High-rise sprinkler systems cannot be served by a single pump: static pressure and zone management govern the design. FM Global DS 2-0 sets additional requirements alongside NFPA 14.
Zone Structure
- Static pressure limited to about 12 bar per zone
- Typically 12 to 15 storeys per zone
- Each zone has its own main, booster pump, check valve and pressure-reducing valve
- Redundancy: FM practice favours two pumps per zone
Pressure Management
- A single master PRV serving all zones is not the preferred arrangement
- A separate PRV at the entry to each zone is preferred
- FM Approved pressure-reducing valves are expected
- Annual testing, with inlet to outlet deviation kept within a defined tolerance
Booster Pump Redundancy
- Two pumps per zone, arranged in parallel or series
- Failure of one pump leaves the other available
- Sequenced starting: simultaneous starting is not permitted
- Manual shutdown after personnel have verified conditions at the pump room
Sprinkler Selection
- Quick response heads in most applications
- K115 standard spray for office areas
- K200 in storage zones such as car parks and stores
- Residential sprinklers in hotel bedrooms
- ESFR or high-K heads in atria above 12 m
Quick Checklist
- Static pressure per zone within limit
- Two booster pumps per zone for redundancy
- FM Approved PRV at every zone entry
- Annual PRV test records maintained
- Quick response sprinklers as the standard selection
- Atrium protection by ESFR or high-K heads
Frequently Asked Questions
Why is static pressure limited per zone in a high-rise system?
Water pressure rises by roughly 1 bar for every 10 m of height, so in a tall building a single riser would far exceed the rating of valves, pipework and sprinkler heads. Limiting static pressure to about 12 bar per zone forces vertical zoning, with each zone served by its own booster pump and pressure-reducing valve.
Why does FM prefer a PRV at each zone rather than a single master valve?
A single master valve creates one point of failure for the whole building and cannot correct the pressure variation that still exists within a zone. A PRV at each zone entry limits the consequences of a failure to that zone and allows the pressure to be tuned to the floors it actually serves.
Why are two booster pumps provided per zone?
Redundancy. If one pump is out of service for maintenance or fails on demand, the other remains available, and the zone is not left without pressure. Starting is sequenced rather than simultaneous, so several pumps do not start together and produce excessive inrush current and water hammer.
What sprinkler types are used in a high-rise building?
Quick response heads are the norm, with K115 standard spray in offices, K200 in storage areas such as car parks, residential sprinklers in hotel bedrooms and ESFR or high-K heads in atria where the ceiling exceeds about 12 m. The selection follows the occupancy of each area rather than the building as a whole.
SprinkCalc — Fire Sprinkler Design Across Three Standards
SprinkCalc covers hazard classification, design density and area, K-factor selection, water demand and hydraulic calculations for NFPA 13, FM Global and BS EN 12845 in a single iOS app, and exports a professional PDF report.
Download SprinkCalc on the App Store
MEP Calc — 86+ Engineering Calculators
MEP Calc bundles 86+ engineering modules in one iOS app: 21 fire calculations plus heating, cooling, HVAC, plumbing, steam and natural gas.
Download MEP Calc on the App StoreFM Global Property Loss Prevention Data Sheet DS 2-0 (Installation Guidelines for Automatic Sprinklers); NFPA 14, Standard for the Installation of Standpipe and Hose Systems; NFPA 20, Standard for the Installation of Stationary Pumps for Fire Protection.