Circa Morris-Nunn designed the extension to St Marys Cathedral Narthex in 2011, loctaed in the heart of Hobarts CBD. This new extension comprises of a new four storey high extension creating a space for the new functional tower to group all the new rooms together. This space includes Parish Offices and meeting, a Ground Floor lobby with amenities for informal gatherings after mass, a crypt to receive all the cathedral's archbishops, and a music performance space. This new extension has been designed with the intention to be reminiscent of ‘the great medieval Chapter Houses found as an integral part of many Gothic cathedrals’ and the overall octagonal form resembles the traditional chapter houses and this space traditionally housed the Assembly space where the governing body of the Church met. Morris-Nunn won the 2013 The Alexander North Award for Interior Architecture Australian Institute of Architects (TAS) in 2013 and the Public Architecture Commendation Australian Institute of Architects (TAS) in 2012.