Loud carpets, garden gnomes, pebbledash and other "design crimes" cost British home sellers almost £10 billion a year, according to a new survey.

Property experts have identified 12 key factors that can knock thousands off the price of a house

Limescale or "grey goo" around the bath, bad decor and dead pot plants also deter buyers.

"Buyers are looking for every opportunity to get your house for less, so first impressions really count," said Justin Ryan, from The Million Pound Property Experiment, a BBC show starting this week.

He said a dead pot plant might indicate an airless or "sick" house, while dirty light switches hint at worn out wiring, reducing a home's value by around £3,000.

Plastic double-glazing windows in an old or period property could cut up to £10,000 off offers.

Tacky garden gnomes knock £500 off the price of a home, while bold or clashing colours can cost over £1,000.

The survey of 7,878 home owners was conducted by the Radio Times.

The Million Pound Property Experiment starts on BBC2 at 9pm on November 5.

Monday November 03, 2003