St Giles looks to next stage of building sustainability
Central St Giles, a former Ministry of Defence building near Tottenham Court Road and New Oxford Street, London has undergone a complete transformation to become an exemplar for sustainable and holistic development.
It has four levels of landscaped green and brown roofs. Some 60% of the rainwater is collected and reused for irrigation and toilet flushing. There are biomass boilers to provide 80% of the heat requirements. All the cooling tower water ends up being used for toilet flushing. The majority (90%) of demolition materials from its renovation were recycled, and 15% of the materials used in any new construction were from recycled sources.
Designed by Renzo Piano, the 400,000sqft development is recognisable by its multi-coloured citrus façades - covered in 134,000 glazed tiles in shades of green, orange, lime and yellow, the building is designed to offer an "efficient thermal façade".
The site is now home to companies such as WPP, Google and NBCUniversal, and the development features nine retail units on the ground level with restaurants including Jamie's Italian, Peyton & Byrne and Zizzi. In a separate building, there are 109 apartments, offering a mix of private and social housing.
As a project, the building has provided "fascinating insights" into how sustainability plays a key part in design, says Simon Wilkes, head of business space development at Legal & General, which owns the land.
"The MoD wanted to reduce its property footprint and so L&GP went through planning in 2005/06 and obtained 'vacant possession by negotiation' early to bring forward the scheme. At the planning stage, the land was owned by L&G. Once planning was approved, we looked for a partner and Mitsubishi Estates came in."
The planning stipulation strictly put sustainability measures at the forefront of design, which led L&G to employ engineers Arup and have the site managed by Broadgate Estates.
The sustainability features have helped the developer attract the tenants they were hoping for, explains Arup senior engineer David McAllister. "The building was a speculative office development so the developer's main interest was in achieving a good quality building that would meet the expectations of the type of tenant they wanted to attract, at good value. Quality and reliability were important and low energy was a consideration for BREEAM [standards] and for marketing reasons" and because low energy is the right way to go, he adds.
There are a number of different sustainability features in place but Wilkes feels that the next stage - occupation - is just as important in terms of sustainability. It's why he has commissioned a post-occupancy survey from Arup that is due next summer. This is looking at the areas of energy consumption, water consumption and current recycling rates, Wilkes says.
"Central St Giles is a very sophisticated building with over 400 electricity meters. Now that the two buildings are almost completely occupied, it is the right time to be reporting on how well the scheme is performing, and where we can make sustainability improvements."
There is also an Environmental Working Group, chaired by Broadgate Estates, which involves every tenant and feeds into their CSR and sustainability agendas. They meet formally once a quarter and, informally, monthly. All the data due back will inform future decision-making, adds Wilkes. Watch this (rather large) space for more.