With the government’s plan to cut carbon emission by 80% by 2050, energy efficiency will have to increase across all sectors, including retail. In the case of Tesco’s new stores in Corby, Northamptonshire, and Newmarket, Suffolk, sustainability is high on the agenda, with both building projects achieving a BREEAM Very Good rating, earning them the designation of ‘Eco Stores’.
Bedford-based architects Engineers and Development Consultants Woods Hardwick designed the stores to deliver against three criteria. Firstly, to ensure that the retail store was fitted out in a sustainable way, in terms of working practice and of material choices. Secondly the building had to be as energy-efficient as possible, and finally the project was expected to use renewable and low-carbon technologies where practicable. These aims were driven by statutory requirements and Tesco’s own stringent environmental criteria.
Timber played an important role in the design of the stores, as timber is one of the most efficient, safest and cheapest forms of carbon capture and storage available to architects and engineers as a building material, making it an ideal solution for the increasingly eco-conscious retail industry. Wherever possible a timber frame and a sustainable timber cladding system was proposed to reduce embedded carbon by 20-25 per cent.
Design features work in conjunction with the low-carbon and renewable options to deliver a total reduction in carbon emissions of up to 70 per cent compared with a like-sized standard store in 2006.
Both stores incorporate sustainable material choices and energy efficient elements. These include a combined heat and power unit, a draught lobby to reduce heat loss, rainwater harvesting, improved service metering and CO2 refrigeration to reduce carbon emissions.
The single-storey supermarkets are clad in a combination of curtain walling and timber structural insulated panels (SIPs) faced in a larch outer rainscreen. Larch was specified for its durability and low maintenance characteristics, making it a long-term cost effective cladding solution.
The supermarkets were designed to cope thermally with the additional demand placed on buildings of this size and function. The overall thermal performance of the external wall was increased from that of previous trial stores, and SIPs were installed after being manufactured off-site.
The stores feature a mixed mode ventilation scheme, utilising roof-mounted windcatchers, and large format rooflights which deliver natural daylight deep into the sales floor. The rooflights supplement the need for artificial light and helps to prevent excess heat gain or loss.
Rainwater is collected from the roof and used to provide water for the toilets, lowering water consumption and providing sustainability and revenue benefits. Improved metering of electricity, water and gas allows the building’s users to better understand consumption and identify problems as soon as they arise.
With any eco development, there is always the danger of the build looking out of place in its surrounding environment. However, with the Newmarket and Corby Eco stores,, architects at Woods Hardwick considered the external environment, internal demands, BREEAM Benchmarks and the supermarket’s own high environmentally-conscious standards. This holistic approach will leave a lasting legacy in both environmental and building terms.
