ANN ARBOR, MI -- A community bath house is coming to downtown Ann Arbor.

The City Council approved plans this week for the 12,398-square-foot, two-story Sun Baths to be built at 319 N. Main St., just north of Miller Avenue in the Kerrytown area.

The estimated cost of construction is $3.5 million.

So, what's a bath house?

If you ask Peter Woolf, owner and operator of Sun Baths, it's somewhere between a spa and a water park.

"It's a different kind of space in this way," he said. "The intent of it is essentially a quiet space, a meditative space, a space for relaxation, a space with hot tubs, a space with saunas, a space with places to relax, a restorative community-centered place, so that's our intent with the space overall."

If that sounds like a new concept, that's because there's nothing quite like it anywhere around here, Woolf said.

So, why a bath house?

"It's essentially a place to build community," said Woolf, who has lived in Ann Arbor for several years -- as a graduate student, engineering professor and manager of a number of tech startups.

"We increasingly live in a disconnected community where people are more and more isolated by their devices, their cars," he said. "They live in their little bubbles, and they're people who historically have been drawn to places of warmth, water and plants. This is what we're trying to achieve here is to create a place where people can come together and people can, in quiet and relative less distraction, actually experience what it's like to act as a community."

Woolf said operating a bath house is energy and water intensive, so the team behind Sun Baths is working to make it as green as possible.

The building is designed to harvest most of the rainwater that falls on the roof for reuse within the building.

It also is designed to be LEED Platinum and net-zero certified, with rooftop solar panels supplying all of the building's energy needs.

"We're incredibly water, incredibly energy efficient, unlike anything the world has seen in this way," Woolf said, noting those efficiencies translate to improvements to the company's bottom line to make it more economically viable.

"So, it's actually where doing well economically and doing well socially come together."

Woolf, who has a background in chemical engineering, said small technical improvements can yield tremendous improvements in performance.

The building will contain a mix of common bath and sauna areas, as well as smaller private bath spaces.

There will be a larger pool area that is the "main waters" area for bathers to rest and relax between other bath areas.

No onsite automobile parking is proposed, though plans indicate there will be bicycle parking.

Before the council unanimously approved the project Monday night, Council Member Sumi Kailasapathy, D-1st Ward, asked about the building's potential to be repurposed in case it doesn't succeed as a bath house.

Woolf responded by saying it could be reconfigured for office or restaurant use without too much trouble.

Council Member Chuck Warpehoski, D-5th Ward, said he's really excited about the environmental features built into the project and he hopes it paves the way for other property owners to make the best use of rain and sunlight.

"This building is truly one of the most extraordinary buildings that we've seen here in Ann Arbor," Ann Arbor resident Matt Grocoff, a consultant on the project, told members of the city's Planning Commission last month.

Aside from being a beautiful building, he said, it follows stringent environmental standards. He described it as a building of the future and noted there even would be an urban agriculture component with food grown on the property.

Ryan Stanton covers the city beat for The Ann Arbor News. Reach him at ryanstanton@mlive.com.