The steel beam original to the building was left exposed but toned down with gray, flame-proof paint. It runs the length of the flat, delimiting the passage area.

White was used extensively throughout the addition, a choice that the architects say enhances the spacious feel of the rooms and draws attention to the views.

The semi-closed entryway contains a white cabinet for storing coats and scarves. The LED ceiling lights are from Contrast Lighting.

The renovated house is outfitted with a sauna.

The kitchen features a distinctive cantilevered countertop.

A new staircase turns a corner at the large stone chimney, an element of the original house that the designers were careful to preserve.

A clear railing follows the stairs to the second floor.

The architecture firm Open Form and the interior design firm Clairoux collaborated on this modern update of a 1950s-era house in Laval, Quebec, north of Montreal.

A radiant hot water heating system was installed under a new concrete floor slab above the old foundation. It was coated with epoxy — light gray for the common areas, white for the bedrooms and bathrooms — then finished with matte polyurethane.

The architects and interior designers did away with the home's cramped, darkened layout and recast the interior as an open space defined by clean lines.

The apartment originally crammed four closed rooms and a kitchen and bathroom into 1,000 square feet. After the renovation, it had only one bedroom and a large, open kitchen.

The same space before it was updated.

Emilie Bédard and Maria Rosa Di Ioia of EM Architecture gave Erik Rydingsvärd’s top-floor apartment in a Montreal triplex a subdued, modern look that evokes his native Denmark. The range hood and satin-finished teak cabinets are by Kastella. The floors are Douglas fir and the walls are spruce, painted white.

The industrial stair leads to the upper level, where the bedrooms, bathrooms, and play space are located.

In the Dolomite mountains, an angular copper-clad apartment building echoes the topography of its site. Photos by Hertha Hurnaus

Thellend Fortin Architectes designed this two-story addition in the OUtremont neighborhood of Monteal to capture views from the steeply sloping lot.

A vintage stool, a design that once was a staple of Greek classrooms, is tucked under the office desk on a landing leading to a balcony. The visual theme of the vertical wooden slats repeats itself here, including on a closet door. “They have no handles,” Ritenour says of the closet doors. “The lines are the door handles; you have to know to grab them.”

This revamped Montreal flat includes a rooftop sauna lined with torrified, or dried, cedar. Outfitted with glass paneling and oriented to capture views of Mount Royal, it is the ideal haven for this hardworking homeowner.

The open observatory.

A wall-mounted fireplace is a dominant feature in the living room.

A view of the backyard through the kitchen.

A floor-to-ceiling wall unit accommodates a fridge, stove, oven, and convertible custom cabinetry. The pendant light is from the Multi Luminaire showroom in Pointe Claire, Quebec; the appliances are from Bosch and Miele.

Di Ioia and Bédard designed the wrought-iron spiral staircase that leads to the rooftop terrace and sauna as a visual nod to Montreal’s signature outdoor stairways.

The cantilevered extension is clad in anthracide-colored concrete panels that reflect the limesone that was used to line the swimming pool.

The architects sited the patio and swimming pool beneath a canopy of mature maple trees, an element that they say makes the site "an oasis in the heart of the city."

The addition was conceived as a "ribbon" that both hugs and runs lateral to the contours of the existing building, offering multiple vantage points from which to admire the surrounding landscape.

The sleeping cubbies lie beneath the walkway connecting front and back units. Cedar decking and soffit add warmth and texture to the transitional space.

In an 850-square-foot loft in Montreal, Quebec–based firm Gepetto built understated, custom cabinetry to suit an aging couple's needs. Here, the Murphy bed that folds into a larger walnut storage unit. The wall, which also conceals a washer and dryer, does double duty as a partition between the bedroom and the loft’s entrance. Modern Murphy beds like this one often incorporate sleek lines constructed in dark-toned woods.

Vassiliou and Angeliki tuck into watermelon slices on a patio off the master bedroom. The terrace offers views of Mount Lycabettus, whose peak towers 745 feet above Athens, and the city itself, which splays out toward the mountains in the distance.

No whiteware here. In this moody apartment in Berlin, multi-toned charcoal gray subway tiles make up the backsplash, which contrasts with the pop of rosy color on the kitchen cabinets.

Piet Hein Eek's wooden chairs add a touch of color to the monochromatic Amsterdram apartment of Hunter Hindman and Shelby Carr.

Greenery bursts out to the street from the side yard of Paul Bernier and Joëlle Thibault’s home.

The renovation revealed a 30-foot-deep well beneath the bedroom, which the team half-jokingly considered turning into a fish tank. Instead, they opted for a simple bedroom with plenty of built-in storage.

Thin, delicate LED lighting is suspended from the ceiling, giving the display cases sharp, focused illumination.

The refrigerated, black steel display cases were custom designed and fabricated. The compressors for each unit are located in the basement, allowing the cases to stand on delicate legs and preserving the minimalist look of the space.

A band of hemlock slats runs the length of the shop along the ceiling, hinting at the assemly-line production process and nodding to the archetype of the wooden pallet or conveyor belt.