How to Build a Fire Sprinkler System 101 for Property Owners

Posted by Michael Taylor on Nov 29, 2021 2:24:00 PM

When building or remodeling a property, it can be overwhelming to understand the intricacies of building out the different systems required for that facility to operate properly. The fire sprinkler system is no exception. Just like HVAC, electric, or plumbing systems, the fire sprinkler system must meet minimum standards and requirements for the owner or occupants to be permitted to use the facility. 


Facilities That Require a Fire Sprinkler System

In general, the National Fire Protection Association (NFPA) outlines the minimum standards and requirements regarding fire sprinkler systems. Depending on the type of building being built or bought, an owner’s facility may fall under NFPA 13 for new builds, NFPA 25 for existing buildings, or NFPA 13R for residential buildings. While the NFPA codes are the guidelines for fire protection, the responsibility of enforcing and setting the standard for your fire sprinkler system is on the Authority Having Jurisdiction (AHJ). Your AHJ varies depending on your building location and type. Typical AHJs include fire marshals, local officials, or approved professional engineers. The AHJ ultimately decides if the fire sprinkler system is up to code for its designed function.


Types of Fire Sprinkler Systems

Now that we’ve covered where and who your system requirements will come from, we can now discuss how systems are designed with these standards in mind. In a new build, your sprinkler system will typically be designed by an engineer or a licensed fire sprinkler contractor. The type of system they design depends on a few factors: the use type of the facility, estimated hazard level, and environment of the sprinkler system. These considerations help determine sprinkler head density, type of pipe, and many other components that go into designing the sprinkler system.

The most commonly used sprinkler system is a wet pipe sprinkler system, which always has water in its piping and dumps the water through a sprinkler head when it opens due to heat. Wet pipe sprinkler systems work great in most facilities where the pipe is located in a conditioned space and isn’t subject to freezing conditions. 

In situations where the piping of a fire sprinkler system is exposed to subfreezing temperatures, like a parking garage, attic system, or an open canopy, a dry pipe sprinkler system may be necessary. A dry pipe sprinkler system holds water back behind a valve using air pressure on the inside. If a sprinkler head on the system opens, it will dump the air pressure and open the valve to let water in to suppress the fire. 

There are also more specialized systems such as pre-action and deluge systems. A pre-action system is a variation of a dry system, but the valve is controlled electronically and is activated by a heat or smoke detector. This type of system is typically used in applications where false trips are extremely detrimental to facility function, such as freezer warehouses and data centers. A deluge system is another variation of a dry pipe sprinkler system that dumps water from all of its sprinkler heads when activated. Facilities where the rapid spread of fire is a concern, like aircraft hangars and facilities storing explosive or highly flammable materials, commonly use a deluge system. Knowing your building’s purpose and function can help determine which fire sprinkler system will work best.


Maintenance of a Fire Sprinkler System

After your system is designed and installed, the owner must then be mindful of the required maintenance of the fire sprinkler system. Required maintenance will depend on the type of system installed, the local code requirements, and insurance provider requirements. Maintenance can be broken out into monthly, quarterly, and annual tasks. More involved maintenance processes include full system trips, which occur every three years on a dry or pre-action sprinkler system, and internal inspections on a wet pipe sprinkler system every five years. It is highly recommended that a property owner work with a fire sprinkler service contractor to ensure that the system is maintained correctly.


Life Expectancy of a Fire Sprinkler System

Even with proper maintenance, it is important to understand that a basic sprinkler system does have an expected useful life since most are affected by oxygen corrosion. Dry and pre-action systems maintained by an air compressor have a typical life expectancy of about 15 years, which varies depending on piping material and pipe wall thickness. The life span is shorter when using galvanized pipe and longer when using a thicker pipe. The use of a nitrogen generator can drastically reduce oxygen corrosion and significantly extend the life expectancy of a dry or pre-action system.

Wet pipe sprinkler systems generally have a longer life expectancy than dry pipe sprinkler systems since the oxygen corrosion is limited to the trapped air from the initial fill of the system. Wet pipe sprinkler systems regularly last 20-30 years before they begin seeing issues from corrosion. To significantly extend the life of a wet pipe sprinkler system, a property owner can add air vents to remove trapped gas from the system or use nitrogen gas to inert the system piping.


Taking this information into consideration can help property owners choose the right fire sprinkler system for their facility and properly maintain it. Reach out to our team of corrosion experts if you’re wondering how to get the most use out of your fire sprinkler system by effectively stopping corrosion.

Michael Taylor

Written by Michael Taylor

Project Engineer