I can see where the County's position is coming from. As technology has advanced, the standards that are expected of a house to be considered suitable for human habitation have advanced, as well, to keep up with technology. Most of us take it as a given that be suitable for human habitation at this time, a house should have indoor plumbing with running water and flush toilets, electrical service and other basic utilities, and meet certain modern construction standards. For the most part, I think most of us would agree that it is reasonable for local authorities to enforce such standards with regard to habitability.
The Amish present an odd challenge. For religious reasons that surely seem reasonable to them, they eschew the use of many modern technologies, including some that are essential to modern housing standards. It seems to me that as long as they don't cause harm to others, or undue harm or danger to themselves, they should be allowed to live in homes that comply with their religious standards. This seems like a case where, any imposition on the part of government that is in conflict with the Amish's religious practices should be held to the
“strict scrutiny” standard.