Secondary facade layers in building refurbishment and their potential impact on building performance

New building regulations coming into force within the member states of the EU will have a clear impact on building refurbishment of large scale commercial buildings, which will need to comply with minimum requirements for energy performance. The integration of an internal or external face layer whilst retaining the original face offers specific potential for refurbishment of multi-storey office buildings. It reduces thermal losses in winter and minimises disruption caused by construction. This paper discusses basic face refurbishment options for office buildings at the end of a refurbishment cycle, comparing them in respect of their impact on comfort, operational energy performance and future building maintenance. The energy performance of a naturally ventilated cellular office in the UK is simulated, comparing the original face solution with three face refurbishment solutions: a face replacement, a secondary internal and a secondary external face layer. It is shown that whilst improvements in the energy performance of the building can be achieved, provision for some form of summer cooling will be necessary. The relative performance of the three face refurbishment options is discussed and their sensitivity to climate change analysed