“There’s an intangible side to this that’s horrible,” he continued.

Insurers have generally refused to pay for repairs, strictly defining the coverage of collapse by inserting the word “abrupt” in policy language. Repairing the homes requires replacing the entire foundation at costs that typically range from $100,000 to over $200,000. So far, 223 residents have filed formal complaints about crumbling foundations with the department, but officials believe many homeowners may be reluctant to contact the state, fearing problems from their banks and insurers.

Because the affected swath of the state is home mostly to working- and middle-class families, many face financial ruin since their homes represent the biggest part of their nest egg. Ms. Miller, whose insurance company has provided no financial assistance, rented a nearby condominium after she was told that her family was no longer safe in their home.

But Ms. Miller said she could not pay both the monthly rent and the mortgage. Paying out of pocket to replace her home’s foundation, she said, is well beyond reach. “I don’t know too many people that have $170,000 in their wallet,” she said. “And that’s what it’s going to cost to fix my home.”

Mr. Neal, the structural engineer, has inspected hundreds of houses. In nearly all, he found concrete walls with distinctive crack patterns that resemble a road map with lines and fissures snaking in all directions — much different than the vertical cracks typically seen in foundations as they settle.

After hearing from tearful, angry residents at packed public meetings, state officials stepped in. In October, the state’s Insurance Department warned insurers not to cancel policies because of a foundation’s condition. Since insurers are denying claims, that warning may not help with the concrete problem, officials say, but it should at least prevent homeowners from losing insurance protection all together.

Last month, the Connecticut General Assembly passed a bill that would, among other things, allow homeowners with failing foundations to request a reassessment of their property values and require contractors to record the supplier of concrete for residential foundations. Gov. Dannel P. Malloy, a Democrat, signed the bill into law last week.