Emission Accounting of a Wooden Passive house from Life Cycle Perspective Comparison of embodied and operational energy for different wooden envelopes and structures

This studied focused on life cycle assessment (LCA) of a Passive House and investigated the impact of using wood as a main material in envelop and structure in terms of CO2 emission. The studied Passive House is a residential blocks located in Mandal along the river in south of Norway. It is based on a competition entry conducted by LINK Arkitektur designed after Norwegian Passive House Standard. The focus was on accounting of CO2 emission of operational and embodied energy related to different wooden envelope and structural elements. Life Cycle Assessment was limited to manufacturing and replacement phase in lifetime of 60 years. The assessment was carried out using database EcoInvent and by means of SimaPro and SIMIEN; an energy simulating software from Norway. To simplify the research and speed up the process, the calculations were based on a 1 m2 of an apartment in 5th floor as the base case. The comparing of options in terms of emission accounting and considering thickness and weight resulted in selection of the best option which then was scaled up to the total heating area and compared to ZEB ShoeBox model as reference case. Comparing the results showed that the effort of selecting low emission materials resulted in reduction of CO2 emissions. The practice of LCA in early phase of building design provided a better comparison of building products in terms of environmental impacts.