The simulation of the post flood drying of dwellings in London

Abstract

Climate projections indicate that the UK will experience more frequent extreme precipitation events and a rise in sea levels, with the greatest relative sea level rise occurring in the South-East of England. As a result, flooding is expected to occur more frequently in London. Flood simulation modelling has previously been done to predict the impact on the built environment for a variety of scenarios for London. However, such models have not taken into account the detailed hygric behaviour of the building stock under flooding and drying conditions which can vary significantly between property types, and can lead to prolonged damp and health problems. To address this problem, a building stock model of central London has been developed in a Geographic Information System (GIS), with information on the age, structure, and height of each dwelling and assumptions about built form based on historical building standards and surveys. This paper describes a novel methodology for the development of a building stock model with the necessary information to carry out hygrothermal simulations of the penetration of water into the building envelopes of flooded homes and the subsequent drying under different environmental scenarios. It discusses how the risk of damp in flooded homes can be modelled using hygrothermal methods and supplemented with mould models. By combining the multidisciplinary components of GIS, building simulation, and microbiological modelling, a holistic picture of the potential health implications of flooding at a population level across different temporal and spatial scales can be developed.