John Blackburn of Blackburn Architects brushes Gunda under the watchful eyes of Bonnie, bottom left, inside a horse barn at All's Well Farm. (Richard A. Lipski/For The Washington Post)

You know you live in a wealthy country when someone earns a comfortable living as an architect for horse barns.

John Blackburn, 66, is that guy. He is also a productive businessman who loves being his own boss.

Blackburn runs a six-person staff in a 3,000-square-foot office near Washington’s Dupont Circle that grosses between $1 and $2 million a year designing barns across Virginia horse country and the world.

His client list includes regular folks as well as successful horse lovers such as Under Armour mogul Kevin Plank, Washington Wizards/Capitals co-owner Fredrick D. Schaufeld and two big philanthropists: the late billionaire John Kluge and the late real estate scion Robert H. Smith. He designs homes as well, and the jobs include notable clients such as the Shriver family and local businessman Mitchell Rales.

His barns usually cost between $1 to $3 million to build, depending on the number of stalls and how fancy the client wants to get with materials. Slate roofs, brick floors and oak paneling tend to raise costs. Pine is cheaper.

“My whole shtick is designing for the health of horses,” Blackburn said. “For horses, in particular thoroughbreds . . . you want to design barns to ventilate naturally.

“As soon as you take a horse out of nature and put it in a barn or paddock, you are asking for trouble. Your barn is functioning as Mother Nature, and you control the environment and health of that animal. If you don’t do it properly, you run the risk of hurting your horse.”

So Blackburn, who has a coffee-table book in the works titled “Healthy Stables by Design” (Plank is writing the forward), designs his barns to approximate the outside weather while still protecting the horse.

“You tend to design the barns to retain a little bit of the heat that horses give off. You don’t want a horse in a draft. You want the temperature within six to 10 degrees of the outside temperature. If it’s 30 outside, you would like it to be 40 in the barn. Horses can take cold, but they can’t take heat.”

Most of Blackburn’s barns have a lot of skylights, which heat up and create a chimney effect by pulling the heat from the floor of the barn. The rising heat creates natural ventilation, keeping the horses comfortable.

His southern horse barns tend to be built with concrete blocks because the material stays cooler and keeps termites away. In northern climes, he uses more wood because it is less costly and there is less mildew and rot than in the steamy South.

Blackburn lives in the Chevy Chase neighborhood of D.C. and has five architects and a bookkeeper at his firm. Everyone gets health care and bonuses, even if the bonuses shrink in the lean years.

The company, Blackburn Architects, works in 30 states but concentrates on the East and West coasts. It collects a fee that is 8 to 10 percent of the total cost of the project. So a $2 million horse barn may yield his business $200,000.

Blackburn draws a six-figure salary; the amount depends on how strong business is that year.

“I always wanted to own my own business,” Blackburn said. Working without a safety net keeps him motivated.

“The fear is a motivator,” he said. “You don’t have a business organization and boss to care for you and provide security.”

Entrepreneurship came naturally to Blackburn, who grew up in east Tennessee working for his father’s books and magazine wholesale company.

He graduated from Clemson University and arrived in Washington in 1972 after graduate school at Washington University in St. Louis.

“I figured Washington was recession-proof,” he said. “It also had a great base of nice, old buildings that need renovation.”

He found work at a succession of firms, all the time keeping an eye out for someone who shared his ambition for starting his own business.

“I needed a partner to bounce ideas off and give me security,” he said, “while at the same time giving me some flexibility.”

He found a partner at one of the firms, and they started on the third floor of a Georgetown townhouse in 1983. Blackburn kept his old job until their practice took hold.

They soon got a call from a landscape architect who had been hired to create a master plan for Heronwood Farm, a horse farm near Middleburg that philanthropist Bob Smith had purchased. The architect knew someone who knew someone who knew Blackburn and his partner.

“They were looking to hire an architect to design the barns and other farm structures,” Blackburn said.

Blackburn and his partner — neither of whom had designed a horse barn — moved fast, photographing more than 100 barns and buildings across Middleburg and Northern Virginia. They presented a series of sketches to Smith, and they got the job to design seven buildings, including horse barns, staff residences and service buildings.

More jobs followed through local press and word of mouth. A big break came from Kentucky horse breeder and businessman Will Farish, who was once ambassador to the United Kingdom under President George H.W. Bush. Farish asked him to design a series of barns through the late 1980s and early 1990s.

Clients such as Farish helped him tap deep into the horse crowd, a connection which he has maintained for the past three decades.

The biggest challenges in that time have been two recessions, one in 1992 and another in 2008. One client in Dubai canceled a project during the depths of the financial crisis. He weathered both recessions by diversifying into the renovation of older buildings around Washington.

When I caught up with him recently, he was driving to Sagamore Farm near Baltimore. Sagamore is one of the country’s legendary thoroughbred breeding farms, established by the Vanderbilt family and being resurrected by Under Armour’s Plank.

Like I said, it’s a wealthy country.