Louis J. Aubert changes wall colors scores of times a year -- for other people's houses.

Known in architectural and interior-design circles as "Mr. Colour," Aubert is responsible for the hue of many New Orleans streetscapes, and the mood of many sophisticated interiors.

"People don't know what they're getting into with color," Aubert said. "I'm the guy they call to fix it, like in 'Ghostbusters'."

At his own house, a 1700-square-foot Arts-and-Crafts bungalow in a shady Carrollton neighborhood, change comes slowly.

"I've repainted everything," Aubert said, "but there's not the constant smell of fresh paint in my house. I'll change things around every 10 years or so, but not more often than that."

Aubert spent 13 years in the design department of D.H. Holmes department store in New Orleans. He honed his color sense at the long gone store, and also learned to appreciate "the little old ladies who practically lived at 'Holmses-es,' as they called it."

"When I went on my own, everyone was doing interior design, so I decided to focus on exterior colors. In New Orleans, facade architecture is the most important thing, as most of the stylistic elements are on the street side of the house.

"I look at the exterior, the age and the style of the house. Choosing colors appropriate to a house is like selecting clothes that are appropriate to the shape of your body. With clients, I factor in their personal likes and dislikes, and make decisions based on what they say; but the color scheme has to reflect the basic architecture of the house to really work," Aubert said.

For the exterior of his 1917 house, one of a side-by-side pair built for William Henry Broad, Aubert chose a color scheme based on the typical color placement of that era. The body of the house is white, with accent colors used on key elements such as the dark olive window sashes.

Though Aubert's litany of paint choices can sound like a recital from a Benjamin Moore color chart, his house is calming to the eye. Its exterior has the variety and tranquility of a Japanese garden, mimicking the hues of trees and plantings, while remaining true to a period palette.

"I ventured out with a dark stone-like color for the roof overhang, fascia and rain gutters." he said, sounding almost shocked at this choice. But he struck a firmer tone about other choices: 'mushroom' for the door and window casings, dark brown for the front door itself.

Inside, the home follows a typical bungalow plan: Public spaces such as the living-dining room and kitchen on one side; bedroom and bath on the other. Aubert has made such distinctions even clearer by his color choices.

Living and dining areas are painted a soft putty color; the kitchen is off white with a jade-green beaded-board ceiling. Behind the kitchen, a glass-walled den, back entry, laundry closet and powder room, all added in a major 2000 renovation, are painted Benjamin Moore Super White. The pitched ceiling in the den is color-washed with Super White, and the bookcase is Benjamin Moore's Folk Art, which Aubert said, "reminds me of the spring growth of boxwood."

On the other side, the hall is painted charcoal as a background for black-and-white photographs. The bedroom is painted pewter gray. The study and bathroom are painted off white.

The first thing Aubert did after acquiring the house in 1994 was tear out the carpet in the living room and dining room, which were "disaster areas," he said. In place of carpet he installed alternating boards of 2 -1/4 inch white oak (to match that in the bedroom and hall) and 3-inch-wide Brazilian cherry to create a striped pattern. A 12-inch border of Brazilian cherry unifies the two rooms.

Aubert launched a down-to-the-studs renovation of the kitchen in 2006. The patterned kitchen paneling was inspired by a book on early Arts and Crafts buildings in California. A new door in the adjacent hallway reflects the period style of West Coast architects Charles and Henry Greene.

Aubert recently completed an outdoor living space.

"I wanted it to feel like an extension of the house, not just a deck," Aubert said. "It's a tripartite relaxing area: kitchen, den and 'uncovered porch'."

Surrounded on two sides by the rear of the house and the glass wall of the den, Aubert's outdoor room is further framed by a slatted wall that shields the area from afternoon sun. Sheer curtains, hung from a galvanized pipe, create an evanescent fourth wall.

The decking is highly finished Ipe board, with full-width steps that lead to a stone landing in the garden. Other elements include a box fountain from Restoration Hardware, an oversize ottoman that Aubert treats as a day bed and a pair of metal tub chairs. The outdoor area is a comfortable retreat in cooler seasons of the year, but a visual extension of the den in summer.

"As we all know" Aubert said, "there are times in New Orleans when it is more pleasant to see the garden from inside than to be in the garden."

An enticing part of the view is Aubert's shell collection.

"I have collected seashell since childhood," Aubert wrote in an email. "I had used a number of shell-encrusted pieces in design projects and decided to try my hand at it.??Italian Rococo shell-encrusted pieces are really beautiful, so the first piece was the shell panel on the front of the garden shed.??Layering shells over the hair of the goddess [a bust of Aphrodite on a pedestal] was the next project.

"Projects of this type are really a slippery slope; you complete one and you want to start another."

In 2014, Aubert completed a major commission: Color schemes and designs for the renovated Southern Hotel in Covington. His focus, however, remains on residences, where he relishes the gentle tug between his taste, the owner's style, and the demands of the structure.

If a client hires him, Aubert said, "It's like inviting Miss Manners to your home for dinner."