The problem here isn’t the sprinklers — it’s the cost to install the sprinklers. The cost of a few hundred feet of CPVC or PEX pipe is low. The cost of an off-t

The problem here isn’t the sprinklers — it’s the cost to install the sprinklers. The cost of a few hundred feet of CPVC or PEX pipe is low. The cost of an off-the-shelf sprinkler riser, pre-assembled, is a couple hundred dollars. The amount a Northern CA contractor will charge to install the parts is insane. (There is a problem with too little code. NFPA 13R and 13D do not clearly specify backflow protection requirements, and the California Plumbing Code, which follows UPC, only specifies it by reference to a subjective hazard level as determined by the authority having jurisdiction. This means that different local jurisdictions disagree, which creates both added complexity when designing a system and a significant risk of an actual hazardous condition existing. Situations like this are why codes exist, and IMO the code authors thoroughly dropped the ball on determining the extent to which the water in non-passively-purged fire sprinkler system is hazardous and how to prevent it from getting into drinking water. If an actual standard existed, then there could be an off the shelf compliant system, and time and money would be saved.