46.02
16397 Rev A Updated 03/2021 © 2021 Victaulic Company. All rights reserved.
5.0 PERFORMANCE (CONTINUED)
Hydraulic Design
The Specific Application Attic protection scheme shall be hydraulically calculated in accordance with the following
guidelines. These calculation guidelines are applicable only to the special Attic Protection scheme utilizing FL-SA/RE
and FL-SA/DS sprinklers. These requirements are based on special full scale fire testing and in no way should be utilized
when designing other than these specially listed and tested sprinklers for use in sloped combustible attic structures.
As with Hydraulic Calculations performed in accordance with NFPA 13, multiple areas of piping may need to be
investigated and multiple calculations performed should it not be readily obvious of the hydraulically most demanding
area due to non-typical pipe layout. Hose allowances must be included in the hydraulic calculations in accordance
with NFPA 13.
GABLE ROOF CALCULATION PROCEDURE
3 BRANCHLINE DESIGN - WET SYSTEM
3 Branchline Design – Wet System
Perform the following 2 calculations:
Calculation #1: Calculate the 5 most hydraulically demanding sprinklers consisting of 5 FL-SA/RE (Ridgeline)
sprinklers. Minimum sprinkler flow is 20 gpm per sprinkler. See Figure 16A.
Calculation #2: Calculate the 5 most hydraulically demanding sprinklers consisting of 2 FL-SA/DS (Downslope)
sprinklers and 3 FL-SA/RE (Ridgeline) sprinklers. Minimum sprinkler flow is 20 gpm per sprinkler. See Figure 16B.
Note: If additional sprinklers are required beyond an obstruction, calculate up to 2 additional sprinklers beyond the
obstruction. See Figure 16B.
FIGURE 16A
DORMER OPEN TO ATTIC SPACE
FIGURE 16B
2 ROW DS SPRINKLER
(HIP SHOWN AT CORNER)
FIGURE 16: HYDRAULIC CALCULATION REQUIRED FOR WET 3 BRANCHLINE SYSTEM
12
