the wall or between membranes

Two naming systems coexist in the 2K-Trade catalogue. In the CLASSIC and COMFORT mounting profiles, the number in the name is the approximate mass of one running metre in grams. In the GAMMA and GK LINE IN profiles, the number is the approximate width of the light line or slot in millimetres — not the width of the LED strip. The channel is much wider than a strip: GAMMA 20F and GAMMA 20 SLIM have a channel of approx. 17 mm (one strip), GAMMA 30, GAMMA 30 SLIM and GAMMA 30 VERT approx. 31 mm (two strips side by side), and GAMMA 50 approx. 45.6 mm (up to three 12 mm strips).

All GAMMA profiles are 2 m long and are fixed to the structural ceiling on steel angle brackets; they have no mounting holes, so these are drilled on site. GAMMA 20 has one upper mounting chamber, GAMMA 20F has two side chambers, so it can be screwed directly to the base ceiling. GAMMA 30 HP has higher sides that make tensioning the membrane easier and can additionally be glued to the wall. The SLIM versions (height approx. 31 mm) are used where there is little space above the ceiling.

For a corner, the key profile is GAMMA 30 VERT: its vertical side walls make it easier to join profiles at a right angle and to run a continuous light line from the wall onto the ceiling. The full overview of the series is in the article LED Strip Profiles: Types, GAMMA Series and Selection Guide.

GAMMA 10 is a separator: it divides two ceiling membranes where a gap without light is needed. It is not a lighting profile and no LED strip is installed in it.

CONTOUR and CONTOUR-PRO LUX — contour light along the wall

The CONTOUR (white RAL-9016, approx. 285 g/m) and CONTOUR-CLASSIC (approx. 300 g/m) profiles are fixed to the wall. The LED strip shines through the stretch ceiling membrane, and the profile sits tight against the wall thanks to a PVC seal. Both profiles are used only with light-coloured membranes.

CONTOUR-PRO LUX (white, black or unpainted, approx. 300 g/m) forms a niche for the LED strip at the wall, closed with the flexible DF-CONPL diffuser — the ceiling looks as if it were floating. The CONTOUR-PRO LUX-SU version has mounting holes and is fixed to the ceiling. All CONTOUR profiles are sold in 2 m lengths.

SIGMA-NEO LED — a niche with an LED channel

The previous version of this article called SIGMA-NEO LED a “corner profile”. That was imprecise: it is a niche profile with a channel for an LED strip. SIGMA-NEO profiles are used to build niches and multi-level ceilings — SIGMA-NEO LED additionally takes an LED strip, so a backlit niche at the wall or a backlit transition between levels is made without a separate lighting profile. Mass approx. 730 g/m, length 2 m, fixed to the ceiling on angle brackets, unpainted. SIGMA-NEO PLUS gives clean transitions between levels without gluing the membrane at internal corners.

GK LINE IN 20 and 30 — when the line must continue onto a plasterboard wall

If the corner is formed by a stretch ceiling and a plasterboard wall, the light line is continued with the recessed profile GK LINE IN 20 (light slot 20.1 mm, width 62.7 mm) or GK LINE IN 30 (slot 34 mm, width 73.6 mm). Both are 14.4 mm high, have a 12.4 mm flange, weigh approx. 0.35 / 0.40 kg/m, come in mill finish and 2 m lengths (packed in 10 m). These are the only two models in the series. GK LINE IN 20 takes the same diffuser as GAMMA 20, so the line from the stretch ceiling continues onto the plasterboard wall with no change in appearance. More in the article LED Profiles for Plasterboard: GK LINE IN Series.

Which profile for which corner — overview

LED strips, diffusers and power supply

The LED strips in the catalogue run on 24 V and are 8, 10 or 12 mm wide, so they fit the channel of every profile in the overview. For dry interiors IP20 is enough — for example the 140 LED/m 24 V IP20 strip (4.8 / 9.6 / 14.4 W/m; 3000, 4000 or 6000 K) or Hi-Eff 192 LED/m (14 / 20 W/m). In a kitchen or bathroom the 140 LED/m 24 V IP65 strip (9.6 W/m, 4000 K) is used, in which the LEDs are potted in resin against dust and splashes. Check the luminous flux in the technical data of the specific strip — we do not give indicative values here.

Diffusers are matched to the profile: DF-G.20 for GAMMA 20, 20F, 20 SLIM and GK LINE IN 20; DF-G.30, DH-G.30 and the black DH-G.30.BL (a black line effect when the light is off) for the GAMMA 30 family; DH-G.50 for GAMMA 50; DF-CONPL for CONTOUR-PRO LUX. 24 V DC power supplies from Mean Well and Eaglerise are placed where they remain accessible after the ceiling is closed, e.g. in an inspection hatch or a cabinet.

Projects: LED niche and linear light

Two installations by the installation partner GRAF Ceilings & Walls (materials from the 2k-trade.com catalogue) show both variants. Ceiling under a built-in wardrobe in a child’s room: BAUF Glossy Graphite membrane, reinforcements for the wardrobe, shadow-gap profile and an LED niche; 2 days of work, price from 180 PLN/m². Acoustic ceiling in a lighting showroom: CLIPSO Acoustic White Matt fabric in one piece hides ventilation ducts and 48 V magnetic tracks; a suspended profile with a linear LED light; 5 days (4 + 1 for 16 lamps), from 400 PLN/m². More projects: sufitynapinane.eu/realizacje.

Frequently asked questions

Does 2K-Trade sell 16×16 or 20×20 mm corner profiles for furniture?

No. The catalogue contains aluminium profiles for stretch ceilings and plasterboard constructions. Light in the corner between wall and ceiling is made with profiles that have an LED channel: GAMMA, CONTOUR, SIGMA-NEO LED or GK LINE IN.

Which profile should I choose when the light line runs from the wall onto the ceiling?

In a stretch ceiling — GAMMA 30 VERT, whose vertical side walls make right-angle joints easier. If the wall is plasterboard, the line is continued with GK LINE IN 20, which takes the same diffuser as GAMMA 20.

What does the number in GAMMA 20, 30 and 50 mean?

The approximate width of the light line in millimetres, not the strip width. The channel is wider: approx. 17 mm in GAMMA 20F and 20 SLIM, approx. 31 mm in GAMMA 30, 30 SLIM and 30 VERT, approx. 45.6 mm in GAMMA 50.

Can an LED strip be installed in GAMMA 10?

No. GAMMA 10 is a separator dividing two ceiling membranes. Light lines are made with GAMMA 20, 30 and 50.

Which LED strip is suitable for a line in the corner?

A 24 V strip 8, 10 or 12 mm wide. In dry rooms IP20 is enough; in a kitchen or bathroom, IP65. Power and colour temperature are chosen for the project; the luminous flux is in the technical data of the strip.

Questions about choosing a profile for a specific corner: contact the 2K-Trade technical team.

Author: MB 2K-Trade