WESTPORT — The town officially has a new private museum and arts center with the Sunday opening of MoCA Westport, aka the Museum of Contemporary Art, at 19 Newtown Turnpike.

“Today is our public opening,” said Executive Director Amanda Innes, adding there had been previews for members and neighbors earlier this week.

The 1926 building, which was part Martha Stewart’s former studio, was over a year in renovation — part of a six-acre parcel that allows the rejuvenated organization to comfortably house exhibits and offering education classes and events.

“We have quadrupled our size, which was really the point,” Innes said, noting while the previous space on Riverside Avenue was beautiful, “It was almost like trying to do all that programming in a one-room schoolhouse.”

“Now we can run multiple programs in multiple rooms at the same time,” she said. The organization is 100 percent privately funded.

The opening corresponded with the exhibit of two renowned installations by artist Yayoi Kusama.

On display for the first time together anywhere in this part of the country are “Narcissus Garden” — an expansive room of bowling ball-size reflective steel orbs — and “Where the Lights in My Heart Go”— a walk-in multireflective cube spotted with seemingly infinite light.

Both pieces are on loan from Westporters Derek and Lauren Goodman.