Montville — Residents of a 16-unit apartment complex could be let back into their homes temporarily as early as today following a partial roof collapse on Monday that building officials say was likely caused by the buildup of snow.

Nearly two dozen residents were evacuated late Monday night after the roof of the Mount View apartment complex at 1591 Route 32 started to sag and pieces of wooden beams broke through tenants’ ceilings.

At about 11:45 p.m. Monday, tenants started to call 911 reporting a loud “boom.”

Building Official Vernon Vesey ordered the owner to hire a structural engineer and on Tuesday afternoon the engineer reported significant concerns with the structural integrity of the roof.

“The roof is in danger of collapse. It’s not habitable right now,” Vesey said. “Even allowing people to remove their furniture could cause a potential, unsafe shift.”

Town police were stationed at the entrance to the complex to stop anyone from going in.

The issue appears to have been caused in part by the weight of snow, and perhaps some outdated construction methods. Vesey said the roof rafters are sagging and slipping outward off the walls, breaking supports that connect the rafters to the ceiling joists. Cracks can be seen in the fascia board along the roof line.

Vesey said it looks as though the entire roof will eventually have to be replaced.

The owner is expected to hire contractors who will use lifts to first clean the snow off the roof and then shore up the roof supports from the outside of the building. Residents at that time will temporarily be allowed back in to retrieve personal belongings and any pets left inside.

Land records show that the building, which was built in 1970, was purchased in 2004 by Mount View Realty, care of Landmark Alliance LLC, of Monsey, N.Y.

A neighboring building located on the same property has not displayed any signs of similar issues, but Vesey said he suggested the engineer also take a look at it.

Vesey said he’s been in contact with the owner, Sol Grossman. Grossman could not immediately be reached for comment.

Building records show a smattering of violations through the years because of issues at both apartment complexes, though Vesey said none involved structural issues with the roof. A portion of the building in question was re-shingled within the past two years because of leaks, Vesey said.

Tenants were briefly taken by a bus donated by Mohegan Sun Monday night to the Mohegan Fire Department. The American Red Cross did assist but Fire Marshal Ray Occhialini said the landlord paid for rooms at the Red Roof Inn in New London for tenants who had no place else to go.

About 20 people were in the building at the time of the evacuation, Occhialini said.

One tenant, who did not want to identify himself, went back to the building Tuesday morning to retrieve two cats from a first-floor apartment. He said he lived on the second floor but was moved to a different apartment on the first floor because the roof leaked.

“I heard a loud ‘boom’ and the apartment shook,” he said. “I came back to get my pets because I don’t know when I will be allowed back.”

Another resident was able to retrieve 13 cats from an apartment Tuesday before the building was closed off, Vesey said.

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