Changing Trends in Rack Systems Demand a Closer Look at Sprinklers

Last month, we discussed building and fire codes you need to consider should you decide to expand your warehouse operations. Now, let’s consider sprinkler systems for the warehouse along with what you need to know before moving forward.

The National Fire Protection Association (NFPA) is the organization tasked with writing codes and standards for fire protection to minimize the risk of fires in all types of buildings, including warehouses. The code addressing rack systems and warehouses are found in NFPA 13. While NFPA 13 discusses the code for warehouses/rack systems, it does not make any recommendation on what type of sprinkler system to use. There are two main types of sprinkler systems: Early Suppression Fast Response (ESFR) and in-rack sprinklers (highly flammable liquids and aerosols require water/foam-based systems that are not covered here).

ESFR versus in-rack sprinklers

The current sprinkler system of choice is the ESFR sprinkler system. The ceiling-based system became popular over 30 years ago because it could knock down and prevent a fire quickly in facilities with a ceiling 30 feet or lower. ESFR systems improved over the years, allowing ceiling height requirements to reach up to 45-48 feet. The system releases a larger volume of water much faster than traditional sprinkler systems with the goal to suppress the fire.

In-rack sprinklers are another option available. This system works best in warehouses where the racking does not permit the free flow of water from ceiling sprinklers down to the fire. Typical reasons for this include the use of solid decking or other impediments to prevent water from reaching the fire source quickly.

Many warehouse owners prefer to use the ESFR system. The main reason is cost. An in-rack sprinkler system requires more sprinkler heads to cover the entire rack. Damage is another issue. Because pipes feeding the sprinklers are at ground level versus overhead with ESFR system, there is greater likelihood of damage. The pipes are hit by forklifts in the aisle and while handling pallets in the rack.

The tight demand for available warehouse space is causing owners to look at higher rack options. This also will require a different approach for sprinklers. As previously mentioned, ESFR can extinguish fires on ceilings 45’ (and in some instances up to 48’) as a standalone system. As racks heights increase, the need for in-rack sprinkler solutions grows.

Height demands put strain on water

Ceiling only ESFR sprinklers experience a decrease in efficiency as rack heights increase. According to one engineering firm, increasing rack height to 48’ will require a 140 percent increase in water demand. This, in turn, requires larger pipe sizes, the addition of a fire pump and possibly an on-site water storage system. All this adds to the price tag of a sprinkler system. Additionally, the packaging for many products now favors plastic over corrugated, which increases fire risk.

The trend toward taller racking is causing many to reconsider in-rack sprinkler systems. Newer in-rack systems offer better water dispersal (up to 60 gallons per minute, gpm) reducing the number of sprinkler heads needed to provide maximum coverage. These improvements also keep installation costs under control.

You need to know your options if you plan on building or expanding your warehouse. Make sure someone on your team understands NFPA 13 as it relates to racks. Engage professionals who know racking systems and sprinkler options, particularly if the expansion is higher than 45 feet.

Because expansions of racks and sprinklers need coordination, you may wonder if two separate companies need to install each. Many rack installers offer packages to combine rack and [in-rack] sprinkler installation, but you need to find this out before moving forward.

Rented warehouses

At this point, you may be thinking, “I only rent and the warehouse already has a sprinkler system,” so there is no need to worry. Your local fire department may think otherwise. Just because there is a sprinkler system in the warehouse you rent does not mean your product is protected from fire. The sprinkler system may not be rated to protect the types of products you’re storing or the protection may not be adequate. It is not uncommon for renters to pay additional costs and fines because they didn’t do their homework before agreeing to rent.

The bottom line

Know what the requirements for fire protection are before you make a decision to build, expand or rent warehouse space.