"Kelvin only had a year to go on his contract and we would have risked losing him for nothing if we kept him and there is also the fact that we need the money at the Club.
"Kelvin wanted to play Premiership football as well so it was a move that we couldn't resist for a number of reasons. I would like to put on record my thanks to him for his two years service at Portman Road.
"He has been magnificent for us since he first arrived and proved himself as the best 'keeper in the Championship last season, something that was recognised by his peers."