An Bord Pleanála has given Gonzaga College on Sandford Road in Dublin 6 the thumbs up for a massive extension that will include an art gallery and exhibition area and a two-storey lecture theatre.

The fee-paying Jesuit school has also got planning permission for a projection room, dining hall, 11 classrooms, two kitchens, green rooms, office toilets, a new entrance to the rear, and changing rooms.

The 3,909sq m (42,076sq ft) development will also include a weights training room, a computer room, social area, and a new internal road in the grounds of the college, as well as an additional 27 car-parking spaces.

Cowper Grove Residents Association opposed the development saying in its appeal to An Bord Pleanála that the area to the west of the site is a "Residential Conservation Area". It said that, while the extension to the school is of high quality, there has been little consideration of the impact of a ring road upon the adjacent residential area which would result in a loss of trees.

The college responded that the anti-clockwise route around the school would facilitate emergency access to school buildings.

An Bord Pleanála ruled that the development "would not seriously injure the amenities of property in the vicinity, would not be prejudicial to public health, and would be acceptable in terms of traffic safety".

The all boys school, which opened in 1950, featured in a Department of Education report last year which found that the number of enrolments in private schools have increased, with Gonzaga College up by 45 per cent, while those for non-fee paying schools are in decline.