22 Grosvenor Square


In 2018 CDS were appointed  to design the above lower ground floor temporary works to support the existing floors of the five-storey prestige building in the heart of London, together with the restraint of the existing party walls and part of the façade wall.

The development included the demolition of the rear half area of the existing building. This left the rear party walls requiring temporary restraint and the remaining front slab area requiring temporary propping at the demolition line. In addition, part of the existing façade at the side of the building also needed to be restrained together with adjoining party wall.

As the contractor chose to proceed with the work in both the upper levels and the new basement, it was decided the LGF would be constructed ‘top-down’. The upper slabs were supported continuously down to LGF along the intended demolition line on temporary piles. These also provided temporary support to the ‘top-down’ slab. Two significant spine walls were retained at the front of the building and were used for the restraint of the rear party wall with the use of a system of flying shores and walers. No significant movement was observed during the whole of the construction period.