The revisions to the regulations, which are expected to include demands that walls, floors, roofs and windows are better insulated, will have a profound impact on how buildings are designed and constructed. Construction minister Nick Raynsford is driving through the changes to help fulfil the government’s manifesto commitment to reduce carbon dioxide emissions by 20% before 2010, and thereby slow global warming. Launching the government’s new sustainability strategy earlier this month, Raynsford said he wants to create “a more socially and environmentally responsible, better-regarded construction industry”. Buildings account for over half of UK energy consumption, of which 60% is attributable to space heating.
However, some of the changes to Part L are likely to be opposed by housebuilders who have argued that, from an energy-efficiency point of view, it would be better to concentrate on the performance of domestic appliances than increasing insulation standards.
Speaking at the Building Energy Efficiency conference, which took place in Solihull on 11 April, Irving would not give a precise timescale for the full implementation of the changes, although industry sources suggest that some of the most controversial aspects – such as making the rules apply to existing, as well as new, buildings – will be delayed until 2009 or 2010.
However, Irving said the changes need to start now if the government is to meet its commitment and the Kyoto Summit target of reducing emissions of six gases by 2012. “It’s a bit like reversing a supertanker,” he told the 170-strong audience at the conference, which was organised by the British Rigid Urethane Foam Manufacturers’ Association in association with Building. But he warned that change was essential. ”We have to make sure we effectively implement these proposals to advance a more sustainable future for the construction industry.”
The DETR is expected to publish its proposed changes to Part L in May. Irving briefly flashed up a slide confirming figures revealed in Building last month that increases in thermal efficiency requirements will be phased in between 2001 and 2003. For example, the U-value for walls will change from 0.45 W/m2°C to 0.35 W/m2°C next year, and then drop to 0.3 W/m2°C two years later. The requirement for windows will change from 3.3 to 2.2 in 2001, and then to 2.0 in 2003. Many in the industry will welcome the phased approach, which is designed, as Irving said, “to achieve the robustness we are after”. But housebuilders are understood to be concerned that, given the lengthy delays in the planning system, they might be forced to work with three different sets of regulations. Irving’s suggestion that housebuilders will not be allowed “unlimited trade-off” between insulation and the efficiency of heating systems is likely to be equally unpopular.
Few would argue, however, with the new Part L’s expected requirement for performance testing, to ensure that designs to high standards of energy efficiency are delivered on site. Architect Stuart Borland, a building envelope specialist, told the conference that surveys carried out by his company, Building Sciences, show that the vast majority of buildings do not even comply with the current minimum thermal design standards, largely because of poor construction.
Borland pointed out that insulation must be installed in a continuous layer. However, thermographic surveys show that many buildings have significant gaps. In a typical industrial unit constructed with a standard site-assembled cladding system, it has been estimated that 6% of the insulation may be missing, which is responsible for increasing heat loss 33%.
Borland said: “If we are to be realistic about reducing energy consumption in new buildings, increasing the regulatory standards must be just the beginning. The real challenge will be in ensuring that what is built actually achieves the theoretical design parameters … The mass UK construction industry requires a very significant change in attitude and work principles.”
Other speakers at the conference, chaired by Building editor Adrian Barrick, highlighted the range of regulatory devices and best practice guidance that are helping to steer construction towards a more sustainable future. Paul Ashford, co-chair of the United Nations’ environmental programme technical options committee, said the government’s enhanced capital allowances to encourage companies to improve their buildings’ energy efficiency were significant because “they put the issue in front of finance directors”.
Tim Curtis, head of programmes at the Energy Savings Trust, outlined a number of initiatives that his organisation is undertaking to improve energy efficiency in the domestic sector. These include the New Home Energy Efficiency Scheme, which is to be relaunched in June and which provides – among other things – cheap insulation for poor families to help cut their heating bills. “Very simple things can make a big difference,” he said. “There is a lot that can be done at a very low cost.”
Similarly, in the commercial sector, Paul Davidson, director of BRECSU at BRE, stressed the economic benefits of energy efficiency. “Wasting energy wastes money,” he said. As director of the buildings part of the government’s energy efficiency best-practice programme, he has helped to cut CO2 emissions by 1.6 million tonnes a year.
He urged all businesses to take their responsibilities for energy management seriously and, in commissioning new buildings, to think carefully about the impact of the location, orientation and layout, to use heating more efficiently and to optimise lighting. Energy-saving devices have already cut £400m from fuel bills across all building types nationally, but if government targets are to be met, there needs to be more long-term planning. “You have to do something now to achieve an effect even 20 years down the line,” Davidson warned.
Architect John Potter, giving an industry professional’s view, laid much of the blame for the poor standards of energy efficiency on mass housebuilders. “They have a lot to answer for,” he said. Recalling a phrase coined by former RIBA president Alex Gordon nearly 30 years ago, he said: “We should build bigger homes, looser fit, for longer life, and more energy-efficient. We must have a revolution in our thinking.”