Aug 26, 2013
The First Priority of Low Cost Sustainable Building
In July the UK Government announced its changes to Part L of the Building Regulations. These revisions mean construction companies will be required deliver a higher level of energy efficiency in all new builds as of April next year.
To be precise, the revised targets require a six per cent reduction in carbon emissions for residential buildings, and a nine per cent reduction for all non-domestic buildings.
The market has only recently begun to show signs of renewed activity following the impact of the UK recession. This has led many to suggest that potential cost implications associated with energy efficient technologies, often relied upon to meet sustainability targets, could have a negative impact on the wider recovery.
However, one advantage of the recession is that it has encouraged the market to look at alternative, more innovative methods of construction. We place significant emphasis on R&D investment to develop not just energy and cost efficient products, but also ensure that they are used in the most energy and cost efficient manner.
One of the most effective ways to maximise energy efficiency and control build costs is to adopt a fabric first approach. This means incorporating energy efficiency into the build envelope and reducing the dependency on often expensive technology ‘bolt-ons’, thus keeping costs down.
Timber has the lowest embodied carbon of any commercially available material and can deliver an overall energy reduction of up to 33 per cent. However, fabric first is not just about the material used, but the way in which it is used. Energy efficient buildings have three key dynamics that must be approached in the right way to get the best results: U-values, air tightness, and thermal bridging. Our R&D focus has enabled us to develop products with U-values as low as 0.10, air tightness down to 1.5, and thermal bridging of only 0.02. As an example, our Sigma OP external wall system has helped customers achieve up to level 5 in the Codes for Sustainable Homes. Similarly our BBA certified Sigma II Build System, which can now support up to six storeys, achieves excellent air tightness and has won a number of industry awards for its superior performance and cost effectiveness.
A residual benefit of fabric first is its ‘fit and forget’ quality. With the shifting focus towards energy performance, it’s crucial that homes are easy to run and maintain, making saving energy easy. Incorporating energy efficiency into the build envelope reduces the dependency on end consumers changing their behaviour or adapting to new technologies in order to achieve performance standards. A fabric first approach means the building will continue to achieve high standards of energy efficiency whether the inhabitant elects to use energy efficient devices or not.
Finally a fabric first approach centred on, for example, a timber build system such as the Sigma II Build System can bring about additional cost savings and increase speed of build. Owing to the offsite manufacturing process, time on site is greatly reduced which brings about a reduction in labour costs. Equally, because the entire system can be designed, manufactured, and erected on site in a matter of weeks, return on investment is realised sooner and cash flow is better protected.
The industry is under pressure to deliver improved energy efficiency and, with the market still fragile following the effects of the recession, it’s important we continue to develop new products and methods by which to achieve governmental targets. Focusing on the building material as a first priority rather than solely relying on potentially expensive energy saving technology – which may or may not be adopted by the end user – can help deliver high energy performance while keeping costs down.