PORTLAND — A rooftop trellis helped sway Historic Preservation Board members April 17 when they reviewed the Fathom Cos.’ plans for a hotel at 1 Center St.

“I’m excited for this project; I think it is going to be a great addition to Commercial Street,” board member Robert O’Brien said before the vote to grant a certificate of appropriateness for the hotel construction.

The six-story, 135-room hotel, which would be operated by Hilton Hotels under its Canopy brand, is planned for the corner of Commercial and Center streets on what is now an Old Port parking lot.

The land sits within the Waterfront Historic District, giving the Historic Preservation Board a level of oversight along with the city Planning Board. The HPB vote came after it held three workshops.

The Planning Board held its first workshop on the site plan in February; a second workshop has not been announced.

At prior HPB workshops, city Historic Preservation Program Manager Deb Andrews said the top floor and roof design were problematic.

The design was out of context with surrounding buildings, lacking “a singularity of overall design expression that extends across the entire width of each building facade,” Andrews said in an April 11 memo.

In response, Fathom Project Director Marieke Thormann presented new plans that include the trellis “to create a corner condition to match the building perimeter of the floors below and improve consistency across the floor.”

Fathom Cos. Principal James Brady, who also built the Press Hotel on Congress Street, was more succinct.

“I actually think the whole trellis thing is pretty cool looking,” he said.

HPB members were uncertain how the trellis might affect light and shadows on the building and street, but remained supportive of the concept and the level of detail Fathom Cos. provided in presentations.

The hotel is in the Waterfront Historic District, but sits across the street from the Waterfront Central Zone, where hotels are a prohibited use.

If approved, it would be the second new hotel along the inland side of Commercial Street; developer Joe Dasco is building a 132-room hotel on the site of the former Rufus Deering Lumber Co. at 383 Commercial St.

The hotels also come about five years after the 130-room Courtyard by Marriott opened on Commercial Street, across the Maple Street intersection from the former lumberyard.

The Fathom Cos. hotel would also be subject to the new $3,800 per room fee passed by city councilors in January, money that would go to the city’s Housing Trust Fund.

David Harry can be reached at 780-9092 or dharry@theforecaster.net. Follow him on Twitter: @DavidHarry8.

Extension of a trellis on the roof of the hotel planned at Center and Commercial streets helped the project get the endorsement of Portland’s Historic Preservation Board April 17.

A portion of the parking lot at Commercial and Center streets could become a six-story, 135-room hotel operated by Hilton Hotels.