NORTH ADAMS — Work on a new airport administration building is expected to begin in the coming weeks.

The city is expected to select a $3.6 million bid from D.A. Sullivan & Sons to move a former doctor's building on State Road and renovate it into an administration building, with amenities that include a new restaurant, public restrooms and offices.

The lowest bid to renovate the building vastly exceeded the initial $2.1 million estimates; however, the bid still offers a substantial savings over what was initially envisioned for a new $4 million building.

"It is what it is. It's a little bit of an unknown; we're talking about moving a building," said city Administrative Officer Michael Canales.

How the city will pay an obligatory 5 percent of the project remains to be seen.

In 2016, the city announced it had won a $4 million grant through the Massachusetts Department of Transportation for the construction of a new airport administration building, coupled with a $200,000 city match.

But in the months afterward, the city formulated a plan to instead construct a new space within the vacant former Northern Berkshire Family Practice building, which already sits on city-owned land in front of the airport.

The belief was that, not only would building re-use cut costs, it also would better fit the aesthetic of the airport.

The building itself was donated to the city by Berkshire Health Systems, which acquired it through the bankruptcy of the former Northern Berkshire Healthcare in 2014.

To facilitate the plan, the building first has to be moved about 580 feet south along Bud Dougherty Drive, commonly called Airport Road.

Because most of the construction is slated to be done inside, work should be able to continue through the winter. The administrative building still is expected to open in spring 2019.

Harry Patten, owner of airport business Turboprop East, had pledged up to $200,000 when the grant was first announced to cover the city's matching share — which, under the terms of the grant, is 5 percent. In exchange for his pledge, the city agreed to give Patten naming rights to the building.

But in a letter to the mayor this summer, Patten withdrew his pledge, as the Airport Commission became mired in controversy regarding a lease to convicted felon Alex Kelly, owner of a Bennington, Vt.-based skydiving and flight instruction businesses.

Mayor Thomas Bernard met with this summer with Patten, who remained committed to withdrawing the pledge — but also that he would keep an eye on airport operations.

"I don't know that the door has fully closed, [but] I don't know that he has changed his mind," Bernard said.

Patten could not be reached for comment Wednesday.

Bernard said the city is "still looking at options" for funding if Patten remains committed to withdrawing his pledge.

"We're committed to the project, so we'll have to look at what we can do to fund it," Bernard said.

Adam Shanks can be reached at ashanks@berkshireeagle.com, at @EagleAdamShanks on Twitter, or 413-629-4517.