Should the Passivhaus standard include the environmental impact of materials in its standard?

Human activities are significantly contributing to an upsurge of greenhouse gases that lead to climate change (IPCC, 2014). Building construction and operation are responsible for ~40% of energy consumption worldwide and for ~30% of the greenhouse gases emitted into the atmosphere (UNEP, 2009). These high emissions has forced UK authorities to promote mitigation measures to improve the energy efficiency of buildings, hence reduce energy consumption (e.g. the EU’s EPBD demands ‘nearly-zero energy buildings’ by 2020). At present, operational energy in buildings and especially space-heating, which represents the highest proportion of energy use in UK housing (Shorrock, 2005), are regulated in building codes. However, in order to reduce this operational energy, there is usually an increased demand for high-intensity materials and construction processes which, although they may improve the building energy performance, in turn increase the building’s embodied energy (Lane, 2010, Crawford & Stephan, 2013). An unintended consequence of regulations imposing the design of low-energy buildings may be that they require more energy for their construction (Lane, 2010), leading to an increase in associated CO2 and CO2e emissions (CO2e : the greenhouse potential of emissions, considered as if they were all CO2 – Pelsmakers, 2012). This paper discusses whether the environmental impact of materials used in the design of Passivhaus buildings should form part of the Passivhaus (PH) Standard, alongside its operational energy requirements. The paper presents research results from an investigation of an as-built PH case study located in the UK.