Mid-Century Modern Prefab Addition

A creative couple builds a prefab addition in their bare backyard, featuring modern design and office space.

By: Elizabeth Beeler

1950s Design

The modular structure' steel-based construction technique is similar to the method implemented by California-based architect Pierre Koenig in the '50s for the case study house #22. Large floor-to-ceiling windows connect the interiors with their environment and allow tight quarter to feel more spacious. The argon, double-paned windows maximize natural light– and energy-efficiency.

Porch Panache

On the 48 square-foot cantilevered deck, a blue bench makes a colorful statement. Recessed LED lighting illuminates the space after dark, while weather-resistant gypsum board clad beneath the cantilevered overhang protects against inclimate weather.

Industrial Railings

A series of simplified metal cables serve as porch railings. Held in place with basic fasteners, the sensible approach suits the structure’s modern ethos. "We chose the cable-style railing to maintain the openness of the deck and promote air circulation," says Celestino.

Metal Siding

The "Think Tank's" corrugated metal Galvalum cladding is locally purchased. Held into place with mechanical fasteners, the siding is durable, inexpensive, and easy-to-clean.

An Inviting Entry

The entry's solid core door with stainless, industrial hinges and a commercial-grade lever makes a sunny statement from the exterior. It's zany orange hue was selected to maintain a common thread with the interior palette.


Blank walls set off of a single work of art, allowing it to become the focal point of the western facing elevation. Its muted palette tames the office's modern look.

Eco-Chic Carpet

The couple selected floor tiles comprised of recycled materials. Available in almost every color, the tiles can be combined to form patterns. Celestino and Cornelia chose these floor tiles for their budget-friendly price point. They laid the tiles underfoot in pattern that mimics their company logo.

Personalized Shelving

Above dual workstations, industrial shelving lined with art and mementos lend the space a personal feel. Black and white photos, a vintage camera and a toy kaleidoscope provide layers of interest. Memorabilia reflects the homeowners' personalities and add interest.

Conference in Style

Opposite the workstations, a retro conference table makes a stylish statement. High-backed wooden chairs with orange seat cushions reiterate the room's color scheme. Whether used on walls, ceilings, floors, or furniture, natural wood brings warmth and softens the look of any space.

Bold Lighting

Above the conference table, a hip pendant fixture suspended from a cloth cord adds a soft glow after hours. Its bold orange hue draws the eye upward, placing emphasis on an often-overlooked space. Strategically placed lighting is a critical element to any well-designed office space.

Smart Workspace

Side-by-side desks allow Celestino and Cornelia to collaborate on projects and make efficient use of the small space. Desk chairs scored from yard sales add vintage flair and keep the room from appearing overly utilitarian.

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