The RICS has developed an online cost calculator for home-owners to work out the cost of rebuilding their houses.

The calculator, developed by RICS arm the Building Cost Information Service (BCIS), will help those house owners renewing their house insurance, which is based on rebuild costs, not the market value of a property.

The site asks a few simple questions on the age, type and quality of the property and also gives tips on measuring the size of your house/flat.

BCIS director Joe Martin said the calculator could offer surprising results. He said: “Few people realise that insurance on buildings is driven by construction inflation rather than market prices. Rebuild costs are not always proportionate to size and market value. It is possible that a highly valued, new-build house in Mayfair will need to be insured for less than a Victorian terrace in Bridlington.”

To use the calculator go to http://calculator.bcis.co.uk