PLEA2012 - 28th Conference, Opportunities, Limits & Needs Towards an environmentally responsible architecture Lima, Perú 7-9 November 2012 Simplified life cycle assessment: Applied to structural insulated panels homes JUAN PABLO CÁRDENAS RAMÍREZ 1,2 , EDMUNDO MUÑOZ ALVEAR, 2,3 , FRANCISCO HIDALGO 1 1 Depto. Ingeniería en Obras Civiles, Universidad de La Frontera, Temuco, Chile 2 Doctorado en Ingeniería, Universidad de La Frontera, Temuco, Chile 3 Instituto del Medio Ambiente y Sustentabilidad, Universidad de La Frontera, Temuco, Chile ABSTRACT: As environmental issues continue to become increasingly significant, buildings become more energy efficient and the energy needs for their operation decreases. Thus, the energy required for construction and the material production, is getting of greater importance. This research shows a simplified life cycle analysis study of operational and embodied energy of four new houses located in Temuco - Chile, structured with SIP (Structural insulated panel), in order to quantify the energy at each stage of this construction system. To obtain embodied energy were used two databases in order to quantify the energy of each material, Inventory of Carbon & Energy (ICE), 2008, University of Bath, Inglaterra and New Zealand Building materials embodied energy coefficients database. Volume II – Coefficients, 1998, Victoria University of Wellington, and the energy contained in the panel assembly process, transport and construction of the houses was determined by a data collection company specializing in the construction of houses built in SIP. For the operational energy, computational models were carried out with Design Builder software, with information of the house from thermography and infiltration essays, and this energy was projected at 50 years lifespan. The analysis of the data obtained show that the energy contained by construction processes represents about 1.7% of embodied energy, while the total energy embodied represents 11% of the total life cycle energy of houses, the remaining 89% represents the energy of occupation. On the other hand, we observe that SIP houses generate figures close to 60% savings in energy demand, compared to a common masonry houses with no method of thermal insulation, which were commonly built in this city. Keywords: Construction materials, environmental assessment, Embodied energy, Operational building energy. INTRODUCTION Buildings’ construction has a major determining role on the environment. It is a major consumer of land and raw materials and generates a great amount of waste. It is also a significant user of non renewable energy and an emitter of greenhouse gases and other gaseous wastes [7]. The building sector contributes largely in the global environmental load of human activities: for instance, around 40% of the total energy consumption in Europe corresponds to this sector. According to data from the Worldwatch Institute, the construction of buildings consumes 40% of the stone, sand and gravel, 25% of the timber and 16% of the water used annually in the world [3]. The building and construction sector (i.e. including production and transport of building materials) in OECD countries consumes from 25% to 40% of the total energy used (as much as 50% in some countries) [4]. Because global materials such as cement, aluminium, concrete and PVC are used, the energy costs and environmental impact increasing daily. Naturally, one solution is come back to building sector begin, local materials use with low energy costs and low environmental impact. On the other hand, several studies have shown that operational energy accounts for the main amount of total energy use in dwellings during an assumed service life of 50 years and it is approximately 85–95% of the total energy use [9]. It also represents a major target for improvement, and is generally addressed by most environmental policies. There is a clear interaction between all the stages of a building’s life: for example, if less is invested in the construction phase (e.g. using poor insulation), the investment needed for use and main- tenance will increase. So the question is: is it better to invest in construction rather than in use and maintenance? The application of a global methodology such as LCA will allow us to answer this question, since this methodology can assess the global environmental impact during the life span of a building [2]. However, there are many methodologies proposed in papers with aims to overcome the existing prejudices of architects and engineers about LCA complexity, the difficulties in understanding and applying the results and the loose link with the energy certification applications. In Chile, the LCA methodology applied on building sector it is a new subject and our work it is focused in incorporate embodied energy concept still.