Environmental sustainability has many facets, but the variety on show in Britain's greenest building, the multi-award winning Enterprise Centre (TEC) in Norfolk, is impressive indeed.
*Since going to press, it was announced that TEC was the overall winner at this year's BCO Awards ceremony.
13 October 2016
As home of one of the longest established schools of environmental science in Europe, it shouldn't be a surprise that Norwich's University of East Anglia (UEA) has seen the building of a series of low carbon buildings in recent years.
The Elizabeth Fry Building in 1995, the ZICER Building (2003), The Thomas Paine and Julian study centres (2009 and 2013 respectively) and Crome Court student accommodation (2014) are all good examples. Also, in 1997 the UEA introduced combined heat and power suppling a district heating system, while in 2006 it established a district cooling system.
However, none of these projects has received as much acclaim as its multi-award winning Enterprise Centre (TEC). it was opened last year by UEA's Adapt Low Carbon Group, a provider of environmental consultancy and investment funding.
"The Enterprise Centre is part of a long legacy of sustainable and innovative construction on the campus," explains Professor John French, CEO of the Adapt Low Carbon Group. "It has its roots in the InCrops project, an initiative to develop innovative uses for food crops."
And indeed, the TEC is a stunning example of the use of locally sourced natural materials; bio-materials make up 70 per cent of the building fabric.
All of the Adapt Group's services are delivered from the TEC, whch forms the region's green business hub alongside academia. £6 million of European Regional Development Fund grant supported the building project, alongside funds from UEA, BRE, BBSRC and the New Anglia LEP.
Construction choices
The building design team used a 'single point of delivery' (SPD) form of contract, based on the New Engineering Contract 3 (NEC3), for all work stages. Building Information Modelling (BIM) was used to support BSRIA's Soft Landings framework, which will continue for three years after opening. Specialist software model the 100 year carbon footprint of the building.
Built on a concrete raft foundation with 70 per cent cement replacement (with blast furnace slag), and with high levels of recycled steel reinforcement and sand content, embodied carbon is thus significantly lower than standard concrete. It sits over ISOQUICK polystyrene insulation, on top of recycled crushed rubble from a nearby old hospital.
To avoid floor coverings, with their high embodied carbon and frequent replacement cycles, the concrete raft's internal floor surface was ground and polished, whle glulam (glue laminated) timber provides the frame of the structure with wood brise soleil and Corsican Pine for internal walls, much of it sourced from Norfolk forests. Suffolk thatch provides the roofing and, in a world first, pre-thatched Norfolk Long Straw in vertical cassettes is used for wall cladding. Windows are triple-glazed and airtightness is rated at 100 times better than the requirement in Building Regulations Part L. Although Passivhaus certified, the building does benefit from slender windows that may be opened for ventilation.
The aim was to provide a building that would use no more than 500kg of carbon dioxide per square metre (sqm) in both building and operation over 100 years. The figure actually achieved? 441kg/m2.
Engineering choices
Entrance air locks, a large roof top, windows for night purging and high levels of heat recovery using thermal wheels are all automatically managed to provide the correct air temperature and quality levels within the building.
In each room, LED panels indicate to occpants when optimum temperatures will allow people to open or close windows. In the summer months, these panels also indicate when the windows can be left open to aid night cooling.
With such high levels of airtightness, only three air handling units (AHUs) are needed, providing fresh and filtered air to every room, controlled by Variable Air Volume (VAV) units in a serviced bulkhead. The BMS controls light levels via room monitors and exhaled CO2 levels via the VAV motor and dampers. (Only the 300 seat lecture theatre has need of a traditional cooling system, for maintenance of comfortable conditions in the summer months.)
The TEC draws from UEA's district heating system, while the design team found that less energy would be used in the south wing through the deployment of point-of-use electric water heaters to avoid high standing heat losses in lengthy supply pipes. A 480 sqm photovoltaic array on the roof provides much of the base electrical supply, with some exported to the UEA's district electrical systems.
The audio-visual system was chosen for its low in-use demands and connectivity to remote controlled power on/off routines, while the 3.3m-high ceilings provide enough volume to cope with temperature and quality fluctuations as well as daylight, which intelligently-controlled LED lighting augments when necessary.
The specific prime energy demand of a Passivhaus building must not exceed 120 kWh per sqm annually; post occupancy evaluation for the first year of operation indicates that the building is coming significantly below this threshold, at 103kwh per sqm annually.
The Norwich Research Park, of which the TEC is a centrepiece, is a partnership between UEA, the Norfolk and Norwich University Hospital and four independent world-class research institutes: the John Innes Centre, the Institute of Food Research and The Genome Analysis Centre (all strategically funded by the Biotechnology and Biological Sciences Research Council (BBSRC)) and The Sainsbury Laboratory linked to the Gatsby Charitable Foundation. The BBSRC is itself a partner, as is the John Innes Foundation.
More than 11,000 people work across the site, including 2,700 scientists with an annual research spend of over £100 million.
"In the North Wing, we offer a range of tenancies", explains Angela Macdonald, tenancy and business development manager, "from virtual through to hot-desking and co-working to complete office suites." As well as a lecture theatre and foyers for exhibition space, meeting and seminar rooms cater for up to 40 people.
The TEC achieved the Passivhaus standard and a BREEAM outstanding rating of 93 per cent - it's the combination of both these measures that makes it, in the UEA's eyes, Britain's greenest building.
