A native of Pittsburgh, Knavish earned a Bachelor of Science degree in mechanical engineering and a Master of Business Administration degree from the University of Pittsburgh.
He joined PPG in 1987 in an engineering role in the former flat glass business and advanced through positions including process engineer, supervisor of technical services, manager of operations planning and scheduling, and superintendent of production across PPG's former flat glass and automotive glass businesses before joining the architectural coatings business in 2000 as plant manager for the East Point, Georgia, manufacturing facility.