Which sprinkler system is considered the simplest and least expensive?

The wet pipe system is recognized as the simplest and least expensive type of sprinkler system primarily due to its straightforward design and operation. In a wet pipe system, water is stored in the pipes and is immediately available to suppress a fire as soon as a sprinkler head is activated. This direct method means there are no complex components involved, like valves that need to be activated or mechanisms that control water release, which simplifies installation and maintenance.

Additionally, because the wet pipe system is commonly used in buildings that are heated properly, there is a lower risk of freezing, reducing the need for special materials or heating elements that would be necessary in systems like dry pipe or pre-action systems. This simplicity and reliability contribute to lower initial costs and ongoing maintenance expenses, making it a preferred choice in many scenarios, especially in environments where the risk of freezing is low and immediate fire suppression is desired.

In contrast, other systems like the dry pipe, pre-action, and deluge systems involve more complexity due to their operational mechanisms and are typically intended for specific situations that require additional features, thereby increasing their cost and installation complexity.