A glass-topped console table next to an L-shaped sofa divides kitchen from living space in Mike Johnson’s condo. Placement of rugs and furnishings is key to making a home look bigger and avoiding clutter, he says (Katherine Frey/THE WASHINGTON POST)

Downsizing from a four-bedroom house to a one-bedroom condominium led interior designer Mike Johnson to get creative about living small. Within his 725-square-foot penthouse in the District’s Shaw neighborhood, Johnson applied the tricks of his trade to make the home seem larger without sacrificing his collection of mid-20th-century furniture and artwork.

“My home represents the way I design — a modern look in a neutral palette,” says Johnson. “Since there weren’t many defined spaces in the condo, I needed to think about creating a great look for different functioning areas within the unit. It allowed me to push my ideas and have fun.”

The former owner of Sixteen Fifty Nine, a Georgetown shop specializing in vintage modern furnishings, Johnson now works for District designer Lori Graham. “I was a big fan of Mike’s store from the day the doors opened and grew to rely on it for unique finishing touches during project installs,” says Graham. “One of his strengths as a designer is a keen eye for composition, be it the composition of a room or a vignette within the room.”

Johnson closed his store in March 2011 after business declined during the economic slump. “It started getting slow in 2009, picked up in early 2010, but by June 2010 it tanked and never recovered,” he recalls.

About the same time, the designer’s personal life underwent a major change. He and a longtime romantic partner decided to separate in 2008 and sold their remodeled 1920s house in Cleveland Park and most of their furniture. Johnson then rented an apartment before buying his current home in 2010.

Mike Johnson decorated his penthouse condo with some items from his former store, including the glass vase behind him. (Katherine Frey/THE WASHINGTON POST)

The Shaw penthouse, part of a multicolored structure completed by District architect Eric Colbert in 2008, typifies the open-plan layout of newer apartments in the city. Kitchen, living and dining are part of an open room entered directly from outside the unit.

“I wanted a space that was clean, simple and modern,” Johnson says. “I didn’t want to do a lot of renovations.”

Adding his own touches

But true to his design interests, he made several improvements to put his stamp on the condo. Leaving the raw concrete ceiling and bamboo floors intact, he added track lighting in the living area and, in the kitchen, installed a bold pendant fixture and a glass-tile backsplash.

In the hallway between his bedroom and bathroom, the designer removed closet doors to create a wallpapered niche for a desk. “When I first lived here, I still owned a business and needed a place to work at home,” he says. “I didn’t need the extra closet space.”

Within the condo’s main space, Johnson separated its various functions through the judicious placement of furnishings. He achieved the effect of a foyer separated from the kitchen by wallpapering an alcove next to the front door and hanging a mirror over a Danish bench upholstered in faux crocodile.

A glass-topped console table pushed up to the back of an L-shaped sofa divides kitchen from living space. At the end of the room nearest the windows, a square wooden table and four 1930s chairs provide a place for dining and card games.

Subdued tans, browns and grays unify the furnishings “so the eye travels everywhere in the room and doesn’t stop at a bright color,” says Johnson, who recommends buying major furniture pieces in neutral shades for small spaces.

Art as color accent

In the living space, he limited vivid hues to an abstract painting purchased on a buying trip to Indianapolis. The only other spot of intense color is a humorous canvas depicting a circle of cannibals hanging in his kitchen.

“It’s easier to get a bigger bang for your buck by putting the color into the artwork and accessories,” the homeowner says. “If you get tired of those in a year, you can replace them without having to spend a lot.”

In his living area, different fabrics and finishes create subtle variations within the neutral color palette. A velvet armchair rests next to bronze-colored stool, ceramic lamp and a 1960s walnut console for the TV. Leather ottomans and marble-topped side tables are pulled up to the tweedy sofa. “I love mixing textures to create depth in a room,” says Johnson.

Much of the visual interest in the main space stems from the displays within the floor-to-ceiling bookcase stretching from the kitchen through the living space. Johnson hired a carpenter to build out two existing columns and add a third pier to create recesses for the shelving.

Within the bookcase, the first-edition books, prints, paintings and small objects collected over the years by the designer are organized into eye-pleasing arrangements. One shelf holds an array of prints depicting industrial scenes while another features a painting of a sunbather purchased in London. Small artworks and a starburst mirror found at a Paris flea market are clustered on the opposite wall.

“It’s a technique that I used in my store to organize the merchandise into vignettes and create greater visual impact,” the designer says. “When I create these groupings, I follow the rule of thumb of doing them in odd numbers, putting three or five objects together rather than two or four. It looks better.”

Bedroom’s cozy retreat

Separated from the living area by a rolling door, the bedroom is carpeted and decorated in somber colors to intensify the cozy factor. Walls are painted in Benjamin Moore’s “Briarwood” to match the gray upholstery of the bed.

“I was trying to get a clubby, den-like feel, to make it feel like it had been here for a while,” says Johnson of the sleeping space. “That goes along with the tight placement of furniture.”

An armchair placed next to the foot of the bed and a dresser holding another TV provide just enough room to reach the walk-in closet, office area and bathroom. Tall 1950s lamps on walnut nightstands mediate between the height of the headboard and a rosy abstract canvas hanging above it.

In furnishing his condo, Johnson recycled some of the vintage designs from his former home and mixed them with new pieces from shops in his neighborhood. The bed, a chrome side table and living room rug are from Mitchell Gold, the rug in the entryway was purchased at Timothy Paul and the Eero Saarinen-reproduction side tables next to the sofa were bought at Room and Board — all stores on nearby 14th Street. “I like to support local businesses as much as possible,” says the designer.

This summer, Johnson joined the commerce on 14th Street in selling vintage pieces through a new design emporium opened by his employer. Showroom 1412 sells Graham’s custom furnishings alongside other high-end furniture brands and Johnson’s midcentury wares, including lamps, vases and artwork.

“The store allows me to keep in touch with old customers and go on buying trips and look for great finds,” says Johnson. “The thrill of the hunt was always the best part of the business.”

Deborah K. Dietsch is a freelance writer.

Mike Johnson’s tips on making a small space seem bigger:

●Define living and dining areas through the placement of furniture and rugs. “A big open space can look cluttered and ill-defined without the right organization.”

●Don’t be afraid to use dark colors in a small room. “They can make the space seem much cozier and more inviting than if you paint it white.”

●Hang drapes at the ceiling even if your windows aren’t floor-to-ceiling. “They make the space seem taller by leading your eye to the ceiling.”

●Continue the color palette and design style from room to room. “Doing midcentury modern in the living room and traditional in the bedroom makes the spaces seem disjointed.”

●Assemble collectibles into large clusters. “Don’t spread your collections all over the apartment. It’s better to group them together in one place for more impact.”