The £10 million Hostry project, which was recently approved by the city council, follows on from the practice's previous award-winning visitor facilities scheme, also built within the cathedral close (below).
The first floor of the new building will house a community room, with seating for over 200 people, as well as a music library.
The ground floor will boast a new visitor entrance - through an existing medieval arch - and an 'Encounter Space' to host the Cathedral's programme of temporary exhibitions and an education suite.
Partly funded by a £2.3 million Heritage Lottery Fund grant, the building will be constructed from oak and limestone and will have underfloor heating and natural ventilation.
According to the practice, the building aims 'to recreate the volume of the medieval Hostry that stood on this site, while making as little impact as possible on the fabric of the existing buildings and archaeological remains.'
Work is scheduled for completion for Christmas 2008.