Comparative LCA of a concrete and steel apartment building and a cross laminated timber apartment building

In this paper an LCA is carried out on a concrete and steel apartment building and a cross laminated timber apartment building to compare the greenhouse gas (GHG) emissions from the two buildings. The buildings are built by Veidekke Entreprenor AS and they are almost identical except for the structural system and the number of floors. They are connected by an underground car park of reinforced concrete. The product stage (A1-A3), transport to the building site (A4) and operational energy use (B6) is examined. Results show that the cross laminated timber building has 25% lower GHG emission compared to the concrete and steel building when looking at the production stage, and 13% lower emissions when looking at all stages. The results also show that the material that contributes to the most GHG emissions is reinforced concrete, and that the underground car park has a high GHG emission because it consists of a lot of concrete. What is new in this paper is that there are two real buildings close together that can be compared to find out which has the lowest environmental impact. The paper is valuable for people designing environmentally friendly buildings with a low carbon footprint.