Strandsend Ltd has lost another planning battle to build a residential development in the grounds of Cornelscourt House, a protected structure on the Old Bray Road in Cabinteely, Dublin 18.

Strandsend, whose directors are Brian Durkan, Anthony Durkan and Geraldine Carter, lost its first party appeal to build four six/seven-bedroom houses in the grounds. In its appeal, Strandsend said a number of similar developments in the Dún Laoghaire-Rathdown area have been granted permission by the board, including Eaton Brae House in Shankill, Ridge House Hall in Glenageary and Riversdale House in Rathfarnham. It said the pattern of allowing some residential development within the grounds of large protected residences "has long been established in planning and conservation practice".

It argued that the proposed development provides for a landscaped area between the development of four houses and the main house "which maintains the visual separateness currently experienced at the site".

However, An Bord Pleanála refused planning permission because of the mass, scale and height of the proposed development and its location in the mature landscape garden area fronting Cornelscourt House. It said the development would be seriously detrimental to the character and setting of the protected structure and would result in the loss of mature trees that are worthy of retention.

Strandsend bought the 929sq m (10,000sq ft) Victorian property, which was originally built for a Church of Ireland rector, for around €4.3 million four years ago.