North London specialists Purkelly Bros found themselves in a tight squeeze in Notting Hill. NCE reports.
Contiguous piling has provided an optimum balance of economy and functionality for a challenging residential development project in west London.
A substantial basement area needed to be formed beneath the entire plot of a semi-detached villa in Notting Hill. The groundwork involved underpinning the house and at the same time installing a total run of 70m of contiguous piling to the plot boundaries of the front garden, side passage and rear garden.
North London foundations specialist Purkelly Bros, who designed and installed the contiguous piling, was faced with a restricted urban site and could only access the rear garden through a narrow side passage, which itself required piling.
The alternative to contiguous piling would have been to dig out the site in sections and form reinforced walling
The alternative to contiguous piling would have been to dig out the site in sections and form reinforced walling, all of which would have involved more expense and time.
The piles at the side passage and the rear boundary of the plot had to be designed to withstand the surcharge load from adjacent properties on, or close to, the boundaries. The side boundaries in the rear garden were flanked by adjoining gardens and so retained lesser loads.
Purkelly’s solution involved 156, 300mm heavily reinforced contiguous piles set at 450mm centres, between 6m and 10m long, depending on the local load requirement at each point.
Contiguous piling is known as an effective and economical retaining wall solution for large commercial developments where there is usually better access and space for large equipment to operate in. But Purkelly’s investment in specialist mini piling rigs, coupled with developing practices geared to working in restricted residential environments, allows clients to specify contiguous piling to form retaining walls for underground developments.