He has directed the rehabilitation and restoration of a number of national register and national landmark properties including projects for the State of Georgia and National Park Service and projects participating in the state and federal historic preservation tax credit programs.

Jack has served on the board of directors of the Georgia Trust for Historic Preservation and Docomomo/US. He served as chair of the American Institute of Architects Historic Resources Committee and is currently President of the ICOMOS International Scientific Committee for 20th Century Heritage.