This report summarises evidence collected by the Defra research project FD2682 regarding technical aspects of low cost flood repairable approaches designed to limit damage to buildings. It is derived from a Rapid Evidence Assessment (REA) that is reported in greater detail in the accompanying REA report. Flood repairable measures applied to buildings are designed to limit damage or speed recovery once water has entered a property. They include strategies to keep water away from building elements (such as raising power sockets) and the use of waterproof or water resistant materials, including those capable of retaining their integrity and recovering quickly after inundation. The measures are useful when water exclusion approaches are not practical or cost effective, and also as an addition to water exclusion approaches as a failsafe.
The REA comprised a systematic scoping of relevant academic and grey literature; consultation with a panel of experts; interviews with professionals from the sphere of flood reinstatement and property protection; and interviews with occupants of properties where flood repairable approaches have already been adopted. This was followed by an assessment of the costs and benefits of selected low cost flood repairable measures and of illustrative packages of low cost repairable measures.
The review found 139 suggested measures that could be regarded as flood repairable, over half of these being ‘low cost’ or ‘low additional cost’ (for example, when adopted during reinstatement or other building work) and which will prove to be cost beneficial for properties in the UK. Four packages of measures were costed. Three of the four packages evaluated could result in a pay back after just one subsequent flood (assuming they were successful in preventing damage). The most appropriate measures for any individual property depends upon a combination of factors, however, including the structure and condition of the building itself; the nature of the flood risk; and the preferences and lifestyle of the occupants.
Scientific evidence on the performance of measures was found to be scanty, but the experts in the industry were seen to be successfully applying experiential knowledge along with current guidance on an ad hoc basis. The wider industry was seen as less well informed, with some flood repairable features being removed at reinstatement, as their purpose and value is not yet understood.
The report concludes that further research is needed to provide evidence of the potential effectiveness of flood repairable approaches. Attention should also be directed towards understanding the performance of flood repairable measures during and after floods to ensure that the potential effectiveness is realised in practice. Improved technical guidance and training is recommended to further develop the understanding and awareness within the flood damage industry.
Lamond, J., Rose, C., Joseph, R., & Proverbs, D. (2016). Supporting the uptake of low cost resilience: Summary of technical findings (FD2682)