The Builders Association of the Twin Cities has taken the state's new residential fire sprinkler mandate to the courts.

Saying the law is expensive and will price many buyers out of the market, the association is asking the Minnesota Court of Appeals to halt the program, which went into effect Saturday.

Under the new rules, all homes that are 4,500 square feet or larger (including basements) must have fire sprinkers, a requirement the Minnesota State Fire Chiefs Association applauds.

"It virtually guarantees that the occupants of that structure will not die in a structure fire as long as the fire sprinker system is operational and they have working smoke alarms," said Eden Prairie Fire Chief George Esbensen.

Though Esbensen said sprinklers represent a tiny fraction of the cost to build a home, Builders Association past president Shawn Nelson said the addition can increase the cost of a new house by $8,000 to $10,000.

"For every $1,000 we increase the price of a home, 2,000 families no longer qualify to build that home," Nelson said. "So we are really pricing a lot of people out of the market with mandates that are expensive and in many cases unncessary."

The Builders Association is also challenging new energy efficiency rules in the building code.