The duplex is a handsome, affordable home; providing owners ease of maintenance, low operating costs and a comfortable, healthful environment in which to live. All spaces as required by the program are provided.
Main living spaces are located on the upper level to meet the constraints of the site and give the greatest access to natural light—a clerestory provides light from above. Also, better views from the main living spaces and greater visibility of the entrance from the street are provided. Since the lower level is partially below ground, a light well is provided.
Vehicles enter the site at the lowest point along the road and descend two feet into the parking lot. The base of the house is four feet lower than the parking lot
The plan is compact with minimal circulation space. The upper level is an open plan, offering maximum flexibility. The entry porch adds exterior living space.
The duplex is designed to meet the goals of Architecture 2030. The strategy to meet these goals consists of employing passive solar design with day-lighting; constructing a well-built home with good insulation, air sealing, and efficient mechanical systems; and incorporating on-site renewable energy.
The house is a rectangular shape, with its long direction along an east-west axis which results in a long south façade and facilitates a solar oriented design.
South Elevation—Upper Level—The South Elevation has glazing amounting to 12 percent of the floor area. Thermal mass was provided for the amount of glazing exceeding 7 percent of the floor area (solar tempered). The area of glazing exceeding the amount allowed for solar tempering amounts to 31 S.F. (five percent of floor area).
South Elevation—Lower Level—The area of glazing was limited to 7 percent of the floor area (solar tempered).
North, East, and West Elevations—The area of glazing was limited to a maximum of 4 percent of the floor area for each elevation.
The thermal mass on the upper level, employed to accommodate the 31 S.F. of solar glazing, should be a minimum of 165 S.F. A multiplier of 5.5 S.F. of thermal mass was used for each square foot of solar glazing. The design of the house provides 307 S.F. of normal weight concrete, 1 ½ inch thick, finished with ceramic tile. This will assist in keeping the house warm in the winter.
Two foot deep overhangs are provided. Using a multiplier of 3.0, the side of the house will be shaded six feet down from the overhang. The window sills are within six feet of the overhang. This will assist in keeping the house warm in the winter and cool in the summer.
The house has continuous insulation on the exterior of the framing and foundation (R7 minimum). This will enable the mass of the house to store energy to maintain constant temperature inside the house.
Clerestory windows are provided to bring in light from as high of a location as possible. As the house is located at the bottom of a hill on a steep north facing slope, a limited amount of light is available, especially in the winter. The clerestory could capture light that would, otherwise, pass right over the house.
Active Solar—Photovoltaic System
The photovoltaic system generates 4.5KW of electricity—300 S.F. of panels, producing an average of 15 watts per square foot