A proposal to double the capacity of the boutique Hob Knob Hotel caused some nobs to knock at the Martha’s Vineyard Commission Thursday, as neighbors voiced concerns about traffic and the appropriateness of the expansion in the Edgartown historic district.

The inn — a luxury, 17-room bed and breakfast nestled on Upper Main street — was formerly the Governor Bradford Inn before undergoing extensive renovations and becoming the Hob Knob Hotel in the early 1990s. The property changed hands in 2015 when owner Maggie White sold it to VIC Partners, a California-based LLC. Diane Carr is the general manager on the premises.

The proposed expansion was referred to the commission as a development of regional impact (DRI) by the Edgartown zoning board of appeals and includes an addition to the existing property at 128 Main Street and an expansion across Tilton Way to the site of the Tomassian Law Office. The hotel has not yet officially purchased the law office, according to land records, but attorney Sean Murphy confirmed on Friday that it is under agreement.

Rooms would increase from 17 to 35, according to a staff report by the commission, with the addition of a backyard pool, expansion of the hotel spa and a reorganization of parking on the site. The hotel also plans to tear down the current law office across the street and replace it with a slightly larger hotel structure and four units of workforce housing. Total building area on the site would increase by about 2,400 square feet.

The project needs a variety of approvals at the town level as well, including a signoff from the historic district commission.

Mr. Murphy represented the Hob Knob at the hearing on Thursday night. The builder is Patrick Ahearn.

Mr. Murphy billed the project as an important economic development for the town, saying that Edgartown had lost a total of 73 hotel rooms over the past decade. The addition would help Main street businesses frequented by guests, he said.

“It’s just a huge economic plus for everybody the more hotel rooms there are in the town,” Mr. Murphy said.

Mr. Ahearn described the aesthetic of the project, which he hoped would match the neoclassical style of the current buildings with minimal changes to their appearance.

“The Hob Knob is one of the important and significant inns as a gateway to downtown,” Mr. Ahearn said. ”It sets the town’s character in a very nice way.”

But neighbors who live in the historic village disagreed with the applicants on Thursday, arguing that the project as proposed was inappropriate in both style and scope.

Jane Chittick, who lives across the street from the hotel, said the architectural changes to the Tomassian building violated the tenets of Greek revival architecture and the historic district guidelines for building addition size and dormers.

“Our neighborhood in the historic district is being decimated,” Ms. Chittick said. “This is really a huge change. It’s obtrusive. And it doesn’t oblige by the historic guidelines at all.”

Other neighbors voiced concerns about parking and traffic at the site. Grant Greeley, who directly abuts the property on Tilton Way, said the new parking area proposed for 124 Main street would become “an interference” for residents. And Carol Wolff, who also lives in the neighborhood, felt similarly, saying traffic had increased dramatically.

“The traffic on Tilton Way has increased exponentially in the last five years,” Ms. Wolff said. “There is more activity in that small 18-foot way than you could possibly imagine.”

The commission has received nearly 15 letters about the project, with nine in favor and six opposed. Those in favor have touted the Hob Knob as an important and respectful business in town, and support the project’s aesthetics.

Commissioners continued the public hearing to Thursday, July 16.