Vertical illumination emphasises the walls - or other room limits - in terms of their physical makeup.
The room is made to look bigger by brightening the wall faces.
Point-form light sources make the wall surface much more vivid while with linear luminaires a higher uniformity is achieved.
As the room height increases the distance of the luminaire to the wall must be increased.
The reduction of the mean illuminance in higher rooms can be compensated for by having a higher lamp power and by increasing the number of luminaires. Wallwashing only produces an even brightness on matt surfaces.

Lighting criteria for high walls
- uniformity of the lighting
- the choice of lamp determines the light colour and colour rendition
Wall 5m Position