Evaluating building design options with a focus on simultaneously minimising life cycle greenhouse gas emissions (GHG) and life cycle cost (LCC) is difficult due to a lack of comprehensive and accessible tools. An integrated approach where life cycle GHG and LCC performance can be balanced is essential in order to optimise a building's overall life cycle performance. This paper describes the development of an integrated framework designed to assist building design professionals in optimising the life cycle GHG and cost of a building. This paper demonstrates the framework's potential by applying it to glazing design options for a residential building case study. The demonstration of this framework highlights the fact that options such as triple glazing, often heralded as a solution for reducing GHG, may not lead to as great a reduction in life cycle GHG as options such as double glazing (which also comes at a lower LCC for this case study building). This paper not only highlights the need to analyse and select building design options based on both their life cycle GHG and LCC performance but also emphasises the significant amount of uncertainty attached to decision-making in these areas.