Until recently, building contractors had neither a strong incentive nor a reliable mechanism to introduce sustainable practices. But there are signs of change. The Building Research Establishment’s Environmental Assessment Method (BREEAM) is leading the way to provide a suitable set of standards to ensure that the environmental costs of a building may be measured and accounted for throughout its entire life cycle. Recent commitments by government and large building contractors indicate that application of BREEAM will expand rapidly in the next few years. This is a tremendous opportunity to increase the use of timber in UK construction.
The government announced in its sustainability action plan “Achieving Sustainability in Construction Procurement” that from March 2003 all government procured projects must achieve a BREEAM or equivalent rating of “Excellent” for new build and “Very good” for refurbishments. Given that the UK government is by far the largest single customer of the construction sector, estimated to account for around 40% of total UK construction activity, the implications are profound.
And already more private sector clients are stating a BREEAM rating as a design request at tender stage, encouraged partly by the knock-on benefits of strong environmental performance in promoting improved energy efficiency and therefore economic performance, and improved relations with local communities and planning authorities.
A review of the new EcoHomes 2006 standard, released in April, suggests it should provide a tremendous boost for timber. The standard assesses the environmental performance of a building across eight impact categories: Energy; Transport; Pollution; Materials; Water; Land Use and Ecology; Health and Well-being; and Management. Credits are allocated for good environmental performance, with a total of 107 credits available across all categories. However, a weighting factor is applied to each category to give an overall score out of 100. One complication is that each credit is not worth an equal amount, varying between 0.48% (Materials) and 2.14% (Pollution). The weighting applied to each category varies from year to year as the significance of different impacts will change (for example energy efficiency is now a high priority). The overall score dictates a rating of Pass (over 36 points), Good (over 48), Very Good (over 58) or Excellent (over 70).
Increased use of wood contributes indirectly to achievement of extra points in the Energy category, which focuses mainly on carbon dioxide emissions during operation of the home; and in the Health and Well Being category, where sound insulation is referenced.
However, the direct benefits from increased use of wood really pile up under the Materials category. A total of 31 credits are available under this category, 16 of which are allocated “to encourage the use of materials that have less impact on the environment taking account of the full life cycle”. To achieve these credits, the various building elements (roof, ground floor, frame, upper floors, walls) must achieve an A rating in the Green Guide for Housing Specification. Wood-based elements regularly achieve an A rating in this guide which is based on BRE’s own extensive environmental database.
A further nine credits under the Materials category are allocated for “Responsible Sourcing”. Inevitably this section has been the subject of most comment in the timber sector due to BRE’s allocation of variable points to different forest certification brands. EcoHomes separates certification schemes into four tiers. Forest Stewardship Council (FSC), Canadian Standards Association (CSA) and Sustainable Forestry Initiative (SFI) (with chain of custody) are in tier 1 and score the maximum three points per building element. PEFC is in the second tier scoring two points. The third tier, scoring 1.5 points, is for suppliers of non-wood products that have achieved ISO 14001 or EMAS at the extraction and process stage. The fourth tier, scoring one point, is for wood products certified to the Malaysian Timber Certification Council scheme, Timbmet’s “Verified” system for legal verification, or an SGS or Tropical Forest Trust chain of custody system; or for a non-wood product with an ISO 14001 or EMAS scheme at the process stage.
The methodology for converting this four-tier system into EcoHomes credits is complicated, with points allocated separately to each individual building element depending on the proportion of certified material it contains. Points for individual building elements are summed to give a total for the building as a whole. Credits are then allocated according to a scale with a maximum of six credits available for “Basic Building Elements” (which includes the frame, floor, walls and roof), and a further three credits available for “Finishing Elements” (such as doors and windows).
In practice, achieving the maximum nine credits for sourcing requires that the majority of building elements are composed of timber certified either to FSC, CSA, or SFI. If PEFC were used throughout in place of one of the three top tier schemes, a maximum of six credits would probably be achievable. Given the current weighting applied to Materials, the result of using PEFC throughout instead of a top tier scheme may be to reduce the overall building score by perhaps 1.5 out of a 100.
While eyebrows have been raised in parts of the wood industry over BRE’s decision to allocate fewer points to PEFC than to the other schemes, three facts are worth emphasising. First, BRE has indicated that the lower score for PEFC is largely due to the UK government’s decision to place PEFC’s “sustainability” status on probation. As soon as this probationary status is lifted, the likelihood is that BRE will raise PEFC to the top tier.
Second, since no other building material may be certified under any of the top tier schemes, nearly all credits for responsible procurement are effectively “bonus points” available to timber alone. Under EcoHomes, no real penalty is imposed for use of uncertified timber in relation to non-wood materials.
And third, the very fact that EcoHomes recognises that a range of schemes provide credible assurances of sustainable forest management is a significant step forward for timber. To date, lack of mutual recognition between the two leading certification brands – FSC and PEFC – has complicated marketing of certified wood. But the rise of EcoHomes means this is less of a problem. Building elements composed of wood certified under a range of certification schemes will be able to achieve the EcoHomes points, and it is the EcoHomes brand that the “consumer” – which may be a construction company, government specifier, architect, or house buyer – will come to recognise. Whether the timber is FSC, CSA, SFI or PEFC hardly seems to matter.
So it is hard to understate the opportunity emerging for timber as BREEAM and EcoHomes become integral to the construction process. Not only does the scheme, at last, give proper recognition to the full life cycle environmental benefits of timber, but it will render obsolete the counter-productive sniping that has gone on between supporters of different forest certification brands.
