Whether you fantasize about having a swimming pool to play rousing games of Marco Polo with the kids or to emcee elegant poolside gatherings with guests in sarongs sipping margaritas, chances are you’ll need some accessories for the pool and the festivities.

Swimming pools tend to accumulate items such as volleyball nets, rafts and lounge chairs with cushions. Swimmers have damp bathing suits and wet towels, and they require thirst-quenching drinks and energy-boosting food. A well-designed pool house provides a practical space for showers and storage as well as a place to entertain friends and family.

A pool house can become a mini-vacation home right in your back yard, as it has for Kimberly and Scott Parks, homeowners in Great Falls, Va.

“Before we built the pool and pool house, we hardly used our back yard,” says Kimberly Parks. “There was a lawn and a garden there, but we tended to use our front yard more. Now we have a pavilion with a lounge area, a dining area, a kitchen and a bar, all wired so we can listen to music inside and outside.”

The Parks’s pool house — designed by Rill Architects, with a landscape design by Jay Graham of Graham Landscape Architects — started as a simple pavilion with screens to shelter Scott Parks when he grills. Over time, the plan morphed into a glass-enclosed pool house that the family uses year-round. The sliding glass doors on three sides are stackable so the pavilion can be almost entirely open.

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“It feels like we’re outside even when they are closed and we have the heat on in the winter,” Scott says. “We revisited our original design when we realized that we had all this semi-enclosed space but weren’t going to use it fully. For not that much more money, we have an entertaining place that we can use more often.”

A pool house can cost $25,000 for an open-air gazebo without a bathroom or kitchen. It can cost $500,000 or more for an elaborate structure with guest quarters. Pool houses average about $100,000, says George Myers, president of GTM Architects in Bethesda. He says the price rises depending on how far away it is from the main house because most people run the utilities from the main house. Installing heat and air conditioning also increases the cost. Jim Rill, principal of Rill Architects in Bethesda, estimates that a pool house with plumbing, electricity, a wine refrigerator, a TV, heat and air conditioning generally costs about $200,000.

“It’s typical to have a changing room, a full bath, a refrigerator or bar to keep drinks cold, a kitchenette and to have some storage for towels and pool equipment,” Myers says. “Some people also add guest space over the pool house, although some jurisdictions have rules about how often a detached building on your property can be occupied.”

Rill says about half of the pool houses he builds include indoor-outdoor living space for entertaining, and the other half are smaller and include a simple bar or kitchenette, a bathroom and changing room, and a laundry room.

“It’s important to include storage space for the outdoor cushions, towels and pool equipment so no one has to go back and forth to the main house,” Rill says.

The Parkses spent about $200,000 to $250,000 on their pool house. In addition to space for entertaining, the structure includes a large full bathroom with a shower and cubbies where guests can leave their clothes when they change into a bathing suit, a laundry and storage room, and an outdoor shower.

Myers says most homeowners also want a fireplace or fire pit inside or outside the pool house if their space and budget can accommodate one.

“During the design process, it’s essential to ask a lot of questions about how the homeowners plan to use the space,” says Fernando D’Tapia, design and creative director of Terranova Dreamscapes in Washington. “We can design a place that’s open-air on the sides or enclosed for year-round use with a game room and great room. It all depends on what people need.”

Lisa and Lacy Rice, homeowners in Chevy Chase, Md., who have a pool house designed by GTM Architects, opted to include a kitchen that has an island with bar stools and a refrigerator with plenty of freezer space for ice pops for their 12-year-old daughter and her friends.

“It was a big decision whether to include a TV or not, but we decided to add one so the kids can watch sports,” Lisa says. “They also listen to music through the TV.”

The Rices’ pool house has two connected pavilions, one with a changing room, benches, cubbies and a full bathroom with a shower. The other pavilion has a dryer for towels and storage space for pool equipment. They also have an outdoor shower. The pool house cost about $100,000.

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“Families need to think about how they will use the pool house at different phases,” says Don Nesmith, president of Land & Water Design in Haymarket, Va. “Most people want the pool house closer to the main house, especially if they have small children, but one family in Clifton had teenagers and wanted the pool house to be a place where their teens could hang out with their friends at home without worrying about noise. We placed that one a little farther from the main house.”

A pool house Rill designed in Potomac is far enough from the main house that a kitchen was required for entertaining family and friends.

“We put sliding barn doors on the outdoor kitchen to close it off when it’s not in use,” Rill says. “The really cool thing we did with this house is that we had the bathroom sink custom-made out of wood found on the property and put saloon doors on the shower.”

“Most people want their pool house to relate to both the pool and their main house so they all function together to define the space,” Rill says. “Designing a pool house gives you an opportunity to create a courtyard with an open and airy structure that becomes part of the garden.”

Whether the swimming pool is already in place or not, D’Tapia recommends that homeowners work with a landscape architect, as well as an architect, to plan the landscape and pool house together. He says pool houses tend to echo the main house, but some homeowners choose to construct a completely different style of building.

“If you’re building on a smaller lot, it’s best to keep the buildings similar, but if you have a large lot you can be more creative with the style,” D’Tapia says.

The Rices worked with GTM Architects to design the pool and pool house as well as the main house.

“George Myers helped us decide to put the pool away from the house so that the house doesn’t create a shadow on the pool,” Lisa says. “We have enough space on the property so that there’s a lawn that’s almost the size of a football field that separates the main house from the pool.”

The Rices’ main house and pool house are Georgian-style and have similar colors and materials. Lisa Rice says they felt symmetry is important.

“Pool houses are usually complementary of the main house, but not necessarily a replica,” Myers says. “It’s nice to have a complementary style so that the entire property looks like a compound with a small villa.”

At a home in Potomac, Rill designed a classic pool house that mimics the home.

“We designed a classical garden pavilion that becomes an object in the landscape and provides a romantic accent to the pool,” Rill says. “In that case, we just have an outdoor fireplace, a lantern on the top for lighting and a pavilion that provides shade.”

Rill says echoing the materials of the main house, such as a stone exterior and a slate roof, ties the pool house together with the primary residence. Landscaping, he says, can be used to create a boundary between formal gardens and lawns and wilder meadows or woods.

“One of the more complicated pieces of designing around a swimming pool is the need for a fence,” Rill says. “You don’t want to feel like you’re in prison, so it’s best if you can place the fence around the perimeter of the property rather than next to the water. At one home in Potomac, the pool house sits between the tennis court and the swimming pool, so we put in a pergola and a custom-designed mahogany gate in the wrought-iron fence.”

At that home, the pergola, or arbor, connects two pavilions, one with a changing area and the other with a laundry room and storage room. The stone used for the pavilions matches the stone around the pool, and the peaked slate roof on each pavilion echoes the roof on the main house.

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In the case of the Parkses’ home, Rill took a different design approach.

“The Parkses’ main home is more traditional, and the pool house has a much cleaner design,” Rill says. “We decided to make it more of a garden pavilion, very minimalist and wide open.”

In Fairfax Station, on a nine-acre site, Nesmith designed a dramatic outdoor living area around a custom swimming pool and a combined pool and guest house. On four stone pedestals, gas-fueled fire-and-water bowls pour water into the pool, and a nearby pergola has a rain-curtain water feature that showers water into the pool. Beyond the rain curtain is a stone seating area with a wood-burning fireplace, and the pool house has an underground garage for storing equipment and Ipe (Brazilian walnut) pergolas on either side, one with a bar and the other an outdoor shower.

“While I always try to bring elements of the existing home into the pool house so there’s a relationship between the buildings, what you can do depends in part on the property itself,” Nesmith says. “Sometimes there are easements and restrictions, especially if there’s a septic field, that drives the decisions about what to build and where it can be located.”

Regardless of the architectural style of a pool house, the project demands careful choices of materials for safety, easy maintenance and the ability to stand up to the weather. Rill says the flooring in most pool houses is often the same as the pool deck to blur the line between indoors and outdoors and to stand up to wet feet and damp towels.

“Even if you build a pool house with an open kitchen, you want to make sure you have a way to close it off to protect it from the weather,” Myers says. “We try to use a lot of stone and tile and to minimize the use of wood because you’ve got wet feet and wet bathing suits around that can damage wood. We do use teak sometimes since it’s more resistant to water damage.”

Designing a pool house that can survive Washington’s summer heat and winter ice and that can function now and in the future for family and friends requires a thoughtful design process with a team of professionals.

Steps for designing a pool house

●Look for inspiration on Houzz.com.

●Think about how you plan to use the space.

●Include a lighting design for evening and nighttime use.

●Consider how the pool and pool house will look from inside the main house.

●Refine the list in the context of your space and your budget.

●Reserve some of your budget for indoor and outdoor furniture and accessories.

●Develop a master plan for the project.

●Check the licenses and experience of professionals before you hire them.

●Assemble a team of architects and landscape architects to integrate the entire plan.

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