Take It Inside

Trends and Ideas for Natatorium Design


There's more than one thing designers and architects can agree on when discussing natatoriums, but the bottom line on all their common ground is this: It's a building and environment unlike any other.

Akin to constructing a rain forest exhibit in a zoo, an enclosed pool area has a climate that dictates everything from construction materials to heating and air conditioning systems to water filtering options to flooring surface choices to custom lighting and spectator space. All that has to be under the crucial umbrella of safety for users of the space and staff.

"We always stress that of all the spaces in your facility, this is the one you want to pay the most attention to," said Erik Kocher, principal and owner at Hastings & Chivetta Architects, St. Louis. "You really don't want to cut corners when you're talking about the quality of your pool environment, just because they can so quickly deteriorate because of the nature of the chemical environment, and it could become a long-term burden to the client. As architects, we want to make the building very efficient, but you also want to make it last."


Modern technology and innovation have given designers and architects new tools to pursue energy savings and flexibility in an era of revenue-generating recreation pool areas being added to traditional exercise and competition pools. Sometimes, as with natatoriums funded publicly, such as at universities and municipalities, efficient equipment and practices are mandatory. In general, they make good business sense, perhaps the best argument for any choices.

James Braam, vice president and director of sports and recreation and entertainment at HOK, Kansas City, said there's another aspect that should never be forgotten when planning, designing and building natatoriums:

"We really believe we have a chance to impact life-styles for everyone from youth to elderly or at a college campus. These buildings really should inspire. If there's ever a building type that should be both inspiring and sustainable, it's fitness and aquatic facilities. The idea of attracting people to these facilities so they want to linger and feel good. It's going a step beyond where we were 20, 30 years ago."

A new natatorium begins with usage goals and a budget. Will it be used only for competition? Only for recreation? A combination? Will there be a therapeutic water area, with the highest temperature of any of the three pool types? Can you afford the upfront expense of a movable floor, to change the depth of one pool to meet the needs of all users? Would you rather spend that money on separate pools? Will recreational spaces include moving water like lazy rivers or add-ons to still water like climbing walls, zip lines, inflatable obstacles and slides?


Scott Hester, president at Counsilman- Hunsaker, St. Louis, said efficiency, which every client wants, begins with the plan and design process. Most natatoriums are part of a larger building in a fitness, community or wellness campus.

"The natatorium space is one of if not the most expensive space in that facility, so being efficient is critical, and it starts with making sure the pool shape itself needs to conform with the building space and vice versa," said Hester. "If you've got a curvilinear or free-form shape to the pool the natatorium should have curved spaces itself. It's not just a block. Next, we want to eliminate as much deck as we can.

"We've been doing this now for 15 to 20 years. For instance, having part of a waterslide flume outside so you don't have all that winding and twisting eating up deck space for nothing other than a slide itself. So, while you might have a tower and the terminus within the building, a lot of the actual slide itself may be outside the building.


"Every inch needs to count inside that natatorium because, again, it's the most expensive space when you have it as part of a larger recreation facility. We're talking about the difference of, 'Do we want a 10-foot wide deck versus 8-foot wide?' There's a lot of dollars behind that decision."

Hester said the reason natatoriums are so pricey begins with their volume of space and continues with the mechanical systems necessary to control and monitor air and water quality, as well as the specialized materials that resist corrosion.

"Generally, it's a multi-story space, and the building conditioning is very significant in the cost to construct as well as to operate the facility," he said. "You've got a swimming pool, you've got expensive building conditioning equipment like dehumidification units, HVAC and building materials that are durable. A lot of times, more durable is more expensive."

Mark Bodien, partner at Moody Nolan Inc., Columbus, Ohio, says even the smallest and simplest natatorium is at least a seven-figure proposition.


"When people say we want a pool, that could go anywhere from $3 million to $25 to $30 million just by saying I want a pool," Bodien explained.

He said a hypothetical client who says money is no object would have separate natatoriums for separate uses, with a glass wall between. The recreational pool would boast lazy rivers, climbing walls, mood lighting, audio/visual capabilities for movie nights; top-of-the-line mechanical systems and durable building materials are assumed.

"The lazy river is sold not just as a fun element for kids, but for aerobic walks against the water," said Bodien.

Kocher added that the recreational space has many more options these days, as fun has become more of a focus for natatorium operators.

"It's almost a laundry list of the things you would like to offer your clientele, whether a municipality or college," he said. "Zero entry, bubble benches, vortexes, zero edge designs, rock climbing walls, zip lines, artificial palm trees, faux rocks and formations, grottos. When it's more about fun and not just a square body of water for competition, there's a lot of things you can do."


Bodien said the exercise and competition natatorium in the money-no-object facility would also be serious about its mission.

"The true extreme is the full 50-meter pool with bulkheads and dive towers," he said.

Braam said his firm has been working with major universities' swimming and diving teams on dry land training, deckside. Because of the gymnastic quality of especially the divers' efforts, practicing twists and turns and flips before climbing a ladder is helpful.

To top off the decadence, the ostentatious natatorium would have separate warm bodies of water for therapy, as well as whirlpools and hot tubs.

Bodien said the latter amenities also are part of recreational natatoriums, especially at university recreation centers. The trend of the past decade—to construct resort-type pool areas as differentiators for student recruitment—makes those spaces important social centers. It's considered a third use for a natatorium, and its clientele is mostly college-age people, as opposed to a municipal facility's age range from babies to the elderly.


No matter the age of the natatorium users, they need to see. Bodien said to him the largest technological leap for architects and designers is the advent of LED lighting. Not only is it energy-efficient, it is flexible, he said. From overhead lighting to underwater lighting, "the amount of control you have and the amount of energy savings is incredible," Bodien said.

"It's particularly important in a natatorium because these LED elements will last for years and years," he said. "Not only is it more energy-efficient, it allows colors, it allows mood lighting, it allows us to change the feel of a natatorium in an instant, to become a social space that is more than just turning half the lights on and half the lights off.

"We're just starting to exploit that the last two years. Facilities people are becoming comfortable enough that they're not guinea pigs. All our natatoriums, particularly leisure ones, take advantage as much as they can."



Braam said one of the major innovations for air quality is the rise of garage style glass doors that can help circulate a high volume of air. They might seem decadent, but the importance of air quality is paramount, he said.

"With one fell swoop we can get an entire volume of air change out of that," he said. "A complete refresh of air quality."

Hester said maintaining the atmosphere is not just for the people inside the pool area, but the equipment and surfaces as well.

"We want to maintain a good level of humidity, but we don't want humidity levels to be excessive," said Hester. "We want to bring in a sufficient amount of fresh air while also being sensitive to efficiency. If you did nothing but bring in 100 percent complete outside air, that's not a very efficient building.

"Moving the air, having good humidity levels, making sure that you're having a good stratification where you supply and return air. We would like to exhaust some air out of the building closer to the deck, right above the water level so if you're pulling air low you want to supply air high."

Bodien said the mix of moist air and chemicals is no joke, so climate control and proper materials can keep an operator from renovations longer.

"Stainless steel, there's really no such thing," he said. "Stainless does not mean stain-free. Humidity and the chemicals in the environment can attack. Technology hasn't changed a heck of a lot. It's been more trying to use less chemicals in the water and make the air healthier. To make the environment less corrosive. It's not a problem that magically goes away."

Kocher's firm has been bidding on a job that would require a tear-down and rebuild. Natatoriums built in the 1960s and 1970s are nearing or at the end of their life cycle; new builds will benefit from advancements in construction materials and surfaces designed to thrive in natatoriums.


"We're always very interested in how you develop building skin so you literally have a vapor-proof, waterproof skin and roof, including walls, roof and windows so you don't have any water migration because that's a common problem with older pools," he said. "There are some water shields that are being made better. As architects, you want to make the building very efficient, but you also want to make it last."

There is another consideration when planning, designing, funding and building: sustainability. LEED certification from the U.S. Green Building Council (USGBC)—the amassing of points by using energy efficient materials and practices—has been a goal of many who have built public use buildings in the past two decades. Whether the chase for LEED status is a cynical marketing ploy to boost company image, the result is the same; energy and cost savings as well as less stress on the environment.


Hester said some clients want the LEED materials and practices but don't want to register for the status, as it is an extra expense and paperwork.

"It's a given that everyone is designing with (LEED) in perspective now, whether or not a new project," Hester said. "Just because the owner does not want to achieve certification, that doesn't mean we're not following LEED design."

Bodien agreed. Sustainability simply makes sense, regardless of certification.

"Architects are almost all being sustainable or practicing being that way," he said. "Do you want to spend the extra money to get that piece of paper? Most projects have a target that is decided by the client early on. Others, particularly private colleges, aren't as interested in the piece of paper.

"They'll want us to go through the process of demonstrating and making sustainable choices, particularly where it saves them money and they can document it, but they don't have us register the project and get that piece of paper because there is a cost to it in terms of record keeping and getting the USGBC (to review)."