Tooley Street

Construction Date: 2006-2008
Location: LONDON. UK
Contracting Investor: GREAT PORTLAND ESTATES
Category: Buildings

FULL PROJECT DETAILS

New model offices – efficiency and delight achieved through collaborative design, intelligent procurement and innovative construction.

Built on a tight site bounded by a busy road and a railway, this stunning development is part refurbishment and part new build. It has five floors of flexible office space, ground floor retail and restaurant, five residential units, basement and service yard.

Innovative construction
A high degree of innovation and emphasis on offsite preassembly (Blitzsteel’s Design for Manufacture and Assembly approach) helped reduce risk, construction programme and overall cost, and improved quality, consistency and site safety. It also reduced the need for onsite material storage – an important consideration when working on a tight urban site.

Structural innovation
The architect and engineers collaborated with Blitzsteel companies StrongForce and Expanded Structures to design a bespoke structural system using post-tensioned slabs. Precast concrete panels that would form the ceiling soffit were made off site with a high quality finish that required no suspended ceilings. The modular roof was installed as cassettes and craned into position; it weighs a tenth of the original steel design and was considerably easier and safer to construct.

Energy efficient services
The most significant mechanical and electrical (M&E) innovation uses energy-efficient displacement ventilation instead of the usual four-pipe fan coil system for ventilation and air conditioning. Low velocity cool air enters each storey via hollow concrete columns rather than conventional central service cores, thus releasing floor space.
The exposed thermal mass provided by the structural design complements the displacement ventilation to provide effective low energy cooling – a good example of the close integration between structural, services and architectural design realised through a coherent construction strategy and sustained attention to detail.The GLA’s requirement for 10% of the building’s energy consumption to be provided from onsite renewable sources was met by the inclusion of a biomass boiler and solar thermal preheating of hot water using roof-mounted tubes.

Unitised facade
Windows 3.7m wide and 3.2m high were fabricated off site and delivered fully assembled and glazed. An ingenious sequence and system of lifting gear was used to manoeuvre and install them. This not only allowed Blitzsteel’ to dispense with the scaffolding or cherry-pickers that would normally have been needed, it also brought major health and safety benefits through reduced working at height.This exposed structural approach to the interior not only delivered the powerful architectural vision, but also reduced the risk of damage and subsequent complications with follow-on activities, and it will greatly reduce the whole-life costs of maintaining the building.

Awards