A Sustainable Brownstone Transformation in Brooklyn

Add to
By Alexandra Lange
How do you make a Brooklyn brownstone more sustainable? First, get rid of the brownstone.

The street facade of New York City’s first certified Passive House, known as Tighthouse, is clad in pale gray stucco, sculpted with a few historic-looking details. But, if you knock on that wall, it sounds hollow: The stucco is merely the outermost layer in a 20-inch-thick insulated sandwich. The original brick is buried deep inside, where it can do no harm—via chinks, cracks, or settling—to the supersealed box this 19th-century, 3,120-square-foot Park Slope house has now become. The cornice, too, is a lightweight contemporary replacement: a hollow fiberglass shell mimicking a wood original.

Join the Daily Dose Mailing List

Get carefully curated content filled with inspiring homes from around the world, innovative new products, and the best in modern design

A Sustainable Brownstone Transformation in Brooklyn - Photo 1 of 8 -

Julie Torres Moskovitz, who designed New York’s first certified Passive House, recently finished her first book, The Greenest Home (Princeton Architectural Press), about the first wave of ultragreen homes in the United States (following the 40,000 already constructed in Europe). The title hits shelves in May 2013. Here, a custom stainless steel stair with treads of perforated steel replaces the old wood staircase in the rehabbed Park Slope brownstone.

The smooth, low-maintenance surfaces are a far cry from the derelict three-story row house designer Julie Torres Moskovitz first saw in 2009. The brownstone’s front facade was pocked and cracked, the back wall was falling apart, and the interior left a warren of mystery rooms (including one lined with a one-way mirror). The owners, a young couple just starting a family, weren’t daunted by the damage because they wanted a clean, modern renovation to showcase their art collection. "The owners say they don’t like anything organic," says Torres Moskovitz. "Only concrete and steel."

A Sustainable Brownstone Transformation in Brooklyn - Photo 2 of 8 -

All of the Jenn-Air appliances, including the washer and dryer, are electric, as the owners asked the city to cut the gas line to the house. The kitchen cabinetry is from Ikea and features custom matte gray doors and Silestone countertops. The floorboards are reclaimed maple from an old tire factory, sanded and stained gray.

A Sustainable Brownstone Transformation in Brooklyn - Photo 3 of 8 -

Torres Moskovitz designed custom stainless steel recessed boxes, fitted with LED strip lighting, for the stair landings.

The original idea was a net-zero house. "That concept starts with using less rather than producing more," says one of the owners. "We wanted to put less stress on the communal infrastructure." He began researching Passive Houses, visiting an early iteration in Philadelphia and collecting consultants’ names, including Torres Moskovitz of the environmentally focused Brooklyn design practice Fabrica 718. At his encouragement, Torres Moskovitz completed Passive House trainings in New York and Dublin; she is now a certified Passive House tradesman.

A Sustainable Brownstone Transformation in Brooklyn - Photo 4 of 8 -

The clients nixed a powder coating on the stair treads, fearing it would wear away, but approved it for custom, gray steel vanities in the master bathroom. Bathroom floors look like poured concrete but are actually thin, troweled-on microtopping.

Passive House certification is performance-based, focused not on any renewable or recycled materials used but on how efficiently the building breathes, heats, and cools. That meant that much more than the original facade had to go. Torres Moskovitz specified triple-glazed, argon-gas Schüco windows and doors for the front and back. On the parlor floor, the windows have the same tall, lean proportions as those of traditional brownstones, but they are mullion-free and have a special coating that helps warm the house in the winter. Within the white walls, mounted on studs and insulated with medium-density foam, the windows have been individually sealed with an Intello Plus membrane and Tescon Profil tape. "It’s akin to gift-wrapping," says Torres Moskovitz. "The materials cost about $3,500, and it took two weeks to seal every window." The owner and the architectural designer had to seal a window themselves to convince their contractor, generally an ally, that it was worth the extra elbow grease.

A Sustainable Brownstone Transformation in Brooklyn - Photo 5 of 8 -

The rear facade, like the top-floor addition, is faced in rectangular panels of black rainscreen Richlite over exterior mineral wool insulation.

Torres Moskovitz describes her clients as "members of the iPhone generation. They think everything should be as intuitive, as simple, and as low-maintenance." Given the high standards for the Passive House envelope, they wanted to spend their budget on the exterior and were willing to economize on finishes inside. "The house was built in 1899, and in those 100-odd years no one had ever substantially renovated the infrastructure," says the owner. "This was our big chance to make changes." To make those interior economies look good, the home’s materials palette was left minimal, assuming the clients’ art would provide color later. "Julie did a fantastic job with the architecture," says one owner. "Those beautiful moments don’t need accentuating."

A Sustainable Brownstone Transformation in Brooklyn - Photo 6 of 8 -

While the proportions of the old brownstone’s facade remain congruous with others on its street, the stone has been replaced with stucco over foam. When knocked, it sounds entirely hollow.

A Sustainable Brownstone Transformation in Brooklyn - Photo 7 of 8 -

The designer added a 500-square-foot third floor—hidden from the street—with a small, bluestone roof deck, to create a master suite. The roofline was reoriented due south and covered in a combination of solar thermal panels by Stielbel Eltron (to heat the domestic hot water) and Unirac SolarMount SunFrame with 190w photovoltaic panels (for electricity).

One such moment is the decision to open up the back of the house with larger, north-facing windows in the open kitchen. This might seem like a no-no—more glass has the potential for more heat loss—but the Passive House Planning Package, a proprietary energy-modeling software, makes it easy to weigh trade-offs. Even more light is filtered into the dark center of the row house via a three-story light well, which creates catwalk-like hallways on the second and third floors.

A Sustainable Brownstone Transformation in Brooklyn - Photo 8 of 8 -

All that remains of the original interiors is a multistory brick wall that stretches up three floors from the center of the parlor. But even this is less authentic than it appears: The owner wanted a respite from the white and gray and requested an exposed brick wall. But brick parti walls are often leaky, due to old mortar and irregular repairs. So the contractor made the real parti wall airtight with a paint-on sealant and then built a new brick wall in front, reusing brick from the two disassembled chimneys. Why no fireplace? Think about it, Torres Moskovitz says: "It’s essentially a hole through your house."