How architects can keep the planning authorities happy and homeowners reassured, by adopting simple, cost effective mitigation measures to both new builds or as ‘retrofits’ to existing properties, explains Frank Kelly, leading flood design engineer the founder of Flood Angel.
After experiencing relatively low levels of flooding last winter, it would be easy to dismiss the devastation of 2103/14 floods as a one off event but the reality is very different. Around 5.3 million homes in the UK are at risk of flooding and the average annual cost to the economy is over £1.4 billion. Yet awareness of flood risk among both homeowners and developers is poor and there is little, if any, understanding of the range of defence measures available on the market to help protect properties.
As a nation, we’re currently counting the cost of introducing retrospective flood protection to homes, businesses and communities. As building land becomes scarcer and the demand for new homes grows, developers are turning to flood plains as a viable alternative. As a consequence, planning authorities are increasingly demanding a ‘flood risk assessment’ as a mandatory requirement of new planning applications.
Regulations
Fire protection has quite rightly been a fundamental part of building regulations for many years. In more recent years environmental sustainability and energy efficiency have been added to the list for priority consideration. As an industry we are pushing for flood protection to be given the same status as these other fundamental regulatory requirements.
Architects, developers and construction companies who appreciate the importance their attention to the risk of flooding will have on their ability
to secure planning approval on projects, are already considering mitigation solutions in the early planning stages of their building and
infrastructure projects.
Evidence shows that by incorporating defence solutions as early as possible in the process, developers can be assured of both long-term protection at a fraction of the cost of post-build installation and, of course, that all-important planning consent.
Modern solutions
The incorporation of solutions to protect the perimeter of a development site is a popular option with developers. Technology, such as automatic flood barriers, which can be deployed with no human intervention, has been successfully introduced to riverside residential developments in both Cornwall and London.
Flood defence can be equally successful on an individual property basis. Although for many, the very term flood defence still conjures up images of sandbags or makeshift wooded boards desperately trying to stem the flow of muddy flood water, the reality is very different. There is a large range of defence products designed to provide holistic flood protection across all areas of water ingress into a property.
Reactive products
Products that offer ‘reactive’ door, brick and sewage protection are a cost effective, easy to install choice. Designed for individual properties, barriers and walls provide effective door defence, while airbrick covers and toilet bungs are both easily deployable in the event of a flood.
Barriers are constructed of highly durable GRP set within lightweight aluminium frames making them easy to install and store. These are specifically designed and manufactured for each doorway of a property and come in a range of fixing options, including non- intrusive inset fixings or aesthetically sympathetic wall-mounted powder-coated rails, enabling the homeowner to choose the best finish for their decor.
Defender walls can be deployed to provide protection for longer spans including garage doors, driveways and patio/French doors. Utilising a simple post and socket installation system, a wall is a cost effective and popular choice in developments where bi-folding and curtains walls are a dominant design feature.
Passive products, active defence
Effective as these reactive products are, by far the most appealing solutions are ‘passive’ defence products that activate automatically in the event of a flood.
Although flood doors may look like standard door at first glance, they are highly engineered flood products featuring specially designed seals and a vertical/horizontal locking system developed in conjunction with specialist lock manufacturers. Doors are manufactured from either white or oak effect uPVC or from a hard wearing composite material that’s available in a wide range of colours.
Bricks and backflow
But doorways are only one route of water ingress into a property. In excess of 5000 litres of flood water an hour can enter a property through a standard airbrick alone. The simple replacement of a standard brick with an anti-flood airbrick, in which an internal flap automatically closes in the event of flooding, is a highly efficient and cost effective solution.
And while all flooding is distressing, the damage caused by sewage backflow is always particularly difficult for the homeowner. The simple addition of a non-return valve to a property’s sewage system will ensure that in the event of a flood, an automatic ‘shut off’ flap activates to stop sewage flowing back into a property.
And finally As the old wives would say “an ounce of prevention is better than a pound of cure”. By researching just a few of the mitigation measures available on the market, installers and homeowners will have a clearer idea of how easy it is to protect a property. Vigilance is essential. Installers should be appropriately qualified to fit products; products should always be Kitemark certified and; should only be supplied by a reputable flood defence specialist.