Carbon Footprint Assessment of a Residential Development Project

Buildings account for roughly one third of all green house gas emissions globally. Identifying the sources of these emissions and understanding their relations to the construction phase is essential in climate change mitigation. This study evaluates the carbon emissions caused by a residential construction project in Finland. The research method is modified tiered hybrid life cycle assessment. The study shows that the carbon emissions of a 220 homes development project are around 60 000 tons of which 90 percent initiates from actual buildings and ten percent from the supporting infrastructure. The sources of the carbon emissions are divided into numerous categories without any single dominant category. Thus, reducing the emissions requires a holistic management approach, as there are no single dominant materials in terms of carbon emissions. Also, the costs were found to poorly correlate with the carbon emissions, which implies that the traditional cost management strategy used in project management cannot directly deal with carbon management challenge. In addition, the results indicate that because of the rapid and high carbon spike of construction, the construction phase emissions are much more significant regarding the climate change than their share of the buildings' life cycle emissions would suggest. The study also shows that a generic LCA data model can be used to roughly estimate the emissions of a development project, but that a more detailed project specific data is needed for more accurate results. The difference between a generic and a project specific model were calculated to be roughly 20 percent. The results of the study may be applied to the evaluations of similar construction projects. The research method may also be used in future research as well as in further development of hybrid LCA methods.