Document Type

Theses, Masters


Available under a Creative Commons Attribution Non-Commercial Share Alike 4.0 International Licence


Architectural design


The Passive House standard represents perhaps the current 'state-of-the-art' in low-energy building design, often hailed by its advocates as a cost-optimal standard to be applied to both new and existing dwellings in order to achieve Ireland’s energy and CO2 reduction targets. However, meeting the rigorous standards of Passive House in existing buildings is demanding and generally requires significantly higher initial capital investments. This research conducted an investment appraisal of the Passive House retrofit standard in order to determine if it could become a cost-optimal model for the deep-retrofit of Irish dwellings. The problem was investigated using energy analysis (DEAP v3.2) and Life Cycle Cost Analysis tools (BLCC5), applied to a real-life case study Passive House dwelling retrofit project. An individual approach was developed for assessing the project’s initial capital costs, as well as future operational costs. Total life cycle costs for the baseline (pre-retrofit) dwelling, the Passive House retrofitted dwelling, and a range of alternative retrofit scenarios were computed. An economic appraisal, using Life Cycle Cost Analysis together with sensitivity analysis, demonstrates that the deep retrofitting of an existing dwelling to the Passive House standard can be cost optimal, when longer investment periods (≥ 30 years), lower discount rates (≤ 4%), positive fuel inflation (≥ 4%) and inclusion of residual values are considered.