19 April 2007

Missouri Solar House -- north

Armstrong's design for a passive solar house for the Missouri climate and culture became the foundation for his continuing development of residential designs. Armstrong's decision to orient the house with its main entry facing toward the north allowed for a relatively modest, understated formal expression toward the public view. By locating the primary yard and view toward the south, Armstrong was able to feature full height glazing along the entire south wall of the house.

The motivations for providing such extensive glazing were multifarious. In part there was a desire for visual openness and connecting the interior space to the exterior landscape. Glass helped to reduce the perception of solid walls as physical and psychological boundaries holding the benefits of nature at a distance.

The use of double pane glass in passive solar design was based upon the so-called "greenhouse effect" where light falling upon glass would heat the interior space with the glazing trapping the heat inside. The thermal benefit of south-facing glazing was certainly of value in the midwest where winters can be bitterly cold. The idea of warmth and comfort in the midst of winter was particularly appealing and was a focus of Libbey-Owen-Ford's advertising of this product. The benefits were primarily physical and psychological, though the reduced cost of heating a home in wintertime was also touted. However, at the time the demand for new housing outstripped the relative availability of heating fuels. Consumers chose from the traditional, but dirty coal or oil burning furnace or the newer, cleaner natural gas. Electric heating wasn't far behind with the advent of the "all electric home."

While the thermal benefits of a passive solar home were tangible and measurable in financial terms, the relatively low cost of heating fuel made this issue moot in the eyes of the general public. The arguments for extensive glazing were more convincing when based on its perceived aesthetic, health, and cultural benefits.

In promoting the concept of the passive solar home, Libbey-Owens-Ford was particularly careful to separate arguments for any particular architectural style although glass walls were clearly advocated by the modernists.

In the immediate post-WWII years, there was competition between the various forces promoting the best approach to providing mass housing for the great number of people starting families at the time.

Missouri Solar House -- south

Armstrong's design for a Missouri passive solar house was commissioned and published by the manufacturer of Thermopane glazing, Libbey-Owens-Ford Glass Company. The book, entitled Your Solar House, featured forty-nine solar house designs from architects from the continental United States as well as the District of Columbia.

While the book was clearly motivated by marketing considerations, it presented ideas relating to passive solar house design to the general public.

The company had originally developed double-pane glazing in the late 1930s and brought it to market around 1938. The product caught the interest of architects in various parts of the country who wished to use more extensive glazing, but were concerned with excessive heat gain in the summer and cold drafts during wintertime. Double pane glazing helped to combat these problematic aspects of the extensive use of glass. Additionally, the use of glass was associated with the ideas and philosophy of modern architecture, promoting natural light, open space, and uniting inside and outside.

At some point around 1940, Libbey-Owens-Ford decided to remove double pane glazing from the market due to failure of the seal between the two panes of glass. When the seals failed, the trapped air space between the panes would absorb the humidity of the ambient environment. With the rise and fall of temperatures during the course of a day and over the course of the seasons, moisture would begin to condense on the interior surfaces of the two glass panes. Once the units became fogged, it became impossible to clean and clear them, so the company had to replace those units since they no longer provided a clear view to the exterior.

The apparent problem was the material used for the perimeter seal. Their design relied on an organic material as the sealant. With repeated temperature fluctuations and the resulting expansion and contraction of the separate glass panes. The differential movement was due in part to the success of the technology in the sense that the units would keep the two panes of glass at different temperatures. The higher the temperature, the greater the expansion of the glass pane, even though the actual dimensional difference was visually negligible. The repeating differential pressure on the seal and associated cycling temperatures caused the organic seals to detach prematurely from the glass panes.

Libbey-Owens-Ford needed to overcome a pre-existing skepticism created by the earlier promotion and subsequent withdrawal of the product from the market. They realized they needed to reassure the public of the product's benefits in addition to convincing the architects who would be specifying the material and putting their reputation behind this new technology.

The book was designed to provide a strong argument for the use of thermal pane glazing and in the particular the application of passive solar design concepts to homes located throughout the United States.