Greg Johnson has been employed in the Minnesota construction industry as a carpenter, contractor, or estimator since 1982. He joined the City of Saint Paul as a building inspector in 1994 and has served on numerous code development and regulatory policy committees including, most recently the National Green Building Standard developed jointly by the National Association of Home Builders and the International Code Council, (ICC).

Johnson is certified as a building official by the State of Minnesota and as a building inspector by the ICC. He is in a second term on the Board of Directors of the ICC and his third year of service as the Chairman of the ICC Education Committee.