AREA: 192,000 SQ FT



Leslie Clark was appointed to provide cost consultancy services on the refurbishment and three-storey roof-top extension of this existing office building on Aldersgate Street in The City of London. The works will comprise the complete stripping out of the existing building and alteration work to remove the upper roof and floors and all of the external cladding, curtain walling and windows. The building will be extended to the rear and an adjoining smaller building added to the overall footprint of the scheme increasing the gross internal area by over 60%.

  • Major structural alterations will take place to increase the net lettable area around the perimeter and rear elevation of the building where the new curtain walling is to be installed, together with a larger, double-height reception with new lifts and disabled access facilities. There will be smaller cores and reconfigured executive toilets on each floor. The basement slab will also be lowered to increase net area and to increase head height in certain parts of the basement for plant, cycle storage and showers and lockers.
  • The increased net area of the building will be completed to a Cat A specification with raised access flooring and new building services and finished befittng a Grade A office building. This Cat A specification will include natural ventilation to certain areas and possible use of central localised power supply from Citigen located at Farringdon. Not all floors will be completed to Cat A standard with some floors left as shell and core for the incoming tenants to fit out in their style.
  • Similarly, to our other major re-development projects, the cladding package will likely be procured ahead of the main contract with a separate tender undertaken for these works. The cladding sub-contractor will then be novated to the successful main contractor following a competitive single stage design and build contract tender process. This will enable design to be progressed with the cladding sub-contractor and the specialist prior to the main contractor being appointed.
  • The strip out will inevitably be completed prior to the appointment of the main contractor who will then utilise this incumbent demolition contractor to remove the roof, top floor and external envelope, together with all noisy structural alteration works. This will again help with the programme and allowed early sight of the existing structure which will assist the design in de-risking the project.
  • Novation of the cladding contractor will assist with the overall programme and Leslie Clark will be instrumental in the final negotiations with the successful cladding contractor and subsequently the novation to the main contractor during final negotiation of the main contract.

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Leslie Clark specialises in the retail, office/commercial, leisure/hospitality, and residential sectors but has extensive experience of many other project types throughout the UK. Today we are at the forefront of sustainability alongside many of our clients.