The Leader-Telegram reports that Judge Michael Schumacher's 11-page decision said the families are not burdened by the county's application process. The judge ordered the families to apply for the permits within 30 days or risk being removed from their residences.
State law requires new homes to include smoke and carbon monoxide detectors, but the Amish don't use electronic devices.
The case involves two Amish families from Fairchild who failed to obtain permits in 2012. They were issued violation notices at the beginning of last year.
Schumacher said there was little issue that the Amish have sincere religious beliefs that hinder them from following the requirement. But he also said that the application process doesn't include an "implicit promise" to follow the stipulations outlined in the permits.
None of the Amish involved in the case testified in the July trial. Schumacher alluded to his belief that it was significant.
"The burden is on the defendants, and they failed to meet that burden," Schumacher said. "The narrow issue is whether they applied and completed the application process."
Heather Wolske, an assistant county attorney, earlier said other groups might protest ordinances if it was determined that the Amish were burdened by the permits. She suggested that they pay forfeitures roughly between $15,000 and $300,000.
Eau Claire attorney Matt Krische, who represents the two Amish families, said in a report that the ruling is unfair.
"This requested punishment falls on the verge of ridiculous," Krische said. "The county's request is essentially asking the court to punish the defendants for their religious beliefs. All this would accomplish is driving away a peaceful community."
Krische said the families would be lying if they signed the applications without intent to abide by their rules. He said this would also cause them to violate their beliefs and be subject to church discipline.
"We are grateful for the support the Old Order Amish have received, both at the community level and the legislative level," Krische said.
The Amish families said they would likely appeal the ruling.