Bristol's oldest school has unveiled ambitious plans to transform its city-centre site.

Bristol Cathedral Choir School is set for an £11.7-million revamp funded by the Government's Building Schools for the Future initiative.

Pupil numbers are expected to grow to 700 in the next few years, so the extra space will be needed to accommodate the new students.

The plans include construction of a new building to replace the school's Fortune Theatre, as well as the conversion of a newly built office block bought from developers last summer (known temporarily as Building G).

The announcement of these further projects follows the completion last term of a £3.5m, five-storey building (Building S) in College Square housing facilities including the music department.

Principal Neil Blundell said: "I am delighted to announce these very exciting plans.

"We have spent a great deal of time planning how to develop our facilities in order to provide an environment that is conducive to the highest standards of teaching and learning.

"Once all the work is finished, we will have state-of-the-art facilities for 700 boys and girls across a wide range of subjects and for important extra-curricular activities such as concerts and plays.

"The development will also provide a sense of space that is truly rare in city centre schools."

The former independent school became a state-funded academy in September 2008. Bristol is the first choir school in the country to have become an academy and is heavily over-subscribed for Year 7 entry in September 2009, with five applications for every place.

There are three main parts to the development project:

● Building G, College Square – The office block acquired last summer will be converted to house maths, business studies, ICT and languages. Work is due to start by this summer.

● The Fortune Building – The existing building will be replaced, with work due to start next school year. Plans include provision for a large dining area, theatre and art facilities.

● The Deanery – This historic building currently used for classrooms will be refurbished and will become the academy's reception and administration base.