454: Ecological optimisation of thermal insulation

New legislation, most notably the EU Energy Performance of Buildings Directive (EPBD) has brought more stringent requirements on the operational energy consumption of buildings. However, the energy and emissions corresponding to the construction and maintenance of buildings are often significant as well. The life-cycle of building materials, building constructions or whole buildings "from cradle to grave" can be evaluated using the method of life cycle assessment (LCA). LCA is a tool for measuring the environmental performance of products, such as building materials, building constructions or whole buildings. Measures like the change of windows or additional insulation of the envelope aim at the reduction of operational energy, but at the same time result in an increase of embodied energy for production and maintenance. Future amendments to the Building Regulations are expected to further cut energy and CO2 emissions, and approach the level of passive houses in 5-10 years. This paper describes a methodology developed for the environmental analysis of residential buildings. The use of the methodology is presented and demonstrated for single-family houses and typical building systems in Hungary. The contribution of the life cycle phases is determined and the effect of increased thermal performance is analysed. The paper analyses whether thermal insulation has ecological limitations for conventional homes. The optimum point of thermal insulation is sought in an example.