Loewen has been a board member and chairman of Economic Development Winnipeg, a council member of the Institute of Chartered Accountants of Manitoba, a board member and president of the Big Brothers and Sisters Association of Winnipeg and president of both the Manitoba Chamber Orchestra and the Linden Woods Community Association. He has also been involved with the United Way of Winnipeg, serving on the United Way Cabinet from 1994 until 1999 as Chair of the Major Corporate Division and Deputy Chair of Business. He is a founding Director of the Business Council of Manitoba.