How green is your house: labelling catalogue house’s CO2 emissions with aid of LCA

Abstract

Of Sweden’s 4.8 million households, almost two million consist of privately owned detached houses. The Swedish catalogue house market produces around 4000 new houses every year. This is an industry that contributes to the building sector’s large share of Sweden’s total greenhouse gas emissions. Despite this, the catalogue house manufacturers lack information about the environmental impact of their houses. With this year’s new law from Boverket requiring new larger buildings to be climate declared, it will also become important for catalogue house manufacturers in the future to exhibit their house’s CO2 emissions. The purpose of this study is to examine and understand how to communicate the environmental impact of catalogue houses. The aim is to create environmental labelling of the house’s CO2 emissions with aid of life cycle assessment. Together with the labelling, a design proposal for a CO2 optimised catalogue house is created. Both new materials, building components, latitudes and houses lifespans are investigated. Main research question examines how customers of catalogue houses can be influenced to make more sustainable choices by communicating the house’s CO2 footprint in an understandable way with the help of LCA. The thesis subject is explored by using the methods research for design and research on design. Interviews, literature studies, document analysis and study of existing certifications is being conducted. Case studies of catalogue houses, reference project and carbon footprint calculations are executed with the tool CAALA to help apply the information of CO2 footprint into a labelling system. The result shows that CO2 footprint can be communicated with aid of labelling in an understandable way for a catalogue house customer. The houses can also be compared to each other with the aid of traffic light label bars. By changing the building materials and constructions to CLT-wood and foamglas a significant reduction of CO2 emissions can be done. The roof and foundation are the building parts that emit most CO2. The most green house calculated is a house with a small roof and foundation area, even though that house has the biggest living area.