Kidde Fire Systems DS Series, Application Manual

Page: 17 / 42

July 2016 -15- K-76-1000
Solid Joists
When spacing heat detectors at right angles to the solid joists, do not exceed 50-percent of the listed
spacing and mount the detectors at the bottom of the joists.
Figure 7. Heat Detector Spacing for Solid Joists
Figure 8. Reduced Heat Detector Spacing for Solid Joists Construction
Exposed Beams
Exposed beams may impede the flow of fixed temperature heat detectors. Beams are defined as solid
structures extending 4 in. (100 mm) or more down from the ceiling. Beam spacing depends on the depth
of projection from the ceiling and the center-to-center spacing between the beams.
D. Depth
W. Spacing between joist 1. Ceiling
2. Detector 3. Joist
1. Heat detector
2. Joist S = Listed spacing between DS-HFS detectors
= 50 ft. (15.2 m)
W
D
1
2
3
> 4 in.
(100 mm)
1/2 S
1/2 S
1/2 S
1/2 S
1/4 S
1/4 S
S
1
2