Learning from Doris; future proofing our building stock

dorisStorm Doris which tore through Britain recently wreaked havoc with gusts hitting 100mph and heavy rain pounding homes right across the country. Similarly in the winter of 2015, extreme storms led to the highest river flow levels ever recorded and  resulted in widespread flooding and property damage costing £1.3bn[1] causing many people to be evacuated from their homes[2]. Despite the significant investment in flood defences that has taken place over recent years, around five million properties in the UK today are at risk of flooding[3].

The Intergovernmental Panel on Climate Change (IPCC) has warned that extreme weather events such as these are likely to become more prevalent with an increased risk of intense rainfall and flooding.[4] Projections from the Committee on Climate Change[5] suggest periods of intense rainfall could increase in frequency by a factor of five, meaning more homes would be exposed to a greater risk of flood damage. Wetter weather poses significant challenges for our building stock.

Efforts to tackle the UK’s housing crisis means we need to build more homes, but these homes need to be future-proof, both in terms of energy efficiency and safety. The benefits of energy efficiency improvements are well documented, however it is equally important that homes are also protected from flooding. A key solution to ensure this and reduce the costs associated with flooding is to install property level flood resilience measures, which will prevent water ingress and/or aid recovery.

In addition to building future proof homes, it is important that existing homes are also protected. The government wants to drive one million energy efficiency retrofits by 2020 but should also take into consideration the flood resilience of thermal insulation in high risk areas. Currently, when a building is flooded the tendency is to go with the status quo, replacing damaged plasterboard, flooring and insulation with like for like materials. However, highly resistant and resilient replacement products should be used to ensure that the property is better protected by subsequent flooding. For example, closed cell insulation does not absorb or transport moisture and has been recognised as the preferred solution when seeking to improve the flood resilience of buildings[6]. The BRE recently created a demonstration home with the aim of raising awareness amongst householders, contractors and the industry of the most effective ways of refurbishing and repairing properties that have been flooded and that may be at risk of subsequent flooding. The BRE refurbished a Victorian Terrace house with measures which are resistant to flooding and resilient to the effects of being flooded[7]. The home included flood resistant PIR and PUR insulation supplied by BRUFMA members[8].

There is no single solution but we need to be better prepared. Our buildings built and retrofitted today need to be able to meet tomorrow’s requirements. Preventative measures play a key role in reducing the risk of flooding, however given that flooding will become more widespread and more frequent, we need to adapt our homes to be resilient to flooding. This means that building standards and regulations should be set to ensure our buildings use the most energy efficient and flood-resilient insulation products to reduce the damage and cost associated with increased flood risk and also allow properties to quickly recover from water ingress. Moreover, as recommended in the Household Flood Insurance briefing paper released last week[9], insurance models and premiums should reflect the risk of flood damage by taking into account flood resilience or resistant measures.

[1] https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/551615/flood-resilience-bonfield-action-plan-2016.pdf

[2] http://researchbriefings.parliament.uk/ResearchBriefing/Summary/CBP-7424

[3] https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/292928/geho0609bqds-e-e.pdf

[4] https://www.ipcc.ch/publications_and_data/ar4/wg1/en/faq-10-1.html

[5] https://www.theccc.org.uk/2015/12/07/uk-floods-climate-change-likely-to-increase-frequency-and-magnitude-of-severe-flooding-events/

[6] https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/7730/flood_performance.pdf

[7] https://www.bre.co.uk/floodhouse

[8] Products from BRUFMA members Isothane, BASF and Kingspan were used in the project

[9] http://researchbriefings.parliament.uk/ResearchBriefing/Summary/SN06613#fullreport