THE recent heatwave may lead to households suffering major problems - especially those built on clay soils.

The Royal Institution of Chartered Surveyors has urged houseowners to be vigilant as sustained hot weather can lead to subsidence caused by the loss of water from shrinkable subsoil.

This natural phenomenon, brought about by a period of high temperatures and low rainfall, is a major threat to properties built with shallow foundations, most commonly seen in the construction of pre-1970 houses and particularly during the Edwardian and Victorian eras.

Subsidence arises when the hot spell breaks and rain causes the soil to expand. The expansion is rarely uniform throughout the soil and as a result the ground experiences “differential heave” which can cause buildings to move and crack.

The RICS has produced a free brochure entitled: “What to do when the earth moves.” It is available by calling RICS on 0870 333 1600.