[caption id="attachment_85543" align="alignnone" width="500"] Blu Homes opened its 250,000-square-foot factory on Mare Island in Vallejo in late 2011.[/caption]

VALLEJO -- Blu Homes, manufacturer of prefabricated, fold-out homes, on Tuesday said it plans move its corporate headquarters in San Francisco to its existing manufacturing facility on Vallejo's Mare Island.

The announcement follows recent news that the company would add more than 100,000 square feet of office and storage space to its existing 275,000-square-foot plant, creating a single hub for engineering, design and other operations at the rapidly growing company.

"Two years ago, Blu opened this facility with 20 factory employees," said Bill Haney, chief executive, in an announcement. "With this move, we now have more than 260 craftspeople, engineers, architects, product development, project management and business professionals here."

Blu Homes plans to construct an office mezzanine in its existing plant, and has leased other space from Lennar Mare Island to house design, marketing, engineering, finance and administration.

The company will continue to have an office of around 15 employees in Waltham, Mass., primarily focused on business development on the East Coast, according to spokeswoman Dana Smith. The number of employees moving from the office in San Francisco was not immediately available, but all employees at that location are planning to move to Vallejo following the closure in April, she said.

Blu Homes previously announced that it would close its 38-person, design-focused office in Ann Arbor, Mich. Fourteen of those employees had accepted positions in Vallejo as of December.

The company on Monday also broke ground near its factory on what it's calling Blu Design Center. It is intended to showcase the concept for the for consumers in a structure based on its "Breezehouse" design.

The six-and-a-half-year-old company opened its Vallejo facility in late 2011. The homes are partially completed on the assembly line, walls folded in sections along proprietary hinges for delivery to the job site and moved into place by crane. That approach can shave weeks off of on-site construction time and allows for a range of design and energy-efficiency features.

Blu Homes had $60 million in booked sales in 2013, after $40 million in 2012, according to the company. The company raised $65 million in a funding round June and has raised a total of $134 million.