At first glance, the new Douglas Dayton YMCA in Gaviidae Common seems to contain a bit too much open air and not enough big spans of floor space for working out.

The facility, which opens to members Friday, occupies 105,000 square feet of space on five floors of the former downtown retail center at 651 Nicollet Mall in Minneapolis. Rising through the middle of it is Gaviidae’s signature atrium, largely cutting the facility in half.

Gaviidae’s design – never intended for a health club – forced the YMCA of the Greater Twin Cities and HGA Architects to carefully carve out space for a basketball gym, a swimming pool and group fitness rooms. It was a small price to pay, said Greg Waibel, the Twin Cities YMCA’s chief operating officer, because the views of workout facilities through the multi-story atrium are the Y’s best advertising.

“It was one of the things that really attracted us,” he said Thursday at an open house.

The facility has been under construction for 580 days and will see the last workers leave the site the first week in February, Waibel said. The YMCA, which is moving from its longtime location at LaSalle Plaza at 30 Ninth St. S., spent $30 million to renovate a building once best known for its Neiman Marcus and Saks Fifth Avenue stores.

Those stores and others have since closed, leaving much of Gaviidae Common vacant. The YMCA announced in February 2016 that it would move, and later won support for the project from the city, which approved a $15 million bond issuance to help finance the project.

Mayor Jacob Frey, who served on the City Council at that time, said that the YMCA’s plans got his attention.

“This project, when it was first introduced to me at the city, I was so intrigued,” he said at the open house.

Golden Valley-based RJM Construction is still on site to finish the YMCA’s swimming pool and outdoor rooftop workout area. The project involved 41 subcontractors and as many as 150 construction workers on the job daily, said RJM spokeswoman Mindy Bohumolski.

Glen Gunderson, president and CEO of YMCA of the Greater Twin Cities, said during Thursday’s event that the YMCA is “innovative.” Along with the health club, it features a leadership training center, business incubator space, and office space for the organization’s corporate staff.

But it is the health club that has all the shiny, fancy bits. It features a stationary cycling studio with an interactive display showing how everyone in the room is performing. One of the group fitness studios comes with a light show worthy of a nightclub, and members can sign up to use one of two hydrotherapy massage beds after a hard workout on cardio or strength training equipment. The YMCA even has demonstration models of virtual reality fitness machines.

All the workout equipment and space are spread across the third, fourth and fifth floors of Gaviidae Common. The YMCA is also leasing 3,400 square feet of space on the first two floors of the building.

The facility’s splashiest accessory — a 25-yard long, four-lane swimming pool on the fourth floor – was also one of the most challenging. To reduce the pool’s weight and stress on a building designed for retail use, HGA Architects ordered a pool basin fabricated from one-eighth-inch thick stainless steel. Typically, such a pool would have an 8-inch concrete basin, according to the YMCA staff.

Although it might seem like a lot of expense and trouble just to move a few blocks across town, Waibel said the YMCA made the move, in part, to increase the health club’s connection to skyway traffic and the growing residential population. The site currently sees about 29,000 people using skyways at Gaviidae, according to numbers provided by the YMCA. Its LaSalle Plaza location sees fewer than 9,000.

The YMCA also estimates that 36,000 people work within two blocks of the new facility, triple the number in the same proximity to the LaSalle YMCA. More than 1,800 people also live within two blocks of Gaviidae, up from 380 near LaSalle.

The YMCA expects the new location will help increase membership from the current 3,100 to 5,000 by the end of 2018, Waibel said.

The YMCA is moving all of its downtown operations to Gaviidae Common. It will sell the 118,000-square-foot facility at LaSalle Plaza and the 28,000-square-foot headquarters building at 2125 Hennepin Ave. E. The Minneapolis office of CBRE is marketing the LaSalle property as office space and the YMCA is in talks with a potential buyer, Waibel said. The asking price for the property is $10.5 million, according to CoStar.

The YMCA purchased the Gaviidae space in 2016 for $9.9 million. It later sold 51,000 square feet of that space to United Properties for its headquarters for $2.35 million, said YMCA spokeswoman Joan Schimml.

The YMCA has raised $10 million in donations to pay for the new location. It will also use proceeds from selling its property at LaSalle Plaza and on Hennepin Avenue East to pay for the project.

The new location was named after Douglas Dayton, the biggest donor to the YMCA of the Greater Twin Cities, according to the YMCA. He also was the first president of Target Corp., when it was owned by the Dayton’s department store family.