The building industry is under increasing pressure to get greener to address the problem of global warming and diminishing natural resources. UK Technical Director, Peter Sach, of Durisol, developer of the innovative Durisol wall form system, looks at ways of meeting the green building challenge through the use of sustainable, eco-friendly construction methods and materials.

The European Commission recently confirmed the goal of cutting 20% from Europe’s carbon emissions by 2020 compared with 1990 levels. As its contribution, Britain must cut emissions by 16%, which is a major commitment and is unlikely to be achieved simply by switching our televisions off standby and fitting low energy light bulbs. It is therefore vital that all new buildings, whether houses or hospitals, are designed and built to be more energy efficient and improvements to existing properties should also reflect the need to reduce emissions.

However, it’s not just the energy generated once a building is occupied that needs to be considered. The production, use and disposal of building materials accounts for significant quantities of energy. Indeed, according to the BRE and various other bodies, manufacturing materials and building on site accounts for 30% of a residential building’s lifetime carbon dioxide emissions. The call for greener building is a direct response to this and is all about ensuring that a structure is resource efficient during construction and beyond.

As far as new houses are concerned, the Government is promoting greater construction efficiencies in its ‘Code for Sustainable Homes’. This replaces the EcoHomes scheme and measures a dwelling’s sustainability across six key design categories, including the materials used to build it. Using environmentally friendly materials for constructing the key elements of a house - the roof, external and internal walls, separating floors and windows - makes a vital contribution to a building’s overall sustainability rating under the new Code. This rating is measured across a number of factors, including the product’s embedded energy and its life cycle energy rating, typically measured over 60 years. The latter takes account of the product’s environmental impact from the ‘cradle to the grave’ so to speak, including repair and maintenance. It also covers the effect of dismantling or demolishing a building at the end of its life and whether the materials can be recycled, for example.

I believe few would now argue that green building is not simply desirable, it is a necessity. But how do you ensure that focusing on a product’s sustainability doesn’t compromise other equally important considerations, such as cost, availability and ease and speed of installation? A sustainable building product must satisfy certain criteria in terms of its production, what it is manufactured from and its contribution to a building’s overall energy efficiency. In developing Durisol, the original stay-in-place wall form system, I believe we’ve addressed most, if not all these issues. The result is an innovative and durable building solution that can help decrease a building’s carbon footprint whilst also assisting faster build times.

The use of recycled material, that is in itself 100% recyclable, is at the heart of a green building product and Durisol interlocking wall units are manufactured from at least 80% FSC recycled waste softwood bonded with a proprietary cement/PFA (Pulverised Fuel Ash) mix. This mix dilutes the environmental impact of cement which is a practical and unavoidable ingredient because of its reliability – proven over more than 50 years since the first Durisol units were laid. Our wall form units are so rugged that the infill mix can use recycled aggregates in a high slump concrete. And the casing of Durisol material is both a vapour barrier and a breathable membrane – which does away with the need to wrap the entire building in a film.

As far as speedier construction is concerned, the interlocking modular units are simply dry-stacked, with no need for mortar or bricklaying skills, and then filled with concrete to create solid walls with excellent thermal and sound insulation. Indeed, as the insulation is located on the exterior of the concrete core, the units benefit from a high thermal mass which contributes to lower energy requirements.

Durisol has made its range even greener with the introduction of new wall form units with integrated Rockwool mineral fibre insulation, a green material in itself which enables U-values as low as 0.21 plus a noise reduction coefficient for sound absorption as high as 0.95, without additional insulation or finishes. The Durisol wall form system uses no petrochemicals with no potential for off-gassing. Life cycle costs have also been considered in the development of the Durisol wall form system. The units are very durable and will not rot or decay. They are also resistant to damage from vermin and wood boring insects and do not support fungal or bacterial growth.

The building industry must rise to the challenge of green building in the bid to tackle the damaging impact of climate change. At Durisol, we believe materials manufacturers can play an important role in developing green solutions that satisfy increasingly stringent environmental standards without losing sight of the industry’s continuing need to remain competitive in terms of cost and construction time, and that the Durisol system truly delivers a ‘green solution without the premium’.