How to Choose an LED Wall Washer for Facade Lighting
Five decisions determine whether your facade lighting works or fails: wattage, beam angle, mounting distance, IP rating and colour temperature.
The Five Decisions
A wall washer specification requires five decisions that interact with each other. Getting them in the right order matters:
Mounting distance
How far from the wall can you mount the fixture?
Beam angle
Determined by mounting distance and wall height.
Wattage
Determined by distance and required illuminance.
IP rating
Determined by exposure environment.
Colour temperature
Determined by building type and visual intent.
Decision 1 — Mounting Distance Comes First
The most important starting question is not how many watts, but where the fixture can be mounted. Mounting distance drives beam-angle selection, which drives wattage. Starting with wattage leads to the wrong specification almost every time. Available positions depend on the building architecture: parapet width, window mullion depth, soffit projection, podium ledge width or ground-level setback. Map the available mounting positions before selecting any fixture parameter.
Decision 2 — Beam Angle
Once mounting distance is established, beam-angle selection follows a straightforward rule: the further from the wall, the narrower the beam. A narrow beam concentrates light, which is necessary at longer distances to maintain adequate illuminance; a wide beam spreads light, appropriate at short distances for even coverage without hotspots.
| Mounting distance | Recommended beam | Wall coverage height | Typical application |
|---|---|---|---|
| 0.3–0.8 m | 40°–60° | Up to ~4 m | Retail frontage, heritage texture, podium level |
| 0.5–1.5 m | 25°–40° | Up to ~10 m | Hotel facade, commercial building, mixed-use |
| 1.0–2.5 m | 15°–25° | Up to ~15 m | Large commercial facade, longer parapet setback |
| Above 2.5 m | 10°–15° | Above 15 m | Switch to architectural spotlight |
Decision 3 — Wattage
Wattage determines luminous flux. At a fixed beam angle, higher wattage produces higher illuminance on the wall surface; at fixed wattage, a narrower beam concentrates the same output over a smaller area. For most architectural facade applications, target illuminance is 50–150 lux on the wall surface; premium hotels and heritage buildings typically specify 30–80 lux for a more refined result.
| Mounting distance | Wattage range | TPK recommendation |
|---|---|---|
| 0.3–0.8 m | 18W–38W | LWW-PZT-W38A (38W) |
| 0.5–1.5 m | 38W–55W | LWW-PZT-W38A / LWW-WZB-W55 |
| 1.0–2.5 m | 55W–80W | LWW-WZB-W55 / LWW-OP-D80 |
| Large scale / bridge | 80W–150W | LWW-OP-D80 / LWW-ROWS-W150 |
Decision 4 — IP Rating
For all permanent outdoor installations, specify IP67 as the minimum. IP67 ensures the fixture survives heavy rain, typhoon-condition wind-driven water, high-pressure facade cleaning and repeated thermal cycling across its rated life. For coastal and marine environments, IP67 is necessary but not sufficient — specify marine-grade corrosion protection for the housing in addition to the IP rating. See the IP rating guide for a breakdown by application.
Decision 5 — Colour Temperature
2700K warm white suits heritage buildings, luxury hotels and hospitality venues, rendering stone, timber and terracotta naturally. 3000K warm-neutral is the most versatile specification — warm enough for hospitality, clean enough for modern commercial. 4000K neutral white suits corporate offices, modern commercial towers and civic architecture. RGBW dynamic colour is for shopping centres, entertainment venues and landmark buildings, and requires DMX512 control.
Recommended Products by Application
LWW-PZT-W38A
Hotel facades, retail frontage, heritage texture, close-range applications up to ~8 m.
LWW-WZB-W55
The most specified model — medium to large commercial facades, hotel exteriors and RGBW colour applications.
LWW-ROWS-W150
Large-scale commercial facades, bridge deck fascias, infrastructure and large architectural structures.
When to Switch from Wall Washer to Spotlight
Wall washers are optimised for surfaces within 2.5 metres. When the required throw distance exceeds this, or when building height exceeds 10–12 metres, an architectural spotlight with a narrow beam angle delivers better illuminance control. TPK's SP-DKP-F170A (170W), SP-MEGA-F310A (310W) and SP-MEGA-F620A (620W) spotlights cover medium to extreme long-throw applications.
FAQ
What is an LED wall washer and what is it used for?
An LED wall washer is a directional outdoor fixture designed to illuminate a vertical surface — a building facade, bridge structure, garden wall or architectural feature — with even, controlled light. Unlike a floodlight, it uses an asymmetric beam pattern optimised for washing a flat or curved surface uniformly from close range.
How far should LED wall washers be mounted from the wall?
0.3–0.8 m: 40°–60° beam, covers up to ~4 m. 0.5–1.5 m: 25°–40° beam, the most common range for hotel and commercial facades up to ~10 m. 1.0–2.5 m: 15°–25° beam for taller facades. Above this, architectural spotlights are specified instead.
What wattage LED wall washer do I need?
0.3–0.8 m: 18W–38W. 0.5–1.5 m: 38W–55W (most common). 1.0–2.5 m: 55W–80W. Large facades or bridges: 80W–150W. Landmark towers requiring very long throw: architectural spotlights from 170W–620W.
What is the difference between a wall washer and a floodlight?
A wall washer has an asymmetric beam pattern that illuminates a vertical surface evenly from close range. A floodlight produces a broadly symmetrical beam for area lighting over distance. For facade lighting, wall washers give even coverage without the hotspots, scalloping and glare floodlights create close to a building face.
Can I get IES photometric files for TPK wall washers?
Yes. IES files are available for all TPK wall washer models and are compatible with DIALux, AGi32 and Relux. Download from the Resources page or contact ES2@topkinglite.com. TPK also provides photometric simulation as part of the project engineering consultation service.
