The Portland Timbers and Allied Works Architecture met with the City of Portland's Design Commission Thursday to present their $50 million proposal for stadium expansion at Providence Park and request advice on the design.

While the expansion design was met with general support during the hour and a half meeting, the commission said it wanted more specific details surrounding the creation of a covered arcade and the expansion of the sidewalk on SW 18th Ave.

The commission addressed a number of aspects in the design throughout the meeting, but seemed most interested in ensuring that the new arcade would be aesthetically pleasing and desirable for pedestrians. The commission also asked the Timbers and Allied Works Architecture for more specific information about how street lamps and fixtures would exist along the arcade and how far the sidewalk could be extended with the existing MAX line on SW 18th Ave.

"I thought a lot of the comments on streetscape and how to enhance the quality of the arcade itself were really good," said Brad Cloepfil, founding principal at Allied Works Architecture. "I thought they were really thoughtful and intelligent comments ... They are asking for what is the real life of the place at the street level."

The Timbers and Allied Works Architecture will have at least one more meeting with the Design Commission as they continue to finalize the expansion design. They are expected to return to the commission within the next month or two with more specific design details based on the requests from Thursday's meeting.

"We'll have more details on the facade itself and the streetscape," Cloepfil said.

The meeting came a day after the Portland City Council unanimously voted to approve supporting the Timbers' proposed expansion plan, which would add approximately 4,000 new seats and four new levels to the east side of Providence Park. The plan would be privately financed by the Timbers, but the club would not have to pay a ticket tax on the new seats for the first 10 years following completion of the project.

Construction on the new project could begin as early as the 2017 offseason and conclude ahead of the 2019 season if the proposal is finalized by September. If construction does not start this year, it would be pushed back to the 2018 offseason with the goal of completing construction ahead of the 2020 season.

-- Jamie Goldberg | jgoldberg@oregonian.com

503-853-3761 | @jamiebgoldberg