Climatron_Feedback Drawing
Murphy and Mackey with St. Louis Engineers Synergetics, Inc, St. Louis, Missouri, 1960



In the late 1950s, Dr. Frits Went, from the Missouri Botanical Gardens, commissioned a design for a new greenhouse to display a large collection of tropical plants. The bid went to the architectural firm Murphy and Mackey, who partnered with St. Louis engineers Synergetics, Inc. to design a geodesic dome, using Buckminster Fuller’s principle for structural geometries. Known as “Climatron,” the large domed greenhouse was completed in 1960, and achieved several records: it was the first fully air-conditioned greenhouse in the world, the first geodesic dome to be clad in Plexiglass, and eventually listed by the AIA as one of the 100 most important buildings in US history.

Climatron housed over 15,000 types of tropical plants in the non-native environment of St. Louis’ climate. To achieve the sustenance of this wide and diverse plant life in the unnatural climate, the entire dome was air-conditioned to best simulate their native environments. Mechanical engineers Paul Londe & Associates designed two different air systems to counter the effects of summer and winter (the two most extreme conditions inside the greenhouse). The first was a ducted system for heating and humidity control in the winter to simulate tropical solar heat gain. The second was a blower-spray system, which allowed for evaporative cooling and humidification similar to tropical summers. The entire system was controlled by the Data Center, which controlled the air supply and hydration systems, lighting, and even bird calls.

Though the building was a technical and structural innovation for 1960, in 1989 renovations required the replacement of the Plexiglass and some of the aluminum elements. Humidity had created infiltration in the panels, and the glass itself had yellowed. Engineers J.A. Morgan and Associates designed a new enclosure which utilized heat tempered laminated glass panels. The Saflex lamination ensured that in case of destruction, the glass will stick to the film itself, eliminating the risk of shattering. The renovation required the fabrication and fixture of 2,425 glass panels and cost 6.24 million dollars. It reopened in March of 1990. In 2010, the Climatron celebrated its 50th anniversary, remaining one of the largest standing climatically controlled geodesic structures..


KEYWORDS: Evaporative cooling, Steam heating coilsPyrolytic coating


DECREASED SOLAR GAIN: The Plexiglass yellowed over time, decreasing possible solar gains required by vegetation.

INEFFICIENT OVER TIME: The Plexiglass and aluminum warped, allowing condensation, precipitation, and air to filter through the structure, rendering the Climatron inefficient due to increase loads on mechanical systems.

PANEL REPLACEMENTS: The degradation of the Plexiglass necessitated a 6.24 million dollar renovation less than 30 years in to its life. During this renovation all 2,425 plexiglass panels had to be replaced.