Delivering a modern look, concrete serves as a long-lasting, hardwearing material.

Architect Alex Gil and his wife, Claudia DeSimio, affixed a 750-square-foot addition to the roof of a 19th-century Williamsburg townhouse, transforming their cramped third-floor apartment into a modern duplex. The original fireplace remains, but has been stripped down to exposed brick, as have the surrounding walls, creating an almost wainscot-like design of exposed brick with flat white drywall above.

Designer Christiane Hogner, Bruxelles

Day, Hachigian, and Sosi congregate on the back terrace at a dining table designed by Day and his brother-in-law, Garo Hachigian.

Onstage, Design Prize Switzerland representatives Michel Charlot, Beat Karrer (of FluidSolids), and Rolf Senti (of Bagno Sasso Mobili/Swiss Eco Tap) will explain their surprising concepts and how good design can benefit our environment. Pictured, a FluidSolids stool.

Jaime: Tree Museum in Switzerland Open since 2010 on the grounds of the Enea Garden Design headquarters in Switzerland, the Tree Museum is a unique and rather poetic concept: a collection of 50 specimen trees, many older than 100 years old, in an open-air museum-like setting designed by architect Chad Oppenheim. Blocks of sandstone set off the sculptural tress, and give the whole place a Zen-like atmosphere. Would love to see it in person some day!

The duplex’s lower level, formerly a railroad apartment, was conjoined with its neighbor and reconfigured to meet the rooftop addition.

Though most of the home's interior comes without a splashy designer's name attached, the bathroom is kitted out with a toilet, sink, and bath/shower from Jasper Morrison's line for Ideal Standard. The cabinets are from an Ikea kitchen system.

The 510 Cabin is one of Leggitt's designs, executed with the help of student apprentices.

A whimsical hand-painted mural by local painter Rob Moss Wilson livens up the bathroom adjoining the outdoor tub.

A green guest bathroom with a vanity designed by Pascali Semerjdian and wood panels by Plancus.

One Day of Design, published by Gingko Press

The library is a collection of art, architecture, design, and photography materials. The essays analyze the system and methods to make the library a publicly accessible resource for interdisciplinary discussion. The art library collection started when it was donated as gift from book collector Daniel Rohner.

Despite a tight site, light floods into every room, including the restroom in the guesthouse.

Remarkable Swiss Waterfront Villa: Just five minutes outside of Lugano, architect and interior designer Mischa Groh meticulously constructed Villa Cigno. With spectacular views of the lake and Mount San Salvitore, this newly built home is a contemporary masterpiece. Presented by Fontana Sotheby's International Realty.

The owners toured this home, which surrounds a mature tipu tipu tree, while visiting relatives for the day. The brick is original to the 1947 construction.

The stairwell leads to the main dining room and kitchen, where gray plaster and oiled larch wood joinery create a softer environment. The custom dining table, built by GRG Carpenteria, is surrounded by a set of Philippe Stark Toy armchairs.

The renovation of this old stone structure by Wespi de Meuron Romeo architects was, at times, as much archeology as architecture. The small square in front of the building, the only in the village of Scaiano, dates the building, a former brandy distillery fortified with both spiritis and stone walls. After reinforcing the roof and replacing the wood beam floors with concrete, the team started to dig in.

This alternative view of the kitchen and dining area, outfitted with KWC ONO and Sanitär Tröesch, exemplifies how reinforncing the walls and cutting through some of the stone brought significant light into the interior.

Walter Gropius's office, with furniture created by the students, was divided into two areas within one square space: a workspace and a communication space. The space designed for communicating (shown) allowed students to speak to Gropius eye-to-eye rather than across a desk. The current room is a reproduction of his original office.

Like the stübli, the top-floor bedroom is meant to be moody. Tuckey designed the bed, the brass wall light is by John Glew Architects, and the chair is another piece inherited from the previous owners, a couple who lived there for decades.

The former cellar, now an entrance with a built-in raw steel fireplace, welcomes guests. Plaster outlines the new staircase, where an old stonewall was cut out to provide a passageway to the upper level.

The end goal, a vacation home with a view of the nearby lake, led Jérôme de Meuron to cut through a wall and ceiling to open up the space. "We tried to preserves as much as possible," he says. The addition of the large upper story window adds daylight without altering the street-level character of the stone home.

Residents serve anything they wish, ferrying the food by any number of ways—from lowering sandwiches by basket to inviting patrons into their homes and handing them plates.

The morning after our day at Manly Beach, we took The Essential Tour, a one-hour guided tour of the Opera House during which we learned a ton of information about the structure and its history. (I highly recommend it if you're headed Down Under.) I snapped this photo, showing a view of the Sydney Harbor Bridge from outside the Opera House, before we met the group for a tour.

Happy Canada Day!

Despite the raw materials and rocky walls, the upstairs terrace feels positively weightless, offering spectacular views of Lago Maggiore.

Parts of the interior still maintain an earthy, subterranean atmosphere. Catacombs are hidden below the finished rooms above. The stairs lead to an outdoor area designed for communal interaction.

Dramatic floor lighting on this glass wall, custom fit within the curve of a carved-out stone wall, provides simple beauty in material contrast. "In such small spaces, it's often better to integrate the furniture and fixtures into the room," says de Meuron.

A new coat of glazing (and a bit of a modern paint job on the exterior) brings a clawfoot bathtub back to life.

Meret Aebersold waxes lyrical about one of his favorite cities, Zurich, Switzerland.

Custom case work and a polished wall give the bathroom a warm yet minimal look.

Dwell's Manhattan Home Tour, which showcased five modern homes from the Upper East Side to Chelsea, also took place today. @npzstudio shared a picture of their pass in anticipation.