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Environmental Profile
The SupaWall System® that comprises SupaWall®, SupaRoof® and SupaFloor® has excellent sustainability and environmental credentials. This is because it essentially consists of two elements, both of which have similarly excellent credentials:
The sustainability and environmental performance of timber frame is well-known and emphasised by publications from wood for good (www.woodforgood.com) and the UK Timber Frame Association (www.timber-frame.org). For instance, the latter notes that"... timber is, without question, the most environmentally acceptable material used in modern construction. No alternative material offers the following unique combination of Although possibly less well known, polyurethane insulation also has good sustainability and environmental performance. This is best summarised by the fact that polyurethane insulation also carries the BRE Green Guide "A" Rating (the same as, for instance, sheep's wool insulation). Today, about 45% of fossil fuels are used to heat and cool the interiors of buildings and homes. Through the use of insulation materials, considerable energy savings are achieved. This results in a substantial reduction of CO2 - one of the main contributors to global warming (Ref.3). Polyurethane rigid foam is one of the best available insulation materials for the construction of new buildings as well as for the renovation of existing buildings.
The SupaWall System® uses SupaWall® foam type 100.3 that has been specially developed to have the following environmental pedigree:
Polyurethane foam is used extensively in the construction industry. In residential housing, polyurethane foams insulate roofs, walls and floors. Other benefits such as structural strength, water vapour resistance, durability, space-saving and lightness make rigid polyurethane composite panels such as SupaWall® a suitable material for many commercial, as well as domestic, buildings (Ref.4).
Life-cycle analysis (LCA) carried out on the polyurethane raw materials (MDI and polyols) and extended to the polyurethane rigid foams, delivers unambiguous energy, material and emission figures (Ref 3). It follows that polyurethanes are comparable with many other plastic materials on a unit weight produced basis. Hence, when applied to low density foam, they need less resources per unit volume. These materials can either be recycled after use, or their energy content can be recovered, thus releasing the inherent energy "borrowed" to provide the better heating and shelter.
Eco-profiles are available for the rigid polyurethane foam itself (Ref. 5) and also for its constituent parts - MDI and polyols (Refs 6 and 7). It is unusual to see this with materials used in construction and this demonstrates the high level of confidence in its environmental performance. These references show the gross or cumulative energy to produce 1 kg of rigid polyurethane foam/1 kg of MDI/1 kg of polyols; this same data expressed in terms of primary fuels; shows the energy data expressed as masses of fuels; the raw materials requirements; the demand for water; the gross air emissions; the corresponding carbon dioxide equivalents of these air emissions; the emissions to water; the solid waste generated and the solid waste in EU format.
The winning materials over the next decades in terms of minimising resource consumption will have to be durable. Indeed, in many cases the impact on soil, water and air can be much reduced, provided that the materials and articles, designed for a specific purpose and use pattern, become optimised in terms of service life to match the human needs. The life-span of polyurethane in the SupaWall System® is over 60 years, further improving its Total Life performance.
Thanks to their excellent insulation properties, polyurethanes play a key role in creating energy saving solutions, and contribute significantly to the European Union's target of 8% reduction in greenhouse gases. This meets targets which were agreed at the world climate change conference in Kyoto in December, 1997. Thus the performance achieved by the excellent combination of timber frame and polyurethane insulation in SupaWall® delivers at the highest aspirations of the Code for Sustainable Homes in England & Wales and that proposed by the Sullivan Report in Scotland. Effective insulation is essential in reducing fuel and energy costs. Current efforts to control global warming emphasise the need for energy conservation. Industry experts estimate that worldwide insulation of buildings to optimum standards could reduce global energy requirements by more than 10%.
References
1. "Environmental Performance - The Benefits of Timber Frame Construction". UK Timber Frame Association. 2. "The Green Guide to Specification", bre global, (http://www.thegreenguide.org.uk/). 3. "Polyurethanes - Sustainable Materials", ISOPA, the European Diisocyanate and Polyol Producers Association. 4. "Living with Polyurethanes", ISOPA, the European Diisocyanate and Polyol Producers Association. 5. "Eco-profile of rigid polyurethane foam", PlasticsEurope, Association of Plastics Manufacturers. 6. "Eco-profile of MDI", PlasticsEurope, Association of Plastics Manufacturers. 7. "Eco-profile of polyols", PlasticsEurope, Association of Plastics Manufacturers. For further information, please use the SupaWall Limited contact details. |
environmental benefits ..." It then goes on to list a wide variety of advantages including, that wood is effectively a carbon-neutral material and that it has low embodied energy (Ref. 1). Timber Frame carries the BRE Green Guide "A" or "A+" Rating (Ref. 2) depending on the cladding.
It is true that polyurethane materials will use up a finite amount of energy for their production as was researched in the LCA work (see left). However, when compared to the energy savings during use, the cumulative yearly energy saving far outweighs the initial, once only, energy input - see graph to the left. Considering that much of the "borrowed" energy of these materials can be recovered after use, the resource loop is virtually closed.
