The EU Consumer Footprint aims at assessing the potential environmental impacts due to consumption. The calculation of the Consumer footprint is based on the life cycle assessment (LCA) of representative products (or services) purchased and used in one year by an EU citizen. This report is about the consumer footprint indicators of the basket of product (BoP) on housing. In order to assess the environmental impact of EU housing consumption, a LCA-based methodology has been applied to twenty-four representative dwellings (basket of products), modelled on the basis of the type of building (single or multifamily houses), the year of construction (four timeframes), and the climate zone (three zones) in which they are located. One of the main novelty of this work is the definition of twenty-four archetypes of buildings, changing the construction materials and the building specific features affecting the inventory for each archetype. The resulting baseline inventory model, referring to the year 2010, was assessed for 15 different impact categories, using the ILCD LCIA method. A sensitivity analysis has been run for some impact categories, with a selection of recent impact assessment models and factors. Results allows a wide array of considerations, as this study reports overall impact in Europe, average impact per citizen, share of impact due to dwelling typology and climate areas, as well as impact of each dwelling type per climate zone per year of construction. Single-family houses are responsible for the highest share of impacts. The same type of building has different impacts in different climatic zones, especially because cold climate requires higher input of resources for space heating. The overall results reveal that the use phase (energy and water consumption) dominates the impacts, followed by the production of construction materials. In general, electricity use and space heating are the activities that contribute the most to the overall impacts. Depending on the normalisation reference used (European or global) the most important impact category present a different relative share. However, human toxicity, respiratory inorganics, resource depletion (metals, fossils, and water), climate change and ionising radiations show the highest impacts for all the normalization references. Since many LCA study on housing are limited to the assessment of climate change related emissions, the BoP housing baseline aims at helping understanding the wider array of impacts associated to the housing system and the potential areas of ecoinnovation improvement for reducing the burden. To assess potential benefits stemming from selected ecoinnovation, the Consumer Footprint BoP housing baseline has been assessed against nine scenarios, referring to improvement options related to the main drivers of impact. The nine scenarios covers both technological improvements and changes in consumers behaviour, entailing: 1. night attenuation of setting temperature for space heating; 2. external wall insulation with an increased thickness; 3. external wall insulation comparing conventional or bio-based materials; 4. use of a solar collector to heat sanitary water; 5. floor finishing with timber instead of ceramic tiles; 6. a building structure in timber compared with concrete frame; 7. implementation of smart windows for improved energy efficiency; 8. a combination of selected above mentioned energy-related scenarios; 9. production of electricity through a photovoltaic system installed on the roof. The assessment of the selected scenarios, acting on energy efficiency, resource efficiency, renewable energy and bio-based material (scenarios 1 to 7) revealed that the potential reduction in impact for each of the eco-innovation assessed is relatively limited and that a combination of actions is needed to achieve significant improvements. Moreover, in the case of scenarios acting on the substitution of specific components of the building, the potential improvement is proportional to the relative importance of the substituted component in the baseline scenario. However, a preliminary modelling of combination of energy-related measures (scenario 8) proved to be a good way to enlarge the potential benefits coming from the selected improvements of the building stock. The results highlight as well that LCA is fundamental for unveiling trade-off between benefits associated to eco-innovation and burden arising from their implementation.
