Interior Lighting for Designers

Linear wall-washers
Continuous slotsare located in the ceiling
next to the wall and can enclose other kinds
of wall-wash luminaires (figure 12.29). The
ceiling is de-emphasized, while vertical sur-
faces such as walls, murals, and draperies
are given prominence.

Incandescent systems. Wall-washing may
also be provided by individual directional
lamps mounted on a repetitive spacing in a
continuous, linear raceway. These systems
require the use of a directional point source
that is able to project its light over the height
of the wall (figures 12.30 and 12.31). The
multiple beams of the repetitive lamps over-
lap, producing uniform brightness along the
breadth of the wall.

Lamps are typically mounted close to the

surface being lighted. The distance from the

lamps to the wall and the distance between

the lamps are determined by a full-size mock-

up. Excessive lamp spacing will cause scal-

lops. To minimize scallops, the following max-

imum lamp spacing serves as a guide:

For PAR flood lamps:

maximum spacing is 0.8 × the

distance to the wall

For R flood lamps:

maximum spacing is 1.0 × the

distance to the wall

Fluorescent lamps. The minimum discern-

ible variation in luminance is approximately

2:1. Even with the aid of precisely formed

LUMINAIRES

Figure 12.29T8 fluorescent wall-washer with compound-contour reflector in continuous slot.