Optimizing Fire Sprinkler System Demand: Pipe Sizing

Fire sprinkler systems are critical components of building safety, designed to control and suppress
fires efficiently while minimizing damage and protecting lives. However, the demand for water flow
and pressure in such systems creates challenges for both designers and building owners, including
higher operating costs, more demanding infrastructure requirements, and potential inefficiencies.
Reducing system demand, while maintaining fire suppression performance, is therefore an essential
consideration in sprinkler system design.
This article is the first in a series exploring various strategies to reduce system demand in fire
sprinkler systems while maintaining compliance with NFPA. In this initial study, the focus is placed
on pipe sizing and its impact on flow rates and pressure requirements. Using a representative wet
pipe sprinkler system with an OH2 hazard classification, the research evaluates the effect of upsizing
pipes on system demand, with calculations performed at the base of the riser to quantify the results.
The findings highlight pipe sizing as a critical design parameter that influences system efficiency,
cost, and overall performance.
Subsequent papers in this series will delve into other important topics related to sprinkler system
demand optimization, including wall thickness adjustments (e.g., Schedule 10 pipes), effects of using
the quick response sprinklers, K-factor modifications, velocity pressure considerations, alternative
design points utilizing older editions of NFPA 13, smooth pipe types (e.g., Copper or CPVC), the
Darcy-Weisbach method, and gridded piping configurations. Each paper will explore one or more
strategies in detail, with the ultimate goal of guiding designers toward adaptable, cost-effective
solutions for both new and existing systems.