Refurbishment of a Piled Commercial Building

One Triton Square was originally a six­storey commercial building with a single level basement located within the Regents Place development near Euston, London. The building was a concrete frame, with steel cores at each corner. The floorplate was approximately 72 x 72 m (236 x 236 ft) with a 36 m (118 ft} wide octagonal central atrium. The original building was well suited for extension due to relatively recent construction standards, high original live load allowances, its large central atrium, generous escape stairs provision and extensive record information. Plant space requirements at basement and rooflevel were maintained. The preferred scheme was the addition of three storeys to the existing six-storey structure and an eight-storey partial infill in the central atrium area, with a further allowance for completely filling in one or two of the lower atrium levels. This allowance was included in the design to offer enhanced flexibility to future tenants. It was clear from an early stage that the foundation load demand would increase to serve the enlarged building area, which increased the existing building floorplate by 70% or 130,000 sq ft (12,100 m2) of commercial space. Maintaining the basement headroom and accessibility for servicing plant would also be important.