A Dalkey man is challenging a proposal to renovate Santa Maria (a protected structure) on Cunningham Road, Dalkey because he says it will irretrievably alter the house which is of "architectural, historic and social importance".

In his appeal to An Bord Pleanála, John Bolton with an address on nearby Cunningham Drive, also disputes that the proposed works to Santa Maria are "minor" as described in the planning application.

He says they have a floor area of over 66sq m, (700sq ft) including a partially glazed double height extension with an internal mezzanine floor and provide for the division of the protected structure into two dwellings.

Santa Maria, formerly called Enderly, was built by noted Dalkey builder John Cunningham in the 1890s.

Playwright Hugh Leonard's father worked as a gardener on the estate when it was owned by the Jacobs family and couturier Marjorie Boland bought it after the second World War and changed the name to Santa Maria.

Bolton says the current planning application is the latest in a series "leading to a step by step alteration of the nature and amenities of the protected structure".

In July a group of investors paid over €20 million for a ready-to-go site to the rear of the house with planning permission for 24 homes in the rear garden of the Victorian house.

It had previously been purchased at auction in 2005 by developers Wesley Curran and Graham O'Donnell of Otranto Properties for just under €10 million.

It is believed that the developers intend to sell the house - which stands on 0.6 acres - after it is refurbished.