Case Study #6

    During the late 1980’s, David Brown-Kinloch acquired an abandoned brick house in a residential neighborhood in downtown Louisville. David renovated the house to make it super-insulated, and it now benefits from passive solar heating, cooling, and lighting. The house, which was originally built during the 1880’s, uses the sun as its primary heat source and uses natural daylight instead of electric lighting during the daytime.

When David acquired the house, it’s long south face had good exposure to the sun, but consisted of two solid brick walls with few windows. Very little direct sunlight entered the house, so David added a row of windows along the top of the south-facing wall. To do this, he removed the southern half of the gable roof, and mounted windows on top of the brick wall. The gable roof became a shed roof with an overhang designed to shade the windows during the summer, while allowing the low winter sun to stream into the house.     The home’s brick walls suit the passive solar design very well. They provide excellent thermal mass, which heats up slowly during the day and then releases its stored energy back into the house at night. The high ceilings and windows allow incoming sunlight to fall on the north wall (which consists of the original brick), warming it and diffusing light throughout the house.

The thermal mass also helps to keep the house cool in the summer. The overhang prevents direct sunlight from entering the house from May through August, allowing the brick walls to maintain lower indoor temperatures.

    Two important features that support this home’s passive solar design are the six inches of foam insulation that were added to the exterior of the house and window insulation panels. Without this insulation, the heat provided by the sun in the winter would flow back outside right through the walls and windows. Two inch thick foam panels are used to insulate the windows at night. A switch automatically closes all of the panels simultaneously, and they are opened manually by pulling a rope attached to each panel. The exterior foam insulation is covered by cement stucco, which was applied directly to the foam.

    David and his wife Cindy have been living in their home since 1986 and have been very pleased with its solar features. Their home illustrates what can be achieved in densely populated urban neighborhoods, and with older homes that at first glance don’t seem well-suited to passive solar design.

PASSIVE SOLAR WATER HEATER

    A passive solar water heater provides most of the family’s hot water. It is located in the ceiling above the bedroom and consists of two recycled water heater tanks painted black. The water tanks are supported by the roof rafters and are heated by sunlight that enters through the high windows installed atop the south-facing wall of the house. This home-made unit requires no pumps and functions simply under the pressure in the water lines. Whenever a hot water tap is used in the house, hot water is drawn from the tanks, which pulls new cold water into them.

    Passive solar water heaters are vulnerable to freezing if they are located outdoors in climates where winter temperatures reach 32^o F, which is one reason they are not used more commonly in Kentucky. Kinloch skirted this problem by locating the water heater inside the house, where it would only freeze if the house itself dropped below freezing.

   LARGE WINDOWS, high on the south-facing wall, run the length of the house, providing ample sunlight in the house during the heating season.

   ROOF OVERHANG along the south-face prevents direct sunlight from entering and overheating the house from late spring through early fall.

   INSULATED WINDOW SHADES retain heat in house on cold nights.

   INTERIOR BRICK WALLS provide thermal mass to store heat in winter and keep house cool in summer.

   EXTERIOR WALLS insulated with 6” FOAM INSULATION and covered with stucco.

   Windows provide ample diffuse DAYLIGHT, minimizing need for electric lighting during daytime.