10a Blackrock Road, Portrush, Co. Londonderry, BT56 8EX

10a Blackrock Road, Portrush

A detached two-storey seafront dwelling built around 1910 and divided into two flats circa 1930. Originally constructed as a single house, it was first recorded on the fourth edition Ordnance Survey map of 1922–31. The building is square on plan, facing north, and sits on a steeply sloping coastal site overlooking the sea with vehicular access to the rear.

The house is rendered and painted, with a hipped roof covered in artificial slate and fitted with synthetic ridge tiles. Two rendered chimneystacks with terracotta pots are present. Steel rainwater goods run to boxed eaves. Window openings are square-headed with simple lugged rendered surrounds and keystones, fitted with 2/2 timber sash windows throughout.

The symmetrical north front elevation is three windows wide, with a large central dormer containing paired windows. The lower windows are diminished in size. The east side elevation has irregular fenestration and is abutted by a flight of concrete steps and an elevated glazed porch serving the upper level, supported on reinforced concrete piers. An off-centre dormer window breaks the roofline, and a further door opening at the lower level contains a glazed timber door. The rear elevation is symmetrical on split levels with a central dormer matching the front. The west side elevation is abutted by a further glazed entrance porch supported on reinforced concrete posts, which opens onto an elevated concrete path leading to the rear.

The building was originally a simple rectangular structure with a return wing. When first entered into valuation records in 1910 at £24, it cost £515 to build and was occupied by Annie Keith Stewart and her niece. The five-room house was designated second class in the 1911 census. It was initially known as Upper Cooleen, distinguishing it from another house further along the coast also built by Annie Stewart, called Cooleen. Following Annie K Stewart's death in 1932, the house was divided into two flats circa 1930: the upper flat comprising four bedrooms and a boxroom, sitting room, kitchen, scullery, bathroom, WC, and external washhouse; the ground floor flat containing a reception room, two bedrooms, kitchen, scullery, pantry, bathroom, and WC. Two porches were added to either side of the house around 1930 to provide separate access to the upper flat.

The house currently lies vacant, with permission granted for its demolition and replacement. While it possesses some interesting historical detailing as an example of early 20th-century coastal residential development during Portrush's Edwardian heyday, it is not considered of sufficient architectural or historic interest to warrant listing.