Preston Murdoch Geren, Sr., architect and engineer, was born in Sherman, Texas, on November 2, 1891, the son of James Preston and Maria Fearn (Putman) Geren. He earned a bachelor of science degree in architectural engineering from the Agricultural and Mechanical College of Texas (later Texas A&M University) in 1912 and served as supervising architect for buildings on the A&M campus for two years after graduation. From 1914 to 1916 he was partner in the Austin firm of Giesecke and Geren. At the beginning of World War I he entered officers' training at Camp Leon Springs and was commissioned first lieutenant in the United States Army Corps of Engineers. Geren took part in the battles of St. Mihiel and the Argonne Forest, where he was wounded and received the Purple Heart and the Croix de Guerre. At the end of hostilities in 1919 he joined the contracting firm of J. F. Johnson of Austin, where he served as chief engineer until 1921. He was professor and chairman of the Department of Architecture and Engineering at Oklahoma State University from 1921 to 1923. Geren was chief engineer for the Fort Worth architectural firm of Sanguinet, Staats & Hedrick (see SANGUINET AND STAATS and HEDRICK, WYATT C.) from 1923 to 1934; he worked on such Fort Worth landmarks as the Fort Worth Club, the Texas and Pacific Passenger Terminal, and the Fair and Electric buildings.
Geren organized his own architectural and engineering firm in 1934 and was joined in partnership by his son, Preston M. Geren, Jr., in 1949. The firm was responsible for designs, additions, and remodeling of many outstanding structures in Fort Worth and throughout Texas, including Arlington Heights Senior High School (1936), Elmwood Sanitarium (1937), Farrington Field (1939), the Bank of Commerce and Riverside State Bank, Matthews Memorial Methodist Church (1948–49), Travis Avenue Baptist Church (1959), and Ridglea United Methodist Church (1964–65). In 1938–40 Geren was associated with five other Fort Worth architects on the city's first two United States Housing Authority public-housing complexes. He also designed the New London High School (1938), Greater Southwest International Airport (1953, with Joseph R. Pelich), Colonial Country Club (1955, with John Floore), and numerous buildings at the University of Texas at Arlington and at Austin, Southwestern Baptist Seminary, North Texas State University, Texas Wesleyan College, University of Dallas, Texas Woman's University, and Texas Christian University. He was associate architect to Louis I. Kahn of Philadelphia for the Kimbell Art Museum (1968–72). During World War II Geren maintained his architectural and engineering practice, and, in joint venture with Wiley G. Clarkson, J. R. Pelich, and Joe Rady, participated in the design of McCloskey Army Hospital in Temple (1942), Harmon Army Hospital in Longview, and numerous airfields and other defense facilities in Texas. Geren's other principal works include the Fort Worth National Bank Building (1957), the Mutual Savings and Loan Association (1958), the First National Bank Office Building (1961, in association with Skidmore, Owings and Merrill), and the Equitable Savings and Loan Association Building (1961), all in Fort Worth, and Midland High School in Midland (1961).
Geren was a charter member of both the Texas Society of Architects and the Fort Worth Chapter of the American Institute of Architects. He served on numerous Fort Worth city government boards and committees. He was a director of the Fort Worth Chamber of Commerce, the Fort Worth Symphony Orchestra, and the Better Business Bureau. He served on the city's first building code committee (1928) and was its chairman in 1958–59. He was chairman of the City of Fort Worth Zoning Board (1940–46). Geren was twice awarded the Distinguished Award (1951, 1959) of the City of Fort Worth for outstanding contributions to the city codes. In 1957 the Texas Construction Council awarded him a Certificate of Merit. He was selected Engineer of the Year by the Texas Society of Professional Engineers in 1956 and was elected a fellow of the American Society of Civil Engineers in 1959. The mayor of Fort Worth proclaimed February 5, 1969, "Preston M. Geren, Sr., Day" in recognition of his unprecedented service to the community and to the construction industry. Geren was a high-ranking Mason and a member of St. Andrew's Episcopal Church, the River Crest Country Club, and the Fort Worth Club. He married Linda Giesecke of Austin on June 14, 1921, and they had three children. He died in Fort Worth on September 21, 1969.