Building Life Cycle Assessment, or LCA, is a quantitative technique of calculating the potential environmental impact of a building’s material, energy, and water consumption, over its full life cycle e.g. 60+ years. One of the benefits of the approach is that in addition to greenhouse gases, LCA calculates other environmental impacts such as water pollution, and resource depletion. It is particularly useful when applied early and iteratively during building design, so that environmental consequences of design choices can be tested, understood and refined. For environmental impacts such as Global Warming, this is becoming increasingly important. New Zealand’s ratification of the Paris Agreement in 2015 means that our country is committed to a 30% reduction in the 2005-level of greenhouse gas emissions by 2030, with this decreasing to zero by 2050. This has a direct impact on the way we are designing and constructing building’s today, as those same building will still be functioning and will be required to operate in this low to zero carbon future.