Sprinkler systems for commercial buildings are mandatory. They're not required in new home construction but a NIST study says that, above a 100 percent reduction in civilian deaths, they make economic sense.

According to NIST, the cost in 2005 dollars for adding a multipurpose network sprinkler system to a house under construction was approximately $2,075 for a 3,338-square-foot colonial-style house, $1,895 for a 2,257-square-foot townhouse and $829 for a 1,171-square-foot ranch house.

However when a house fire occurs, the estimated benefits of a residential fire sprinkler system include a 100 percent reduction in civilian fatalities and a 57 percent reduction in civilian injuries, a 32 percent reduction of both direct property damage (property losses that would not be covered by insurance) and indirect property costs (fire-related expenses such as temporary shelter, missed work, extra food costs, legal expenses, transportation, emotional counseling and childcare). Houses with sprinklers, in addition to smoke alarms, also received an 8 percent reduction in homeowner insurance premiums, over houses only equipped with smoke alarms.

After subtracting installation costs and weighting the benefits by the odds that a house would catch on fire, NIST economists concluded that, depending on assumptions, the net gain from installing a sprinkler system (in 2005 dollars) would vary between $704 and $4,801 for the colonial-style house, between $884 and $4,981 for the townhouse, and between $1,950 and $6,048 for the ranch-style house, over the 30-year study period. In all cases examined, the researchers found that the data supported the finding that multipurpose network residential fire sprinkler systems are cost-effective.

NIST's Benefit-Cost Analysis of Residential Fire Sprinkler Systems report examined data from 2002 to 2005. It estimated the additional economic benefits from installation of a multipurpose network sprinkler system (the least costly wet-pipe system available) for three types of newly constructed single-family houses that are also equipped with smoke detectors.

The United States Fire Administration (USFA), part of the Department of Homeland Security (DHS), funded the research.

Benefit-Cost Analysis of Residential Fire Sprinkler Systems (NISTIR 7451), David T. Butry, M. Hayden Brown and Sieglinde K. Fuller