Sustainability is an increasingly important issue in today’s construction projects whatever definition one chooses to use, whether the focus is on the ‘triple bottom line’ (environmental, social and economic issues) or simply environmental protection. Manufacturers of architectural and structural precast realised this challenge at a very early stage and are addressing how their products can contribute to the sustainability of buildings and structures, either in terms of the actual performance of a completed building or structure during its life, or through other elements such as the embodied impact of buildings or the construction supply chain’s levels of ethical and responsible sourcing of products and materials.
Another advantage of precast concrete in buildings is the Thermal Mass properties. Thermal mass enables buildings to absorb and release heat in step with its daily heating and cooling cycle and precast concrete products have the properties to enable this. Research has shown that Thermal Mass helps concrete buildings pay back their initial carbon ‘investment’ in less than 11 years.
Unlike other alternatives made up of imported products and raw materials (e.g. timber, metals), the entire supply chain of architectural and structural precast concrete is locally based and bound by UK and EU regulations to reduce its carbon footprint over the next 30 to 40 years. We have already reduced our carbon footprint significantly over the last few years; our partners in the cement industry have reduced their CO2 impacts by 54% since 1990. All ASPA members use recycled steel reinforcement with a considerably lower carbon footprint compared to the BOF-based virgin steel. Between 2008 and 2013, carbon emissions from precast factories decreased by over 26%. The carbon footprint of architectural and structural precast will continue to drop every year to 2050. This has prompted manufacturers of structural and architectural precast to produce a temporary Carbon Footprinting Factsheet to update values currently quoted in databases such as the Bath University ICE Database and the Green Guide to Specification. This factsheet will be replaced by a fully certified footprint in 2015/16.
All members of ASPA are signatories to the long-standing British Precast Industry Sustainability Charter - one of the first construction product sustainability schemes to be introduced in the UK. All members of ASPA are committed to the 14 different environmental, social and economic sustainability principles which form the industry’s Charter. The Charter also commits members to a KPI scheme and a set of 16 sustainability targets to reduce those KPIs. The precast sector is succeeding in improving its performance and regularly achieves the vast majority of the stretching KPI targets.
The most important aspect of any discussion about the sustainability of buildings must be the actual performance of a completed building during its life. This encompasses a broad range of issues such as energy use, water consumption, maintenance cycles, fitness for purpose and even fire safety. It is vitally important to approach the design of sustainable buildings with their whole life performance in mind – a short-term attitude simply will not deliver on long-term sustainability objectives. With a proven service life exceeding 100 years,
years, precast concrete increases its strength for many years after it is cast. Even immediately after installation, it is durable, robust and resists rain penetration, wind-blown debris and in some cases, blasts and chemical attack. The fire resistance properties of concrete are also important. Precast concrete cladding does not catch fire, burn, melt or drop molten particles and can prevent the spread of fire – usually only minor repairs are required after a fire.