15. This cold-water supply system serves a bathroom in a multistory building. The architect
directed the piping to be installed in the wall cavities with the main branch above ceiling
level. The supply pipe construction is 4 type-L copper. The building supply is capable of
maintaining a flow rate of 10 gallons per minute. The walls contain a 6-inch cavity, and the
ceilings contain a 12-inch cavity. Consider the installation to be centered in the available
cavity space.
In the drawing, what's the height (above floor level) of the water-supply pipe where it enters
the urinals' valves?
OA. 5 feet 6 inches
B. 3 feet
C. 8 feet 6 inches
D. 7 feet