Walsh Group

The development at Baker Street consisted of a 9 storey RC framed building over a 2 storey basement and consists of commercial units on the ground floor and private residential units above. Adjacent to this is a 3 storey RC flat slab framed building which provides affordable housing. The site was the home of the old Abbey National building head quarters which was demolished but the clock tower above the building was retained.

The main part of the project was driven by 2 factors, 1). the new building had to provide the same overall loading as the previous building which was demolished as additional load could not be added to the tube lines beneath the site and
2). the new building had to be constructed around and resupport the existing clocktower and façades temporary work supports.

The foundation for the private block was a 750mm to 825mm RC raft over existing foundations.
Sections of the existing basement walls were reused and integrated with the new extended basement. At ground floor there is a 750mm transfer slab so that the columns to the car park could be accommodated below. There is also a 1325mm deep transfer beam under the façade at ground floor to support its steelwork stanchions.

The clock tower was lifted from the existing steelwork stanchions using flat jacks and resupported on the new RC frame with a 450mm transfer slab as the main supporting member.

By using lots of perimeter wall supports as the building sets back above large transfer structures were avoided.

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