Canyon Edge home offers affordable sustainability
The Canyon Edge house, located in San Antonio, Tex., exemplifies the kind of work done at Hurt Partners Architects, such as designs that are highly responsive to their sites and contexts, in this case a suburban neighborhood on the city limits of Austin accessible only by car. In addition, this home demonstrates careful liaisons between the overall design concept and the interior spaces, such as kitchens and baths, and artful detailing of standard materials. To see a slideshow of this home, click here.
For this speculative project, Hurt Partners built a modestly-sized, sustainable family house that fully interacts with a challenging site which slopes dramatically from the street to a dry-creek bed below. The home sits on a small plateau 10 feet below street level and is protected from the street while enjoying a serene view through the canopy of trees below.
The spaces are arranged along the natural site contours around a central living/dining area whose generous roof separates from the roof datum of the house, and reaches and bends itself into the carport roof toward the street in a gesture that invites the owner -- arriving by car -- into the experience of the living room and trees beyond.
Our first effort towards building affordably was to design a modestly-sized house, giving as much quality and function in 2,100 square-foot house as possible. The house is efficient in use of space, yet open and generous in feel and offers an alternative/counterpart to the many sprawling suburban houses that might be vying for our spec buyer’s attention. The house provides smart efficient spaces (office, closets, and bathrooms) which are interlinked with the adjacent spaces resulting in minimal circulation space and to maximize functional spaces.
The project features include the following:
Modest size: Among many strategies, a major consideration for achieving a sustainable design was to build a modestly-sized house. The house was developed as a 3-bedroom, 2-bath spec house at approximately 2,100 square feet. The rooms have their own kind of luxury being thoughtfully, smartly designed and always resulting in dynamic spaces and geometries.
Passive solar design:Architects used large overhangs in all sensitive areas to prevent solar gain, and also built a large masonry thermal wall on the west side where the house is dug into the side of the hill. This thermal wall is connected to the slab and – in the summer months -- is always in shade, and thus provides a thermal cooling mass to counteract the hot Texas climate. In the winter, the mass serves to store heat for the occasional periods of cold air temperature.
Efficient HVAC system design: Through our work over the last years, we have learned that the HVAC ducting design is one of the most important areas where we can substantively impact the energy consumption of a building. For this project we designed a single-trunk duct system with minimal duct runs to the discharge registers for all living and sleeping spaces, thus eliminating most of the inefficiency and energy loss due to duct travel and inefficiency due to turns. Placing the duct system inside the air-conditioned envelope, we made this efficiency element into an architectural feature by housing it in a fur down over the hall access, intentionally compressing the space and making the transition to sleeping and the living areas more dramatic. The 7’-6” circulation space opens -- with steps down and a ceiling jump above -- into each space.
Roof elements, use of SIPS panels:For the roofs, we used structural insulated panels (SIPS) with a standing seam metal roof for optimal solar reflectivity. The SIPS panels reduce the need for additional structural elements such as roof trusses, while providing an exceptional R-value and working well within our aesthetic desires of having a thin roof line cut into the sky.
Solar collectors: The house is equipped with a fully functional 6 Kw solar panel system which contributes up to 60 percent annual energy savings for the resident. The house is also designed for a future rainwater collection system which will provide substantial reduction of household grey-water use.
Design and placement of windows in bedrooms:We wanted to consistently reinforce the serene experience of the view into the canopy of the trees; thus, we carefully placed the windows in the bedrooms -- lower than we typically would -- to best connect the view to a person sitting in a chair or sitting/lying in bed where the owners would spend most of their time in these rooms.
Carport roof gesture:The design on this sloped site allowed us to rethink the typical relationship of the car to the house. We introduced the car into the central experience of the house by pulling it under the roof and virtually into the living space. The roof shape directs the homeowners’ view – as they approach the house in their car – through the living space to the principal natural experience of the house: a stunning view into the tree canopies. At the same time, though the cars are visible from the living areas, they are not aesthetically overbearing as they are high in the space. Interestingly, when a car approaches at night, the car lights shine on across the living room ceiling announcing arrival.
Materials: We used many standard, off-the-shelf materials such as gypsum board, standard wood trim, aluminum flange windows, concrete floors, and conventional affordable doors. But we also used other materials which were affordable but less common finish materials such as: exposed CMU block, inside and outside, to eliminate additional finish materials and expense; simple exposed, painted structural steel, Parallam wood floors (a pressed wood and glue product and milling by-product which is normally hidden in walls but for this project became a rich-textured floor) at an affordable price.
Tigerwood, which resists outdoor elements and moisture, gives the carport and living roof its beautiful and warm texture and is also used in the master bathroom as the vanity cabinets stretch into the shower area. These elements work together as a composition which balances and contrasts warmth against a certain edginess and rawness. Our goal was to expose the inherent beauty of all these materials in the way they are placed next to one another.