The firm, which has more than 550 depots supplying professional tradespeople, has handed chief financial officer Mark Robson the additional role of acting as deputy to chief executive Matthew Ingle.
Group financial controller Theresa Keating, a member of Howdens’ executive committee, has been appointed finance director, which is not a board position.
Caroline Bishop, the firm’s company secretary, will leave the business and be replaced by her deputy, Forbes McNaughton.
Howdens chairman Will Samuel said: “Howdens is a very successful company, and much of its success is due to its management culture and business model.
“As part of the continuing development of the company we are putting in place these changes to enable its further growth and development and to ensure its ongoing success.”