Coming to Princeton from Exeter, he majored in architecture, joined Dial, and worked with the Campus Fund Drive and Theatre Intime.
He joined Armstrong World Industries in 1955, later earning an MBA from Penn State. He managed development work for Armstrong’s Building Products Group. John received several important patents during his career and moved to London for several years in the mid-1970s to establish a product-development group specifically for Armstrong’s European markets.
By 1993 he retired from Armstrong and opened his own consulting firm, Hemphill Interior Technologies. He was also board chairman of the Advanced Building Systems Integration Consortium, located at Carnegie Mellon University.
John is survived by the love of his life, Sarah, whom he married in 1958. They had 59 years of the kind of marital companionship for which we all yearn.