Clark PH Townhouse 1

South-facing rear facade with exterior shades down and closed to shade all direct sunlight.

Clark PH Townhouse 2

Exterior shades down but tilted open to permit views and admit daylight while still blocking the heat of the sun.

Clark PH Townhouse 3

Exterior shades raised to permit full sun into the building and unfiltered views to the rear yard.

Clark PH Townhouse 4

View from the kitchen towards the rear yard with the exterior shades raised.

Clark PH Townhouse 5

Primary bedroom with the exterior shades lowered but open to admit daylight and permit views without unwanted heat.

Clark PH Townhouse 6

Similarly, a South-facing clerestory window at the top of the stairs admits winter sun but not summer heat.

Clark PH Townhouse 7

Exterior terraces and deck at the rear yard.

Clark PH Townhouse 8

Front facade and vertical extension.

This project proposes a gut renovation, enlargement, and Passive House technological upgrade to an 1890’s red-brick townhouse with unused FAR and an exceptionally straight and sound exterior shell but an interior mistreated past repair. The investor-owners recognize that an investment of this magnitude is a one-time opportunity to change the energy footprint of the building. Compelled by the economics and performance of Passive House they purchased the property with this construction methodology specifically in mind.

As a Passive House renovation of a historic masonry townhouse, the project faces typical challenges which the local community has developed expertise in solving. New work cannot be added over the outside at most of the exterior so insulation and air barriers are meticulously constructed from the interior. Interior steps in the thickness of the exterior walls and the mating of the new structure onto the top of the existing demand unusual consideration against thermal bridging. Water vapor drive in the permeable exterior brick is managed carefully with redundant system design, rigorous detailing, and construction execution.

Like all Park Slope houses on the East side of the street, the rear façade faces both the interior of the block and South. This happily means that large new windows in the rear façade can simultaneously open the house to the leafy back yard and bring in the maximum possible amount of warm winter sunlight, desirable for both its contribution to heating the house and it’s lovely feeling. Summertime heat is easily blocked by shading the high summer sun, which shines primarily on the roof: classic passive solar design. This project further proposes exterior shades over this rear glazing. These shades, placed at the outside of the window, have the added capability to harvest the sun’s visible light and reflect it inwards to daylight the interior while excluding all of its heat.

A new third floor and a deeper cellar make a modest-sized home significantly larger for a contemporary purchaser. Aesthetically the design proposes to highlight what is left of the historic structure by contrasting it against the new work, rather than diminish it through an inevitably doomed attempt to recreate vanished craft.

The result preserves a portion of historic Brooklyn and brings it forward as a comfortable and ultra-low energy house for the future.