Savvy retailers are learning that wood has a winning aesthetic for today’s more eco-conscious consumers, and given its innate sustainable credentials it means retail therapy doesn’t have to be quite such a guilty pleasure reports Mark Cantrell
Fancy a coffee? No, of course you don’t – you’re here for the timber. But there’s a place just opened in Wrekin where you can imbibe a caffeine hit and check out some innovative timber engineering while you’re at it. Okay, you can have a cup of tea if you really must.
Anyway, cafe chain Costa, part of the Whitbread retail empire, has opened its first so-called ‘Eco Pod’ store at Wrekin Retail Park, near Telford in Shropshire. It’s a regular coffee shop as far as the retail side goes, but from a design and construction perspective, it features the kinds of innovations and energy saving technologies intended to make it a ‘zero energy’ building.
Obviously, it’s not going to be completely ‘zero’ energy – nobody wants cold coffee, right? – but passive ventilation and those construction techniques are supposed to greatly reduce the energy required for space heating and cooling. This energy requirement, so we are told, will be covered by solar photovoltaic cells embedded in the specially curved roof.
The retail park is owned by a company called Hammerson. In fact, it owns the carbon neutral Eco Pod too and leases it to Costa, but the two companies worked together to explore and develop the concept.
“This is an exciting first for coffee shop and retail design here in the UK and has the potential to transform not just how we build new stores at Costa, but the industry far more widely,” said Jim Slater, managing director of Costa UK & Ireland.
“We wanted to explore new ways to serve quality coffee to our customers while managing our environmental footprint as responsibly as we can. Through a successful partnership with Hammerson, we have developed an outstanding new type of test bed building design which really does have the potential to make a massive difference if rolled out more widely.”
Key design features include:
• A glulam timber frame constructed using FSC-sourced timber as an alternative to traditional steel frame, reducing the building’s embodied carbon footprint
• A super-insulated facade using softwood said to have excellent energy retention properties. As such, it keeps more heat in during the winter but helps keep the inside cool during the summer
• “Intelligent” orientation of the building so that it achieves optimum levels of sun and shade, which impacts on the overall energy requirements for heating and cooling
• An underfloor heating system and passive ventilation
Hammerson and Costa called in architects Emission Zero, which specialise in low carbon design, while the project was managed by Projex Building Solutions. The glulam frames were designed and made by Fordingbridge.
“The development is pioneering for retail units of this type owing to the ‘zero energy’ design and collaborative working of the supply chain to develop the project from desk top theory into reality,” said Projex. “The design principles drive a zero energy building, whereby the running costs are set off by the energy savings generated by sustainable solutions such as thermal mass heating and cooling, passive ventilation, and photovoltaic energy storage.
“By embracing the supply chain from desk top feasibility as opposed to the more conventional post-contract design and build introduction, we have generated a sustainable building with zero energy performance and understated aesthetic appeal with the potential to become market leading.”
Tom Cochrane, Hammerson’s asset manager said: “The opening of the Costa Eco Pod is a significant achievement for our team and clearly demonstrates that as a business Hammerson is at the forefront of consumer awareness of supply chain ethics and environmental impacts. By working collaboratively, we have been able to provide Costa with an entirely new and innovative concept store, as well as a UK first. Using this blueprint for low-carbon sustainable design we hope to support, where possible, other retailers in creating truly sustainable assets.”
Clearly, the partners are proud of their eco-baby and have every confidence in its capabilities. Provisionally, the Eco Pod has been given an Energy Performance Certificate rating of A+. But there’s a while to go before the building proves the eco-hype in practice; it opened early April and the plan is to monitor its performance over the next six to 12 months. The proof of the muffin is in the eating, after all.
Costa might have scored itself a PR coup with its eye-catching coffee shop, but it’s not the only retailer that is looking to make the most of timber as a natural-born building material. And there are plenty of reasons why, from the aesthetics of wood, through its structural capabilities, all the way to its environmental credentials as a means to lock away carbon emissions in the built environment.
“Wood as a building material is unique and flexible,” said Ellen Jones, architect at Bedford-based Woods Hardwick. “It has inherent aesthetic, textural and sensual qualities, and as a result can be utilised within buildings for structural purposes right through to decorative finishes. Through managed and sustainable sources we have plentiful, cost-effective and ecologically sound supply, which is preferable from historically damaging alternatives.”
The advantages of timber are many, said Jones; namely:
• The UK is a world leader in advanced engineered timber construction. Timber engineering, including SIPS, has the advantage of being manufactured off-site. Light enough to provide fast on-site assembly, it reduces build times and costs dramatically
• Buildings using timber are more textural and tactile than traditional steel-framed constructions. In Jones’s view they “feel softer and more relaxed” than steel and will therefore provide a different experience visually as well as spatially
• Timber engineered frame solutions offer “excellent” thermal, fire and acoustic properties and are able to “better resist” environmental influences and chemicals compared to structures using alternative materials
• By-products from the timber manufacturing process can be fully recycled
• Wood products such as glulam and cross-laminated timber provide “infinite” design possibilities without compromising on structural design. By being cost-effective and an “excellent ecological building material”, Jones said Woods Hardwick is able to provide its commercial clients with innovative designs that satisfy both cost requirements and environmental standards
“Looking to the future and the increasing requirements on carbon reduction to satisfy even the most basic requirements, we feel timber will have an increasing role in reaching this conjunction with low-carbon technologies. At Woods Hardwick we will continue to advocate the use of wood in our designs and communicate the many benefits it provides,” Jones added.
In Corby, Northamptonshire, the firm has applied its thinking on behalf of Tesco with the design and construction of a new so-called Eco Store and an associated petrol station. The latter inevitably invites a raised eyebrow, motorists’ collected carbon emissions considered, but the stores themselves have been constructed to minimise their impact on the environment.
The new Tesco Eco Store provides 82,565 sq ft of sales space and occupies a 7.8 hectare former brownfield site that was a leftover relic of the town’s steel working industry. This made it a challenging project, by all accounts, but in its landscaped setting, wrapped in an ‘ecology zone’, the new store was built to establish a striking presence. The single-storey supermarket is clad in a combination of curtain walling and timber structural insulated panels (SIPs) faced in a larch outer rainscreen. It has achieved a BREAAM ‘Very Good’ rating.
“This was a challenging and exacting brief to work on,” said Jones, who was lead architect on the Corby project. “Our response was driven by the complexity of the site’s heritage and the context that what was principally an out of town development was to be treated and viewed as an in-town development.”
Woods Hardwick is working to deliver another Tesco Eco Store, this one in Newmarket, Suffolk, but it is hoped to follow in the – reduced – carbon footprint of its Corby sibling and achieve BREAAM ‘Very Good’. Again, it’s a brownfield site but on this occasion it is replacing an earlier Tesco store that was opened in the 1980s.
Like its Corby counterpart, the Newmarket Eco Store resides in a landscaped setting and has an associated filling station, although this one – a single food store – is smaller at 70,000 sq ft. It will be clad in a combination of glazed curtain walling to the front elevation and timber cassette panels faced in a larch outer rainscreen to the side elevations. Inside the store, the engineered timber frame is to be left exposed. The idea is to link the “strong visual aesthetic of timber inside and out”. The frame also reduces the building’s embedded carbon by 20-25%.
The fabric complements the energy efficiency elements incorporated into the buildings: a combined heat and power unit, a draught lobby intended to reduce heat loss, rainwater harvesting, improved service metering and CO2 refrigeration to reduce carbon emissions. The store will also make use of a mixed mode ventilation scheme, making use of roof-mounted windcatchers. It will also feature large rooflights to allow natural daylight onto the sales floor. These will supplement artificial lighting and also, it is claimed, prevent excess heat loss or gain. The shell is due to be completed in August with the fit-out completed at the end of this year.
Shopping, as retail firms know all too well, is about more than the cold mechanics of assembling the building and kitting it out; it has to appeal at an almost subliminal level, creating an alluring welcoming presence, that is as much marketing art and psychology as it is science and engineering.
Wood, with its natural, almost homely aesthetic, is clearly a winning material in the retail war to win consumer hearts and minds. That it also evokes the environment and green living in this carbon conscious era is clearly the icing on the cake.
This article first appeared in the Summer 2015 print edition of Timber in Construction magazine