June 3, 2021

Howard S. Wright to build Mercer Mega Block towers

Image by NBBJ [enlarge] [gallery]

This view looks west up Mercer at the two buildings, with Ninth in the lower foreground.

Alexandria Real Estate Equities is planning two 13-story lab and office towers on the roughly 3-acre Mercer Mega Block in South Lake Union, which it has agreed to buy from the city of Seattle. The proposal, by NBBJ, has its second design review on June 16. That presentation will be virtual. About 865,000 square feet of office/lab space is planned for what Alexandria simply now calls the Mercer Blocks.

The general contractor for the project is now listed as Howard S. Wright (a Balfour Beatty company). The team also includes Westlake Consulting, construction manager; KPFF, civil and structural engineer; GGN, landscape architect; Prime Coffman, electoral; Lerch Bates, elevators; O'Brien & Co., sustainability; Hart Crowser, geotechnical; EA Engineering, SEPA consultant; Glumac, mechanical and plumbing; and Bush, Roed & Hitchings, surveyor.

The west and east towers are addressed, respectively, at 714 and 816 Mercer St. The west tower will have about 485,598 square feet. It's now dubbed “Labhouse.” The smaller east tower, dubbed “Clerestory,” will total about 379,126 square feet.

They'll be separated by a restored Eighth Avenue North, which will be a 16,750-square-foot pedestrian corridor and public plaza — not a street or woonerf. Both buildings will also have V-shaped columns, or stilts, on certain corners that lift some of their rotated mass above the street-level retail and amenity space.

NBBJ writes of the pair, “Mercer East and Mercer West have different design concepts. Each building's massing and facade responds to its context in a different way: Mercer West through a more vertical, folded expression; and Mercer East through a horizontal volumetric design. Each building maintains a unique character through distinct and responsive variances.”

The west tower will feature a dramatic open stair on its pointy prow — aimed west up Mercer. It will also be home to a recreation center and sport court for the city, to be rent-free for 40 years. That space, including a childcare center, will total about 30,000 square feet. It's one of the amenities Alexandria negotiated in the $143.5 million sales agreement. That deal has yet to close. The Mandatory Housing Affordability payment is estimated at about $9.8 million.

Alexandria plans to meet green certification requirements for LEED Gold, WELL-Ready and Fitwell. That will include measures like water recycling, energy efficiency, possible solar panels and the west tower's green roof and decks — which could total about 11,000 square. The east building may also have a small west-facing rooftop terrace with about 1,524 square feet.

Four levels of shared underground parking will have about 618 stalls, to be accessed from Roy Street. Tenant bike parking, with 394 stalls, would also be accessed from Roy, which has a bike lane. Showers are also planned for bike commuters. There would also be 97 short-terms bike stalls for other users.

Retail in the east building could total around 3,000 square feet. Most of the ground floor is indicated as lobby and amenity space, with flexible uses. A food hall had one been contemplated, but isn't now mentioned.

The slightly irregular floor plates in both buildings look to run from about 24,000 to 35,00 square feet. Both buildings will be about 175 feet high. Alexandria hasn't named a broker, though Newmark is representing the space in its nearby projects.

Those include the office towers planned at 601 and 701 Dexter Ave. N., which are not technically part of the Mercer Mega Block. (Alexandria acquired them separately.) The 701 Dexter project appears closest to starting, with the existing old building vacant and nearing demolition. ZGF Architects designed the new replacement, which Lease Crutcher Lewis will build. A permit application has been filed to use the west end of the main Mercer Mega Block for 701 Dexter's construction staging.

Also on the west side of Dexter is a planned 18-story, 394-unit apartment building at 615 Dexter. That's part of the pending Mercer Mega Block deal, too.