Abstract

The 5th Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) reports important evolutions in the climate system. These changes are likely to affect the durability of the built environment. Although many contemporary studies investigate the future energy efficiency of buildings, research on the impact of climate change on the hygrothermal behaviour and degradation of building envelopes is rather scarce. Using climate projections, we studied the advantage of ‘hygrothermal response based‘ analyses over ‘climate based‘ analyses when assessing the impact climate change on façades. This paper presents a sensitivity study on solid masonry wall assemblies, before and after internal retrofitting, using three RCP (Representative Concentration Pathways) projections of the ALARO-0 Regional Climate Model at the grid point of Brussels (BE). The findings suggest the necessity of a ‘hygrothermal response based‘ analysis to study the sensitivity of the building envelope to climate change. Moreover, the largest sensitivity is observed for RCP 8.5, the scenario having the highest projected greenhouse gas concentrations by the end of the century.

Abstract

Mould growth is a biodeterioration phenomenon that jeopardizes the integrity, functionality and durability of building envelopes. The performance to withstand biodeterioration depends on the critical hygrothermal conditions inside the envelope. These conditions are subject to the configuration of building envelopes, and climate exposure, accounting for both the outdoor weather and indoor environments‘ conditions. These critical conditions are likely to intensify in response to the changing climate, and hence, modification and adaptation of the envelopes‘ configuration will be required. An understanding of the implications of envelope configurations‘ choices is required to set up guidelines for forthcoming building envelope design. Parametric analyses are a potent source of insight to investigate how the input parameters influence the desired outcome. In light of this, a parametric analysis is carried out to investigate the performance of three building envelopes to withstand mould growth. The impact of climate change in the performance evaluation is accounted for by employing both historic and future climate change scenarios in which the global climate temperature change is forecast to be 3.5º C. Input parameters related to the simulation of mould growth are also investigated. Recommendations to current building envelope design guidelines are drawn for the performance evaluation to withstand mould growth