Police are urging householders to secure their sheds to prevent them from being broken into during the spring and summer.

The warning is being issued because 8644 sheds were broken into during 2004. Shed burglaries rise unnecessarily between May and July every year.

Opportunist thieves target sheds, which are often at the bottom of a garden or an allotment, knowing that valuable property is stored inside. The average shed can contain property worth up to £2000.

Criminals see the contents of a shed as rich pickings. The property stolen is likely to be sold at car boot sales or via internet auction sites, making it virtually untraceable. Even sheds that do not contain valuable items usually have tools, which can be used by thieves to break into homes.

Mike Terry, from Stoke Bardolph, lost a £350 mountain bike when his shed was broken into last year. He said: "When my shed was burgled, I had a mountain bike stolen, which was a gift from my wife for my birthday nine months before… …What compounded my misery was that my home insurance didn't cover the items in the shed."

"My wife also felt very insecure after the event, worried that the intruder may come back again and possibly break in to the house next time. We therefore purchased a shed alarm and strong bolt lock for the side gate, which have both been used every day since the event."

Crime reduction spokesman Peter Ainley said: "Whenever possible, mark valuable items with your post code using a UV pen or SmartWater."

"By chaining your valuable items together and securing them to an anchor point, you can make them difficult for thieves to steal."

By taking simple preventative measures you can make your shed more secure:

• Ensure your shed is kept in good condition and fit good physical security.
• A lighting system that covers the area of the shed can deter criminals.
• Most shed doors open outwards with the hinges exposed. To prevent these from being removed to gain access replace the screws with dome head coach bolts.
• Most thieves gain entry by forcing off the lock. Use a heavy-duty hasp and staple (also known as a pad bar) and secure it with suitable coach bolts and locking nuts.
• The padlock needs to be a good quality hardened steel of the close shackle type to prevent it from being cut off.
• Fit metal grills to windows and secure by screwing into metal plates inside the shed.
• Prevent the thieves from window-shopping by boarding the windows over on the inside or put up net curtains.
• Fit a shed alarm to the door of your shed this will warn of any attempted break into your property.
• Take photographs of any valuable items. They can be used to identify stolen property.
• Security mark as many items as possible with your postcode and house number or first two letters of your house name.
• Consider using brightly coloured paint to mark your property to enable it to be identified from a distance.
• Gardening tools and sports equipment are not cheap but can be sold on easily by thieves.
• Chain valuable items together and secure to a fixed solid anchor point.
• If you do keep valuable items such as cycles, fishing tackle and golf clubs in the shed ensure that they are adequately covered by your insurance policy.