There’s a party going on high above the traffic of downtown Washington. On roof decks in Shaw and balconies in Dupont Circle, people are gathering at the end of the day to welcome summer.

The urban view is awesome from the penthouse terrace at Bob Williams and Stephen Heavner’s Logan Circle one-bedroom condo, where they opened the season last week with drinks and dinner for a dozen friends and colleagues.

The dramatic outdoor space, a 45-by-12-foot expanse, is accessed by a spiral staircase and is furnished as carefully and comfortably as the stylish 1,200-square-foot space below. After all, Williams is co-founder and president of design at furniture company Mitchell Gold + Bob Williams; his husband, Heavner, vice president of operations for the Velvet Foundation, a nonprofit that is creating a national LGBT museum in Washington, is a lifelong gardener.

On the polished terrace, three outdoor rooms are defined by planters of lavender, artemisia and daylilies, a tiny herb garden and a miniature succulent meadow. The pale blue, charcoal-and-white Sunbrella sink-down sofa cushions beckon visitors to linger over coffee or a cocktail. The bonus: Guests get to soak in a skyline of historic rowhouses, cranes putting up new buildings, church spires, plus other Washingtonians enjoying the evening on their own terraces.

Read: Six tips from Williams and Heavner on outdoor entertaining

“The deck gives us so much extra space for entertaining,” says Williams, 53. “Once the sun starts going down and moves to the other side of the building, it’s shady and pleasant and there’s a nice breeze up here.”

Last week, the couple threw their first party since their landscaping project was completed. They hired caterer Susan Gage and worked with her to come up with a summer menu. Guests gingerly navigated the twisting metal stairs up to the terrace, balancing tumblers of strawberry rhubarb sangria. They were welcomed with wasabi peanuts, artisan cheeses and toasted pimento cheese mini sandwiches and a well-appointed bar cart. Later, Gage arranged an indoor buffet of shrimp on grits, pulled pork barbecue, balsamic watermelon and yellow tomato salad and star-shaped cornbread. (They decided it was better to serve the food inside on this hot evening.) Guests could choose to dine inside or head upstairs to the terrace.

Heavner and Williams bought the condo in November as a Washington base. They already owned a spacious house in Hickory, N.C., near Taylorsville, where Williams and Gold’s $150 million furniture company is based. But Williams travels constantly for work and Heavner was spending more time in Washington working for the foundation. There is a Mitchell Gold + Bob Williams store on 14th Street NW, and another just opened at Tysons Galleria.

The place would be an urban retreat, small yet suitable for corporate and fundraising events as well. “We wanted something compact and modern, but with an outdoor space and a view,” Heavner, 51, says. This condo has an open-plan kitchen, dining and living area and a bedroom, full bath and powder room, with walls of windows. No surprise, Williams shopped his own store for most of the furniture, using a Franco sectional in off-white as the anchor piece. They tied in the same fabric on the dining chairs and the upholstered bed.

Outdoors, a driftwood-finish wood sofa and chairs conveyed from the previous owner. New cushions were made in colors to coordinate with the blues, silvers and grays of planters and plants in the landscaping plan. “We happen to know some great upholstery people,” Williams says.

Heavner took the lead in overseeing the plantings and design of the terrace. They hired Dupont Circle landscape designer Robert Bell of Bell Design, known for his inventive, small city gardens. “They wanted a sort of English urban garden and entertaining space with different zones,” Bell says.“We worked together closely on the concept, where we took elements of a traditional garden and used an unexpected color palette.”

As party guests came up the stairs, they stepped outside and into the first of three outdoor rooms, an open breathing space to take in the view and experience the small “lawn,” which is actually a carpet of sedum. As they passed the bar, they entered the lounge area, with comfortable places to sit and chat and have appetizers. The final space features a dining table and chairs sheltered by a large umbrella, with a nearby herb garden of thyme, dill and rosemary.

The focal point of the terrace is the 6-by-12-foot wall sculpture that Bell designed, incorporating an aluminum frame with a steel matrix fitted with hinged pieces of foils made of brass, stainless steel, copper and zinc. The design is based on a section of one of Alexander Hamilton’s eyes as depicted on the $10 bill. “I was looking for something iconic to tie in Washington,” Bell says.

Guests who take in views from all sides of the terrace can’t help noticing that the tip of the Washington Monument is visible from one corner.

Next gathering on the calendar: a Fourth of July fireworks-watching party.

See the party-ready Logan Circle perch

Six tips from Williams and Heavner

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