The role, where he will work alongside Yummy Pub Co. managing director and BII chairman Anthony Pender, and other directors Jason Rowlands and Tim Foster to identify opportunities for growth, will see him donating his salary as chairman to the Live Your Life charity partnership with Team Margot.
Knowles said: "I've been a friend to and a fan of, Anthony and the Yummy Pub Co for a long time - so I was delighted to be asked to take on the role of chairman. Combining their youth and my experience will kick start a mutual growth process for us as individuals, and it will be a great part of the Yummy Pub business journey."
Anthony Pender, managing director of Yummy Pub Co. added: "Keith has been instrumental in our work with the BII, so it really is a thrill to see where we can go as a team - pairing our company ethos with Keith's creative thinking."
Knowles will continue in his role as CEO of Beds and Bars, in addition to his duties as chairman of Yummy Pub Co.