The retrofit of 5 New Street Square for Landsec, designed by Bennetts Associates, has completed. Transforming the central London office building into a high-performing, contemporary workplace that demonstrates how the retrofit of commercial buildings can deliver low-carbon retrofit and improved occupant wellbeing.
Originally designed by Bennetts Associates in 2008 as part of the wider New Street Square masterplan in the City of London, the transformation has upgraded the building with a strong focus on retaining and enhancing existing elements to minimise upfront carbon.
A detailed net zero carbon roadmap was developed and modelled to establish the most effective interventions for meeting operational energy intensity targets. This prioritised centralised plant renewal and a transition to all-electric systems, with the project on track for a NABERS 4.5-star rating.
Significant operational energy savings have been delivered through a partial mixed-mode operation using refurbished façade vents for natural ventilation in spring and autumn.
Circular economy principles were also central to the design, with extensive reuse of the raised access floors, existing riser ductwork, main electrical infrastructure and pipework. Refurbishment of air handling plant and secondary pump sets has further minimised upfront carbon, while sustainable new materials – including bamboo cubicles – were specified where replacement was required.
Alongside the technical upgrades, the building’s reception, lounge areas and washrooms have been refurbished. Roof terraces have been revitalised with new planting and common areas redesigned to enhance user wellbeing.
Rob Bearyman, Director at Bennetts Associates, said:
“Our approach at 5 New Street Square demonstrates how deep retrofit can balance operational and upfront carbon while enhancing the experience of those who use the building every day. By retaining the existing façade and focusing investment on systems renewal and wellbeing, we’ve shown that buildings of this generation can be adapted to meet today’s resource consciousness and social value ambitions without unnecessary waste.”
5 New Street Square underlines Bennetts Associates’ continued commitment to delivering practical, future-ready solutions that support the transition to net zero.