The Kensington Forum Hotel, a 28-storey building in the heart of Kensington, London, is currently undergoing an extensive refurbishment to update its façade and modernise its interior. An extensive solution was needed to support a scaffold structure without using the existing concrete floor slabs.
An initial detailed structural assessment evaluated the capacity of the existing reinforced concrete elements—slabs, beams, columns, and foundations—to support the scaffold loads. The assessment specifically targeted Levels 0, 2, and 8, where the building's ability to accommodate the necessary scaffolding did not meet the minimum requirement for its safe support. Based on these findings, a steel frame was designed at levels0, 2, and 8 to provide a base support for the scaffolding, using conventional steelwork sizes throughout the design to optimise overall project efficiency.
On level 2, the steel frame is supported by UC stubs resting on the existing reinforced concrete columns. Our checks revealed that four columns failed to meet strength requirements due to increased loading, necessitating a temporary back-propping arrangement between levels -1 and 1. A key challenge involved managing load distribution at the foundation level. Given a limiting bearing capacity of 80 kPa set by archived 1970s drawings, a support structure resembling a sloping picture frame was designed to spread the load across a larger area. This solution underwent rigorous checks and received approval through a Category 3 design review, with special consideration given to the proximity of the London Underground tunnels beneath the hotel. Additionally, back-propping was required of the hotel's courtyard slab to accommodate an80-ton mobile crane.
Another challenge was avoiding interference with ongoing permanent and demolition works at lower levels. Traditional back-propping solutions would have obstructed other permanent construction works, leading to the design of two bespoke steel brackets to support the frame. One bracket was fixed to the face of an existing reinforced concrete column head, while the other was resin-bolted to the ceiling of the transfer slab. The bespoke steel brackets eliminated the need for a cumbersome three-storey back-propping frame, significantly reducing material usage and streamlining the construction process. This innovative approach not only accelerated the project timeline but also contributed to overall cost savings.
