Proposed alterations to, and within the curtilage of, an existing Protected Structure, no.5 Martello Terrace, Sandycove, Dun Laoghaire, Co. Dublin, consisting of the following principal elements: 1. New single storey over basement extension to rear incorporating existing basement courtyard; 2. Replacement of existing conservatory to rear with new single storey structure; 3. Internal repair and refurbishment works; 4. Alterations to the existing external hard and soft landscaping; 5. Refurbishment of original windows and replacement of non-original windows; 6. New opening in existing gable wall of the return at first floor level to provide new window overlooking the garden; 7. Installation of Solar Panels to the roof; 8. The development will include all associated drainage and site development works.