NOT so long ago home improvement used to consist of a Bank Holiday spent doing a spot of DIY. Modernising the kitchen or adding a bathroom was only for the more adventurous. Today’s homeowners, however, think nothing of calling in a team of builders to convert the loft, extend the kitchen or dig out a basement.

But as such ambitious projects become the norm rather than the exception, do not expect all changes to add instant value to your property. Depending on what you do, you may end up knocking thousands off the price of your home and making it more difficult to sell.

A recent survey by the Royal Institution of Chartered Surveyors said that homeowners were unlikely to add more than 2 per cent to the value of a typical semi-detached house by putting in a basement. An extension such as a conservatory is likely to add 5 per cent and a landscaped garden can add 3 per cent.

Changes that you may not be able to see can make more of a difference than you think. Installing central heating could add 5 per cent and double glazing up to 4 per cent. In most cases, however, laying new carpets and wood flooring adds little value. You might even make your house harder to sell by putting in cheap laminate flooring. Shoddy workmanship, ignoring building regulations or failing to get planning could also backfire.

Above all, homeowners should make sure that their home improvements suit their postcode. Most areas have a ceiling price. Your kitchen might be Smallbone and your bathroom Philippe Starck but do not expect a Chelsea price tag in Chelmsford. George Franks, of Douglas & Gordon in London, says: “By increasing the size of their home and pushing up the value, some homeowners are making their properties harder to sell. The house becomes expensive for an area and is put beyond the reach of many local buyers.”

Our appetite for remodelling our homes is also changing the shape of the market. A decade ago most buyers climbing the property ladder would start with a two-bed flat, move to a three-bed house and then trade up to a four-bedder before moving to the country. Many are now skipping out some of the rungs by trading a two-bedroom flat for a four-bedroom house with potential for growth — and staying put. Which means that while we are saving on the costs of moving, the gaps between each move are becoming wider.

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