The last 3 years there have been numerous insurance claims for damage to Buildings caused by rainfall & flooding. The following  demonstrate the various ways in which this damage may occur, and to suggest ways in which the risk of an incident, and the magnitude of any consequential damage, may be reduced.

The unusual rainfall patterns seen in recent years have caused flooding problems in areas historically considered to be low at risk, and both the frequency and size of losses have increased significantly.

Rainfall: Building Maintenance

The fabric of the building must be well maintained for protection against the elements. All buildings need frequent and careful examination. Those in elevated positions, exposed to prevailing winds, are particularly at risk from rain entry. The following regular checks are necessary and appropriate remedial action should be taken:

• Check the roof and replace any loose or damaged tiles, slates, ridge tiles and any other roof claddings or flashings.
• Check that flat roof coverings are in good condition, not showing evidence of cracks or splits and are firmly stuck down, particularly at joints. Remember that bitumen felt flat roof coverings must be checked every 3 years.
• Check the condition of roof lights for leaks and cracks or breakages.
• Check and repair as necessary all cement fillets and brickwork pointing, including chimneys, coping stones, lintels and ledges.
• Check that roof gutters and down pipes are clean and unobstructed, kept free from leaves and vegetation. These should be cleaned at least once a year, possibly more often depending on local trees etc.
• Check that if gutters overflow in storm conditions the water will be discharged outside the building. This is particularly relevant to valley gutters and those which run behind parapets, where overflow outlets should discharge through the parapet to the outside of the building. Overflow weirs should be considered if not already fitted.
• Check all internal drainpipes
• Are they protected from mechanical damage and securely fixed?
• Are all inspection covers and rodding eyes easily accessible and free from internal obstruction?
• Are the covers securely fixed to prevent leakage?
• Check the condition of underground drains
• Lift manhole covers and check that the drains are clean
• Make sure that the water runs freely without backing up inside the manhole
• If the pipes are dirty, or the water appears to run more slowly than would be expected, have the drainage system cleaned
• Check that all gullies, gratings and drainage channels both inside and outside the building are clean and free from obstruction.
• It is possible that, despite having done all these things, you might still encounter problems with rainwater drainage systems. Typical problems are:
• Gutters that regularly overflow (even though they are clean and well maintained).
• Constant damp patches on walls
• Puddles that collect on flat roofs in wet weather.

These indications of inadequate drainage design will need specialist attention and you should seek professional advice.