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On Monday, Oct. 15, 1934, ground was broken for the construction of a community and school gymnasium/auditorium at Peshtigo, Wis. The architect incorporated a new structural framing system for the roof that would ultimately gain widespread acclaim. The new system, structural glued laminated timber, had been used in Europe for over 30 years prior to its first application in America: the Peshtigo school gym.
EUROPEAN BEGINNINGS
Glued laminated construction had its beginning at the turn of the century when Otto Karl Freidrich Hetzer (1846-1911) of Weimar, Germany, obtained his first patent for this method of construction. This 1901 patent, granted in Switzerland, was for a straight beam composed of several laminations bonded with adhesive. Wolfgang Rug, in his 1994 article "Innovationen im Holzbau-Die Hetzerbauweise" states that "Hetzer" beams of 10 meters length (32 ft. 6 in.) were used as early as 1890 in the Reichstag building in Berlin. In 1906, Hetzer received a German patent for curved glued laminated construction, signaling the true genesis of clear span timber arch construction. Patents were sought and granted in several European industrialized nations. Hetzer's 1922 promotional catalog Hetzerholzbau lists the countries where the method had been utilized: Austria-Hungary, Belgium, Czechoslovakia, Denmark, England, Finland, France, Germany, Holland, Italy, Norway, Spain, Sweden, and Switzerland. The firm Otto Hetzer A.-G. was incorporated in 1901 and included Hetzer's three sons: Karl Paul, Walter Ernst, and Otto Alfred. The Hetzer System, as glued laminated timber became commonly known, was exhibited in the form of a 43-meter- (135-ft.-) span building at the 1910 Brussels World Exposition, where it received two Grand Prizes. At the 1913 International Building Materials Exposition held at Leipzig, this method received a Gold Medallion.
The earliest and most prodigious development occurred in Switzerland. The ingenuity and drive of firms such as Turner and Chopard of Zurich were responsible for the promotion and quick acceptance of glued laminated timber. By 1920, there were over 200 buildings using Hetzer arches and beams in the country.
Denmark received its introduction to glued laminated timber in 1914 when H.J. Kornerup-Koch began producing the product under a Hetzer license. Engineer Guttorm N. Brekke (1885-1980) was responsible for bringing the technology to the Scandinavian peninsula. He purchased the patent rights to the Hetzer system for Norway...