SMALL SCALE RESIDENTIAL GREEN ROOF AWARD
Project: Edgeland Residence
Location: Austin, TX
Award Winner: Ecosystem Design Group/Lady Bird Johnson Wildflower Center
“The most exciting thing about this project was the merger of the green roof with the surrounding landscape. Often times green roofs serve more as an experiential nod to nature, but Edgeland blurred the lines so that the house and landscape were truly one. If we, as designers, embrace such opportunities when they present themselves we can create a real positive change in our urban environments and actively thread ecosystems throughout our cities.”
John Hart Asher, Ecosystem Design Group/Lady Bird Johnson Wildflower Center
The Intersection of Nature and Structure
Edgeland House is located on a rehabilitated brownfield site in Austin Texas. It is a modern re‐interpretation of one of the oldest housing typologies in North America, the Native American Pit House. Like the Pit House’s of the past, Edgeland's insulative green roof and 7‐foot excavation into the ground keeps it cooler in the summer and warmer in the winter.
The Edgeland project is about healing the land and ameliorating the scars of the site’s industrial past. The project raises awareness about a diminishing natural landscape and its finite resources by creating a balance between the surrounding industrial zone and the natural river residing on the opposite side of the site. The surrounding 4 acres were restored back to a climax Blackland prairie consisting of native grass and wildflower species replacing the former dominant invasive plants that occupied the site.
The simple act of pushing the landscape back to this former ecological condition provides habitat for local fauna, water cleansing, carbon sequestration, and improves air quality. The design team extended the prairie right onto the roof so that landscape and building merge into a seamless condition that eliminates the traditional figure/ground concept.
Over 75 species of native grasses and forbs occupy the roof and include a mix of pioneer and later successional species. Many green roofs have failed in Texas' semi arid sub tropical climate due to extreme temperature swings, sparse rainfall and the use of inappropriate non-native sedum species. Edgeland's herbaceous species mix and green roof media were developed through 10 years of green roof research by the green roof designer. The prairie species chosen for this project can deal with the harsh Texas climate and the growing media possesses materials that promote water retention and regulate temperature to prevent spikes during both summer and winter months. The green roof growing media also consists of recycled local materials.
The judges praised this project for its incredible architecture and fantastic integration of green roof as critical component of building operation and aesthetics. They were impressed by its integration into the local landscape and ecosystem, with a contrast of modern design and natural setting.