This project comprises of a single storey vertical extension to an existing three storey building. The roof structure to the new extension is formed using exposed timber rafters with glazing between each rafter on the north elevation. Concealed timber connections were detailed for the roof rafters to maintain a simple but elegant appearance. A roof terrace area is also provided to the new single storey extension, accessed via a bespoke steel spiral staircase. All work was undertaken with the offices and retail unit below fully occupied.