This case documents media facade addressable led strip lighting on a 6-storey commercial building in Trondheim, facing a square used for evening markets. The client had priced LED video panels; we proposed a light-point matrix — Approx. 428 m of addressable strip on 22 vertical mullion lines, sized by viewing distance, not resolution ambition. Part of our architectural linear LED lighting work.
Why This Is a Grid of Points, Not a Screen
People view from Approx. 40 m to Approx. 90 m across the square. At Approx. 40 m the eye’s one-arcminute limit is Approx. 11.6 mm, so a 100 mm pitch is comfortably resolvable — roughly 8.6 arcminutes. Viewers see discrete points of light, deliberately. Media facade addressable led strip lighting at this pitch is not a poor screen but a different medium; pretending otherwise is how these projects disappoint.
What decides content is the aspect ratio of one pixel. Vertical pitch is 100 mm, set by the strip; horizontal pitch is Approx. 1,360 mm, set by the mullion grid — 22 lines, so no new fixings above eye level. The canvas is 22 × 160, pixels Approx. 13.6 times wider than tall. Vertical wipes and colour fields read well; text is impossible, and we said so before the content brief, not after.
Products Used, and What Sets the Pitch
| Zone | SKU | Specs | Approx. Use |
|---|---|---|---|
| 22 vertical mullion lines | ES-WS2811-30-12V | WS2811 addressable RGB, 30 LEDs/m, 10 mm, DC12V, CRI 80 — IP20 as supplied, sleeved to IP67 | Approx. 352 m |
| Parapet band, roof curves | ES-NEON-PIXEL-01 | Addressable RGBIC neon flex 6 × 12 / 8 × 16 mm, 12V/24V, IP67, 120 LEDs/m | Approx. 60 m |
| Entrance soffit | ES-COB-576-10MM-RGBIC | RGB IC addressable COB, 576 LEDs/m, 10 mm, 12V/24V, CRI 90, IP20 | Approx. 16 m |
The 30 LEDs/m part is not a cost compromise — it produces the pitch. A WS2811 IC drives three LEDs as one pixel, so 30 LEDs/m gives 10 pixels per metre: a 100 mm pitch. The 60 LEDs/m version gives 50 mm, doubling pixel count and data budget for nothing visible at that distance. The parapet needs addressable neon flex: those roof curves are Approx. 240 mm radius and bend in the plane of the strip’s width, where a PCB strip cannot go. It is also natively IP67, unlike the sleeved verticals — the honest reading of waterproof addressable strip. Dotless RGBIC COB appears only at the entrance soffit, where pedestrians pass within Approx. 1 m and points would read as a fault; under a soffit, IP20 holds.
Splitting the Canvas, and the Arithmetic That Forced It
WS2811 runs at 800 kbit/s and needs 24 bits per pixel, so each pixel costs Approx. 30 µs of frame time. That one number set the control topology for this media facade addressable led strip lighting:
- One data line for Approx. 3,520 canvas pixels takes Approx. 106 ms per frame — Approx. 9 fps, and motion tears. This is the failure mode behind most disappointing pixel facades: arithmetic, not controller brand.
- Universe A, bottom third: 8 lines, Approx. 1,280 pixels, Approx. 38 ms — Approx. 26 fps.
- Universe B, middle third: 8 lines, Approx. 1,280 pixels, same budget, main motion field.
- Universe C, top third: 6 lines, Approx. 960 pixels, Approx. 31 fps, slow ambient scenes.
- Universe D: parapet band and soffit, slow gradients only, tied to retail hours.
All four run from one master clock, so a wipe crosses the facade as one motion, not four boards taking turns. Show data is DMX512-A per ANSI E1.11, so the developer can bridge to a house desk later. The pixel players came from the AV integrator, not us — our range covers IR and RF colour controllers, not multi-universe players — worth knowing before reading addressable controller guidance. We supplied strip, pixel map and injection layout.
Power, Ingress and What Got Measured
- Every circuit is 12V SELV per IEC 61140. Nothing reachable from the square exceeds 12V.
- Full-white connected load Approx. 2.5 kW. Content caps at 50%, so working draw sits near Approx. 1.1 kW. Outdoor-rated 12V supplies live in a service riser.
- Injection every Approx. 4 m off a riser bus, four verticals per bus. No tap sits outside the envelope — those joints fail in year five.
- Measured tail drop on the longest vertical, Approx. 16 m: Approx. 2.9%.
- Sleeved verticals were immersed at Approx. 1 m for 30 minutes before shipping — the IPX7 procedure in IEC 60529, not spray, which proves a different rating.
- Frame-time deviation between universes over four hours: Approx. 3 ms — a wipe reads as one gesture.
Four Notes if You’re Specifying a Media Facade
- Set pitch from viewing distance, then check what pixel shape the mullion grid gives. A 13.6:1 pixel rules out text before content is commissioned.
- Do the frame-time arithmetic before choosing a controller count. Media facade addressable led strip lighting fails on frame rate far more often than brightness.
- Keep every injection tap inside the envelope.
- Check whether the strip is natively IP67 or sleeved to get there, and test sleeving by immersion, not spray.
Senfey is a Chinese LED strip manufacturer established in 2013, based in Shenzhen, with in-house SMT and silicone extrusion lines producing Approx. 1.2 million metres per month across COB, SMD, addressable and neon flex. See our architectural facade lighting range or request a media facade quote.
