USERS DO NOT ALWAYS MAXIMISE DESIGN ASPIRATIONS
New research, to be presented at the BCO conference in New York on 2 May, shows that it is often not a lack of innovation which stands in the way of reduced carbon emissions in office buildings, but a lack of occupier feedback and little involvement from the architect after occupation.
New research by the British Council for Offices (BCO) with Arup shows that the biggest obstacle in reducing carbon emissions in office buildings is the process by which these buildings are briefed, designed and operated, rather than lack of 'technical' innovation.
The research focuses on how to gain detailed feedback from occupiers that can be incorporated into the briefing and design stages of building in order to create buildings that are intrinsically frugal in their energy consumption. The BCO's environmental sustainability group and technical affairs committee will release these findings at the BCO annual conference on 2-4 May in New York, in an interim report entitled 'Towards a Zero-Carbon Office'.
Research by one of the UK's largest office providers, Land Securities, showed that energy use in its buildings could be cut by as much as 40 per cent simply by working with sustainability teams and occupiers to manage consumption more effectively.
There is often a gap between the design aspirations of buildings and the ability of occupiers to maximise a building's capability to reduce carbon emissions. This may be because a designer's involvement with a building usually ends on completion and does not extend to occupation. 'Towards a Zero-Carbon Office' is about strengthening links in the process of briefing, designing and building to ensure that when a building is occupied it delivers a low-carbon future.
Although architects help to formulate the brief for a building it is rare for an architect to be involved in the handover to an occupier and the use of the building, despite the important part that they could play in bringing the building to its full potential.
The BCO is looking at how to generate better 'postoccupancy evaluation and feedback', perhaps building on the PROBE research that building-services engineers have been using for some time. Many well-meaning design ideas are greeted enthusiastically, but an idea used ineffectively can be worse than nothing at all. This is one of the weakest links in the chain.
It is imperative that the industry tackles this problem, particularly since implementation of the new European Directive on the Energy Performance of Buildings is due within the next two months. Some property companies are already commissioning assessments of their buildings on the basis of the directive's requirements. The directive is designed to establish comparative grades for use in the market to discriminate between buildings on the basis of their environmental performance, and will require a building's energy performance to be specified when it is let or sold.
The top band of performance will require carbon emissions to be 60 per cent below those permitted by the regulations.
The EU directive is seen as perhaps the first step towards establishing a basis on which buildings can be taxed according to their energy performance - a chilling prospect for developers, investors and designers. The architect's role in meeting this challenge has never been more important and cannot be delegated to the environmental engineer because of the user's involvement in optimising performance and engaging with the building. A design solution must be holistic, resolving issues 'upstream' and 'downstream' from the design and building parts of the process.
It is no longer enough to simply consider the improvement in the energy performance of office buildings as a series of 'green' features. The crux of the matter lies in modifying client and design team behaviour during the briefing, design and occupation process.
It is essential that architects enhance their leadership role in this area. The following two case studies demonstrate this.
ARUP CAMPUS, SOLIHULL Arup's own 10,000m 2 regional office campus at the Blythe Valley Office Park in Solihull, designed by Arup Associates and first occupied five years ago, demonstrates the sort of benefits that can be achieved using occupier feedback. A third party, Building Use Studies, was employed to investigate the two buildings and to interview their occupants, asking them specifically about comfort.
The buildings are deep-plan, high-performance, naturally ventilated offices. The depth of the plan meant that heating and cooling was always going to be problematic without airconditioning. Localised drafts, it transpired, were a problem. They were caused by the outside air inlet, which has now been evolved to include a heater battery that heats incoming air automatically to offset the draft - a change that significantly improves the experience of the natural ventilation for occupants.
ROPEMAKER PLACE, CITY OF LONDON
The role of technology in reducing carbon emissions must be tested each time. Ropemaker Place in the City of London is a 46,500m 2 British Land office development by Arup Associates which has been granted planning permission. A Combined Heat and Power (CHP) system with an additional cooling cycle for chilling was considered for Ropemaker Place because of its size, but was rejected after detailed analysis.
Gas-fired CHP systems, particularly with an additional cooling cycle, do not necessarily reduce a project's carbon footprint. Projections for Ropemaker Place forecast increased energy consumption with a CHP system when compared to conventional power supplies, because low-energy features incorporated in the design, such as solar water heating, meant very little heat from the CHP system was actually needed. And where cooling was required, the conversion process driven by excess heat in a CHP system, when compared to efficient modern electrical chillers connected to mains power, was much less efficient.
Mike Beaven is a principal of Arup Associates and chair of the BCO's Environmental Sustainability Group. The BCO would like to hear any feedback or experience AJ readers may have on these matters. Please email Ian Selby on mail@bco. org. uk.
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