FAÇADE RETENTION IN CITY-CENTRE DEVELOPMENT A presentation by Clifford Devlin

Façade retention The design and installation of façade retention schemes are increasingly being used as a means of providing modern accommodation for commercial and industrial buildings whilst preserving the external architectural features of historic and attractive buildings in conservation areas and city centres. The age and architectural significance of many of the buildings involved in city-centre projects require complex enabling work.

Clifford Devlin Limited We therefore have considerable experience of designing and installing façade retention schemes and project managing the entire process to integrate into the enabling phase. As a specialist in complex city-centre demolition we have delivered a number of projects involving listed buildings where some or all of the external elevations needed to be retained to conserve the historical character and continuity of the area.

The Process 1 Design & Approval Working from architects plans and site inspections our structural engineer will design and document the façade retention scheme. This will consist of technical drawings, load calculations, material specifications, and other data which is submitted to the client’s engineering team. A detailed condition survey is carried out prior to installation to record any existing defects which are integrated into the final project plan.

The Process 1 Design & Approval For large or complex projects we typically prepare a 3D schematic animation based on photography and architects drawings to illustrate the deconstruction methodology to the project team..

The Process 3 Fabrication As much of the structure as possible is fabricated off-site to reduce installation time on-site and minimise disruption to the busy city-centre environment. If piled foundations are required these will be installed and the pile caps constructed concurrently.

The Process 4 Installation The main towers will be transported to site on low loaders which will usually involve road closures – we have extensive experience of preparing an submitting traffic management plans to TfL and City of Westminster.

The Process 4 Installation The structures are lifted into place using a mobile or tower crane.

The Process 4 Installation The main towers are connected using waling beams and clamped to the retained structure by connecting it to an inner waling beam with tie rods. The installation is fully tested and inspected by the client’s engineers before demolition commences.

The Process 5 Monitoring We will inspect and monitor the integrity of the façade structure throughout the demolition and build phases by mapping a series of fixed points on the structure using laser range finding equipment. Monitoring will be carried out typically on a weekly basis and graphs of movement prepared and compared against agreed limits.

Our team We work with a number of trusted specialist façade retention partners who are employed by Clifford Devlin under our project management. Structural Engineers Lucking & Clark (over ten years, 10 project some temp works schemes Michael Barclay Partnership (5 years, 6 projects) Steel fabricators/installers Apex Steelworks (Crown House, Store Street) Graham Wood Structural (Tottenham Court Road)

Project portfolio Crown House (Aldwych) A ten-storey building in the heart of Theatreland was developed into an upgraded mixed-use development. Three of its existing listed stone elevations on Aldwych, Kingsway and Drury Lane needed to be retained. We designed a 60 metre eight storey retention system to support the listed façade throughout the works which took eight weeks to fabricate and erect. Value: £2.8m Duration: 10 months Architect: Sidell Gibson Principal Contractor: ISG Developer: UK and European Investments

Project portfolio Crown House (Aldwych) The structure was supported on piled foundations due to the existence of a large diameter service tunnel associated with the former Victorian tram link. We liaised extensively with Westminster Council to obtain permission for temporary road closures, traffic diversions and closure of footpaths to enable the structure to be delivered/erected. Value: £2.8m Duration: 10 months Architect: Sidell Gibson Principal Contractor: ISG Developer: UK and European Investments

Project portfolio 227-233 Tottenham Court Road A former grand retail and office building dating back to end of the 19th Century needed to be demolished to redevelop the site into a prestigious retail and office complex. Being located in a ‘conservation area, the buildings extensive ornate’ terracotta façade was to be retained. A scheme was developed, where the façade was supported using a combination of part external temporary steel support and by installing the new steel frame within the structure, with modifications to support the structure in the temporary case during demolition. Value: £2.7m Duration: 8 months Principal Contractor: Costain

Project portfolio 227-233 Tottenham Court Road This ensured the busy thoroughfare of Tottenham Court Road was not restricted by a heavy structural support and a substantial part of the new foundations and structural steel work were installed concurrently with the demolition works. Value: £2.7m Duration: 8 months Principal Contractor: Costain

Project portfolio Barrett Street, London W1 The redevelopment of the flag ship store and administrative headquarters of clothing chain Reiss’ located in a street adjoining Oxford Street required the demolition of existing buildings on the site which had been occupied by the London School of Fashion. The original brick façade at the Picton Place side was to remain and therefore required a façade retention structure was installed to provide lateral support to the façade during the demolition and construction process. Duration: 7 months Value: £1.1m Architect: Squire & Partners Project Managers: Buro 4

Project portfolio Barrett Street, London W1 Various temporary support structures to retaining walls were required due to extensive groundworks that were carried-out to the foundations. Temporary supports were provided to the adjacent buildings to serve as protection during the construction process. Duration: 7 months Value: £1.1m Architect: Squire & Partners Project Managers: Buro 4

FAÇADE RETENTION IN CITY-CENTRE DEVELOPMENT A presentation by Clifford Devlin