Situated in downtown Portland, The Louisa is a residential high-rise apartment building with 242 apartments including ground floor retail.  The building reflects the design vision of developers, architects and landscape architects, while responding to the needs of the tenants and reaching sustainable goals. The center of the retail podium houses an intensive and an extensive green roof which reduces storm-water runoff, mitigates the urban heat-island effect and provides visual interest when viewed from the upper floors.

The Louisa also features high-efficiency glazing and balconies on the south, east and west sides, which double as shading. Other features include operable windows that allow for natural ventilation, water efficient fixtures such as dual-flush toilets, low-toxicity building materials and finishes such as agrifiber cabinetry and bamboo flooring, an interior recycling facility, and the use of recycled content and locally-sourced construction materials and finishes.  The Louisa also supports various forms of transportation: regional light rail, the Portland Streetcar, several bus stops are within a few blocks, and a bicycle-commuter locker room is provided.

Because the Louisa was planning for LEED certification, the objectives for the project were outlined early on through the LEED process.  Apart from requirements of certification, the design team felt it was important for the green roofs to reach out to the surrounding neighbors by providing an enjoyable tapestry of plant textures and patterns for viewing. The intensive green roof is 100% accessible and programmed to allow residents to have outdoor parties and barbeques.

The intensive growing media has a 12-24 inch depth, composed of sand loam, pumice and organic matter (compost). The total costs of the green roofs (including membrane, insulation, drainage, growth media, irrigation pavers and plants) were $15 per square foot for the extensive portion and $25  per square foot for the intensive area. Environmentally appropriate landscaping, with drought-tolerant and native species, populate the intensive and extensive green roofs. The area of the intensive green roof gardens is 8,071 square feet.

The roof gardens are reviewed four times per year by a landscape maintenance contractor.  The primary beneficial maintenance task is the manual removal of weeds in lieu of herbicidal removal of nuisance plants. The fertilizers used contain no phosphorous. Water is judiciously applied with a low volume drip irrigation   system only during the summer months when the evapotransporation rates are at their peak. The green roofs are being     monitored by landscape architects along with the maintenance contractor to verify long-term soil composition changes, plant health, and irrigation balancing.  The  information gained will be used to inform the design and maintenance teams for other green roof projects.

These green roofs have been on display for countless tours by professionals in the sustainable design industry, soil scientists,  horticulturists, landscape architects, city   officials from Portland and other cities on the west coast.  In addition to the numerous other sustainable strategies included at The Louisa, the benefits of the green roof are conveyed to residents via a Green Resident Manual which they receive upon moving in

Lush and flourishing, the Louisa has grown into a beautiful and accessible              residential green roof system, one which is well-integrated into the design and      philosophy of the building, embracing an ethic of sustainability from conceptual design to ongoing maintenance.