I bought a kitchen from B&Q in November 2011 that included a 5 year workmanship guarantee. The door to the dishwasher was fitted too tight when installed. Over the years of use it has gradually pulled away from the inner part of the door and was not closing fully but now has finally broken. B&Q refuse to do anything about it. If it was just a case of buying another door that would be fine, but this will definitely happen again due to the installation being poor. What are my rights?