This project involved the re-use of a former NI Water reinforced concrete storage tank to create a new 2 storey dwelling, nestled on the side of Slieve Donard with views over Newcastle Town and the Irish Sea.
The reinforced concrete storage tank was re-used as the ground floor of the property, with openings provided on the perimeter to form windows and provide natural light to bedrooms. An insitu reinforced concrete outer leaf was constructed with a board-marked finish around the perimeter of the tank to improve the aesthetic and enhance the thermal envelope. A large opening was formed in the tank roof slab to allow for a new steel staircase to be installed between ground and first floor level.
A combination of cantilevered insitu concrete slabs and steelwork were added to the top of the tank to form an enlarged first floor footprint. This included a South-Eastern Facing cantilever balcony with stunning views of Slieve Donard to the south and Newcastle town and the Irish sea to the North.
Load Bearing Insitu RC walls with exposed board marked finish (a common theme throughout the property) rise from the new first floor structure to form first floor spaces, which includes a signature 10x10m column free living/kitchen space. A steel roof structure rests on the load bearing RC Walls to cap off this contemporary property. A careful design consideration was the deflection of the steel structure over the kitchen space. Pre-cambers were introduced to the roof steel to achieve allowable deflection limits and to ensure that drainage falls would not be compromised and mitigate against serviceability damage.
Key to forming the additional storey was a carefully considered loading assessment of the existing storage tank structure. With very little record information available, cores were taken through the roof slab and load bearing walls to determine thicknesses and confirm the presence of reinforcement. Historical imposed loads also helped to ‘fill gaps’ in record information. The information gathered allowed for conservative estimates of the existing element capacity and gave us confidence to carry out the required alterations to create this truly unique project.
