Fire sprinkler mandates will be part of the 2009 International Residential Code and will be required in all one- and two-family homes and townhouses that build to the code as of Jan. 1, 2011.

The sudden — and controversial — arrival on Saturday of 900 fire officials eligible to vote at the International Code Council's final action hearings in Minneapolis swelled the number of sprinkler proponents and the measure was approved by a vote of 1,283 to 470 on Sunday morning.

In other business, voting members disapproved the so-called "30% Solution" from a coalition of insulation and window manufacturers that would have significantly revised the International Energy Conservation Code and also split votes among a number of wall bracing proposals.

About 1,200 voting devices were turned in immediately after the residential fire sprinkler mandate was approved; suggesting that most of the proponents left immediately after the vote was taken.

The residential fire sprinkler mandates will provide a sizable financial boon for the fire sprinkler manufacturing industry, which, like NAHB, helped provide funding for building officials to attend the hearings.

In 2005, when there were about 1.65 million new homes constructed at an average 2,340 square feet, sprinkler manufacturers would have reaped about $5.8 billion in revenue, based on average sprinkler costs of $1.50 per square foot, had the sprinkler requirement been in effect.

NAHB had identified several concerns over residential fire sprinkler systems — among them, questioning whether most home owners are prepared to perform the maintenance required to ensure that the sprinklers remain operational.

Builders also cited the potential for pipes installed in attics to freeze in colder climates and they said that the sprinklers can be discharged accidentally, with damaging results. In areas served by wells or where water is scarce, the availability of an adequate water supply is another possible problem.

NAHB pointed to several existing code requirements that have contributed to a significant decline in fire-related deaths and injuries over the past 30 years.

The most effective improvement has been the introduction of hard-wired interconnected smoke alarms, which the code requires to be installed in every bedroom and on every floor. National Fire Protection Association reports conclude that about 890 fatalities could be avoided each year if every home had at least one working smoke alarm.