Construction is proceeding rapidly at a long-awaited transit-oriented-development next to the El Cerrito Del Norte BART station.

Work on the first phase of the Mayfair project, named for the grocery chain that once occupied the block, started Oct. 28 with the installation of the first modular units. Ten days later the assembly of modular units had reached its full height of six stories.

The modules for the 156-residential-unit portion of the project were assembled starting in June 2019 at Factory_OS at its 258,000-square-foot former U.S. Navy maintenance building 19 miles away at Mare Island in Vallejo.

Factory_OS is doing the construction for its partner, Holliday Development of Emeryville, on the market-rate portion of the Mayfair project.

Factory_OS, which opened two years ago, uses assembly line methods to do the majority of construction stages off-site (OS) in a controlled setting unaffected by weather, the fall of darkness or other factors that can plague outdoor construction.

The startup says construction can be done 40 percent faster and 20 percent cheaper than work done in the traditional way at a construction site.

Delivery and assembly of the modules will take about 25 working days in all and work to finish the site will take another six months, according to El Cerrito City Manager Karen Pinkos.

Along with the market rate residential portion, the first phase of the project will also have 9,000 square feet of commercial area that is now under construction and up for lease as one to four spaces.

The second phase of the project is a six-story building of 67 to 74 affordable apartments proposed by Bridge Housing for the northern end of the block.

“The number and level of affordability will be determined by the funding source,” Pinkos said in a city manager’s report. “Shared public open space will connect the two developments and be open to the public during daylight hours.”

The city is working with Bridge Housing on funding sources for the second phase, with a goal of breaking ground in summer of 2022.

Public art planned for the site is a metal sculpture that moves as BART trains pass the property.