Published on October 1, 2016.


The 2015 International Residential Code (IRC) is the third edition of the code that requires the installation of fire sprinklers in all new one- and two-family homes. California, Maryland, and the District of Columbia, as well as hundreds of other jurisdictions across the United States, have adopted the IRC sprinkler requirements. Whether or not their state or community currently requires sprinklers, here’s what builders need to know about this life-saving technology.

1. Residential Requirements

Installation is governed by NFPA 13D, Installation of Sprinkler Systems in One- and Two-Family Dwellings and Manufactured Homes. Fire sprinklers are designed for life safety, meaning installation is required only in living areas. The standard requires at least 10 minutes of sprinkler water flow on the fire.

2. Water Supply

Home fire sprinklers are commonly supplied via the household water main. If water pressure is low, a tank supplies water to the sprinklers. Both water supply methods achieve the water flow requirement of NFPA 13D.

3. Installation

Sprinkler piping is installed behind the walls and ceiling, just like plumbing. Modern sprinkler piping can be made of chloro-polyvinyl chloride (CPVC) or cross-linked polyethylene (PEX), both cost-effective, lightweight materials. In unfinished basements and multi-purpose systems, where the same pipe is used for domestic water supply and fire sprinklers, copper pipe is often used. Fire sprinklers are fitted along the piping according to a unique hydraulic design for the structure.

4. Types of Sprinklers

Home fire sprinklers are small and inconspicuous. There are recessed and pendent designs. Concealed sprinklers are also available, and many manufacturers offer custom colors.

5. Heat-Activation

All home fire sprinklers operate in response to the high temperature of a fire, usually 135°F to 165°F. Smoke or a smoke alarm signal cannot operate a fire sprinkler. Each sprinkler reacts to nearby high heat individually. Unlike movie special effects, fire sprinklers do not flow water simultaneously unless multiple sprinklers are exposed to their activation temperature.

6. How Sprinklers Work

In the event of a fire, the sprinkler nearest the fire will operate automatically while the fire is still small, controlling or extinguishing it, often before the fire department arrives. That fast response limits the spread of flames, heat, and poisonous smoke. In 90 percent of home fires, just one sprinkler is needed to control the fire.

7. Maintenance

NFPA 13D recommends little maintenance. Homeowners should periodically test the pump (if present) and visually verify that all valves are open and the storage tank is full (if present). The water flow device and monitoring service (if present) should also be tested periodically. Year-round, the homeowner should look at sprinklers and visible pipes to make sure nothing is blocking or hanging from them.

8. Cost

A national study shows that the cost of installing home fire sprinklers to the builder is $1.35 per sprinklered square foot for new construction.

9. Incentives

Many municipalities offer homebuilders incentives to install sprinklers, such as allowing more residential units, longer dead ends and reduced street width, tee turnarounds, increased hydrant spacing, and many other benefits that save money and increase builder profits.

10. Working with Contractors

The Home Fire Sprinkler Coalition recommends selecting an experienced residential contractor knowledgeable and trained in NFPA 13D systems.