If they can afford it, Twin Cities area renters now have access to apartment buildings with the kinds of amenities and features typically found in high-end houses and luxury resorts: Spas for people and dogs, apps that control everything from lights to package delivery and indoor and outdoor gathering spaces with chefs kitchens, firepits and big-screen TVs.

With pandemic worries unlikely to subside anytime soon, developers are now trying to woo renters with a perk that can't be seen: fresh air.

Several Twin Cities apartment buildings are being built — and retrofit — with a range of features that aim to help ease concerns about the COVID-19 pandemic. From wider hallways to expensive high-tech ventilation systems, a handful of rental owners are incorporating health-focused features that can cost tens of thousands of dollars, but give them a competitive edge over other high-end apartment buildings.

"Air has always been this unseen commodity," said Patrick Crowe, a Twin Cities-area developer. "But we've become hyper aware of it since the pandemic."

Crowe had long planned to make the Quentin, a 79-unit apartment building that's under construction in St. Louis Park, a showcase for the latest sustainability and energy-efficiency features. Since the pandemic, he's doing even more.

The five-story building was designed to enable residents to live "net zero," meaning they won't consume more energy than is produced on site or purchased through solar and wind credits from Xcel Energy. Strategic placement of operable windows enable residents to take advantage of as much natural light as possible. The building will have supplemental smart LED lighting, smart thermostats and additional insulation to help withstand extreme temperatures.

Crowe said that since the onset of the pandemic, he has added other features. Common spaces were also adapted to facilitate social distancing, including wider corridors and indoor and outdoor areas that enable residents to gather safely. For $850 residents can upgrade to a catalytic air-cleaning system that kills bacteria and viruses and he has added energy-efficient elevators with an air-purification system that kills bacteria and viruses. He has also increased the size of those elevators to enable residents who are sharing a ride more space to keep their distance and to maximize air volume in elevators. He has also added stainless-steel interior surfaces to make them easier to clean.

And this week crews are installing a rooftop system that will continuously supply fresh air to the building. That's in contrast to more standard techniques that bring fresh air exchange into the units only when the individual heating and cooling systems are operating. And soon, crews will begin installing 85-kilowatt rooftop solar panels.

Crowe said the upgrades will add about 10% to the cost of the $22 million project, which includes eight income-restricted units for people who earn 50% of the area median income. Market-rate rents start at $1,460 for a studio unit.

Developing a "healthy" rental building stems from Crowe's interest in a building that's more energy efficient and sustainable than what's currently available for the market. And while he said the marketing potential of such features wasn't his primary motivation, he and other developers are constantly looking for ways to make their buildings stand out in an increasingly competitive market.

"People really want to know about the quality of their spaces they're living and working in," he said. "And now people are way more hypersensitive about it."

That includes renter Lauren Strahan, who said the focus on air quality in the building played a significant role in her decision to sign a lease in the building, which is currently preleasing and will open this summer.

"Since we are still in a pandemic I wanted to choose an apartment complex that provided outstanding air quality in order to continue to be as safe as possible," she said.

She said she was initially drawn to the building by its fitness facilities including the yoga studio, Peloton equipment and year-round spa area where she can relax after workouts.

"Initially I wasn't aware of the air quality being something that I should be concerned about," she said. "This year has really shined a light on the importance of a healthy living environment."

At the Viridium (Latin for "green") Apartments in the North Loop neighborhood in Minneapolis, Twin Cities-based Schafer Richardson lists "antimicrobial surfaces and materials" and an "air-cleaning ventilation system" among its amenities.

The building, which opens next month, is also pursuing LEED (Leadership in Energy and Environmental Design) certification from the U.S. Green Building Council. That includes meeting higher standards for indoor air quality, materials and sustainability.

Katie Anthony, director of development, said that in response to the pandemic, the company has also installed ionizers in Viridium's common areas, and in all other common areas in the company's portfolio.

The same is being done at most of the buildings that are owned and managed by Kelly Doran. At the Mill & Main Apartments across the Mississippi River from downtown Minneapolis, the company is finishing the installation of ozone-free ionizers in all common areas and are making them available for residents who pay an upcharge to have them installed directly into their apartment's heating and cooling systems.

"They're not cheap," Doran said. "But if a resident wants one, we add a little to the rent to help pay for it."

He said the company has also hired its own on-site cleaning staff rather than outsourcing it in an effort to do more regular cleaning, and he's bought electrostatic sprayers, which are used several times a week throughout each building in all common areas.

Pat Huelman, coordinator of the Cold Climate Housing Program at the University of Minnesota, said that with some exceptions the apartment industry hasn't embraced cutting-edge building science technologies that are more common in other sectors of the construction industry.

To date much of the focus has been on preventing the transmission of sound and smells between apartments. Now, more research is being done on preventing viruses and other contaminants being shared from one unit to the next.

"It wasn't one of their top priorities. It's a little more challenging and more expensive," Huelman said. "Getting them up quickly and at a very competitive price point with enough pizazz to catch eyeballs is what it's been about."

Jim Buchta • 612-673-7376