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Environmental auditing of building design is increasingly demanded as a component of planning. This is conducted through the Building Research Establishment's Environmental Assessment Method (BREEAM) , which is roughly equivalent to the Leadership in Energy and Environmental Design (LEED) from the U.S. Green Building Council. Public-sector procurement in the United Kingdom now requires high ratings under BREEAM or related schemes.

Generation Versus Conservation

One of the most ambitious areas of change is an emerging requirement for renewable onsite energy generation. The London Borough of Merton was the first planning authority to introduce a requirement for all new buildings to generate 10 percent of their energy requirements on site.

It has been argued that if controlling carbon emissions is the goal, energy conservation would be more cost effective than generation. Merton's counterargument is that creating a market for renewable energy is critical to its development and that their policy inherently promotes energy conservation anyway because the 10 percent target is easier to achieve if the building's predicted consumption is first reduced.

The London Borough of Croydon has now implemented a similar policy, and more planning authorities are expected to follow Merton's lead.

There have also been changes to the UK building regulations. Part L (Part J in Scotland), covering conservation of fuel and power, now addresses the energy efficiency of both the building fabric and the building services and allows one to be traded off against the other.

Dynamic computer simulation modeling can be used to establish that a building's annual energy performance meets the required standard. For example, Part L compliance for an air-conditioned office building can be achieved simply by demonstrating that the annual carbon emissions associated with heating, cooling, ventilation, and lighting do not, under standard conditions, exceed 1.2 pounds per cubic foot (18.5 kilograms per cubic meter).

This allows a very flexible, creative approach to designing energy-efficient buildings that demands a closer working relationship between architect and engineer in the early design stages.

Documenting Performance

Much of Britain's social and environmental legislation is now in response to European Union (EU) directives which, some argue, allow unpopular changes to be introduced "by the backdoor." One of the most recent examples is the EU Directive on Energy Performance of Buildings. This requires member states to introduce legislation to ensure that buildings have a current energy certificate available to prospective tenants or purchasers identifying and benchmarking performance.

The intention is to promote carbon efficiency by developing a transparent market value for it. One of its most far-reaching aspects is its coverage of existing buildings. By contrast, improvements to the nonretroactive building regulations have limited effect because only one percent of the UK building stock is replaced each year.

In addition, the Climate Change Levy on electricity and gas, Enhanced Capital Allowance (ECA) on approved energy efficiency measures, and the expansion of renewable sources of energy — to 10 percent of electricity production by 2010 — all promote environmentally responsible design.

But there is frustration at the fragmented, inconsistent, and bureaucratic nature of the government's approach to the environment — the antithesis of the integrated thinking we were promised. An appropriately rated carbon tax, for example, would give market value to energy efficiency measures, promote renewable sources, and render ECA insignificant. However, a carbon tax is considered too politically risky.

Celebrating Progress

Nonetheless, significant progress has been made in the last five years. The environment is on the agenda of almost every building project, and there is a growing acceptance that the most cost-effective approach to it is integrated design.

As a result, the role of consulting engineers in the United Kingdom, working closely with architects, is changing dramatically in scope, with engineering making a more significant contribution to the design of the building's form.

Engineering input might be in facade design or in site planning — in modeling sunlight, daylight, and wind microclimates around buildings, for instance. This holistic, symbiotic approach can add considerable value to a project, particularly in a restrictive planning environment as in the United Kingdom, but also in less regulated countries like the United States.

The main resistance to this design approach is from developers and clients who see "front-loaded" fees — higher expenditure before receiving planning permission — as a business risk.

While some architects are perhaps concerned about losing control over conceptual design, environmental issues should, in my view, simply be considered a design driver equal to but not dominant over, say, structure or aesthetics. A good engineer should define the key environmental issues at an early stage, so they can become part of the design criteria and contribute to creating solutions.

I have heard it said that while Britain is a decade behind Europe environmentally, North America is a decade behind Britain. If true, this indicates that building design in the United States could be transformed dramatically over the next ten years. Although federal leadership is currently lacking, there's hope that positive steps — targets for renewable sources of energy — can be taken at state and local levels.

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Ross French is an associate at the London office of Rybka, an international building services consultancy. Rybka offers a range of environmental services, including concept design, environmental impact assessment, benchmarking, and post-completion monitoring, as well as traditional mechanical and electrical engineering.

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