Narrow COB LED Strip Lighting for a Full Apartment Fit-Out in Kraków

A Joiner-First Project, Not a Lighting-First One

The client is an interior contractor who runs his own joinery workshop. He specifies cabinet narrow cob led strip lighting the way he specifies hinges — the strip has to fit the groove and hide behind the shadow line, not the other way around. The grooves were already cut when we arrived: 10 mm wide × 12 mm deep at every shelf underside, wardrobe interior and toe-kick. Any strip wider than 10 mm was off the table on day one.

• Kitchen — under-cabinet worktop lighting (Approx. 5.2 m) plus toe-kick (Approx. 4.6 m).
• Walk-in wardrobe — six vertical rails, Approx. 1,940 mm of clear groove each.
• Living room — a 4.8 m oak wall split into 12 bays, Approx. 380 mm of clear width per bay.

Project at a Glance

Two SKUs Did the Whole Apartment

1. ES-COB-320-8MM-12V (kitchen worktop and toe-kick, 4000K) — an 8 mm strip drops into a 10 mm groove with 1 mm clearance each side, the tolerance the joiner wants for adhesive spread. 12V was chosen only because the kitchen already had a 12V rail feeding under-cabinet accessories.
2. ES-COB-480-24V-8MM (wardrobe rails and living-room bays, 3000K) — same 8 mm width, but 480 LEDs/m gives a smoother wash down a 380 mm bay without a diffuser upgrade. Both SKUs are CRI 90, so oak reads the same colour in all three rooms.
3. Narrow side-lip aluminium profile, sourced to the joiner’s own groove — the side lip stops him crushing the strip when he clips the diffuser in.
4. 24V SELV drivers in the utility cupboard, SELV per IEC 61140 — never behind the joinery, always behind an accessible service door.

See our home-decor COB range for the wider family; our wide COB LED strip guide covers why we stayed at 8 mm.

The Cutting Point Problem, Solved Once in the Workshop

The hard part of cabinet narrow cob led strip lighting is not the strip — it is the cut point. Every joiner asks whether he can cut anywhere; the honest answer is no. These reels carry a marked cut interval of Approx. 25 mm, and neither the 1,940 mm rail nor the 380 mm bay is a clean multiple of it — our guide to cutting COB LED strip explains why the interval exists.

Asking the joiner to align every groove to a cut mark is unrealistic once the CNC file is signed off, so we did the arithmetic once and delivered a numbered, pre-cut kit:

• Kit A — 6 × 1,925 mm for the wardrobe rails. The 15 mm shortfall hides behind the top rail bracket.
• Kit B — 12 × 375 mm for the living-room bays. The 5 mm gap sits behind the bay-end trim.
• Kit C — kitchen running lengths, cut on site by our electrician against the marked interval.

Every segment went into a labelled bag naming its groove. The joiner never picked up a pair of scissors.

What the Apartment Measured at Handover

Handover was set for the day the profile adhesive finished curing:

1. Approx. 26 m of cabinet narrow cob led strip lighting across three rooms and three groove locations.
2. Zero visible cut edges — every joint sits behind a bracket, a shadow line or a toe-kick lip.
3. Kitchen worktop measured Approx. 340 lx at the counter at 100%, dimmable to Approx. 15%. EN 12464-1 asks 500 lx of a commercial kitchen; a domestic one sits outside its scope, and the client chose the lower level deliberately.
4. Colour consistency: single-batch reels, ΔCCT held within Approx. 100 K room to room.

What This Job Would Have Cost If We’d Ignored the Groove

Had we specified a 12 mm strip out of habit, the joiner would have re-cut every groove — two days of labour, plus re-sanding the oak. Four things to settle before quoting a residential joinery package:

• Ask for the groove size before the strip width. 8 mm in a 10 mm groove is the safe default; 5 mm is only worth it for glass-shelf edge-lit work.
• Do the cut-length maths at the office, not in the van. A numbered pre-cut kit saves more time than any faster adhesive.
• Keep drivers behind service doors. One buried behind glued oak is not a warranty you want to honour.
• Match CCT bins across rooms even when the nominal Kelvin differs. Nominal 3000K reels drift by roughly ±150 K, which the eye reads as a colorimetry fault rather than a batch difference.