A complete worked fire alarm design for a 150,000 sq ft storage warehouse — sprinkler-led design philosophy, high-ceiling detection strategy, and the largest voltage-drop challenge in the entire program.
The project brief: a single-story, 150,000 sq ft storage warehouse, occupancy classification Storage (IBC Group S-1, Moderate-Hazard Storage), with a 32-ft clear ceiling over palletized rack storage, a small office/break room area, and a loading dock. Every prior project in this series has been detection-led — this one inverts that relationship. A Storage occupancy at this scale is overwhelmingly sprinkler-led: the automatic sprinkler system is the building's real first line of detection and suppression, and the fire alarm system's central job on the open floor is monitoring and reporting that sprinkler system's status, not driving early smoke detection across 150,000 sq ft of open storage.
This module walks the whole project end to end: why standard spot smoke detector spacing tables don't directly apply above this building's 32-ft ceiling and the real engineered response used here, why waterflow and tamper switches — usually a minor add-on elsewhere in this program — become the central device type for the open storage floor, a notification appliance layout sized to occupiable floor area rather than detector count, a fully worked NAC voltage-drop example on the longest single run in the whole program, and a Sequence of Operations table built around sprinkler flow as the dominant trigger. The full numbers, complete bill of materials, and finished worked calculations are part of the unlocked module below.