EXCURSIONS / Going overboard: It's time to dust down that old bath and rotting wardrobe and head for the Norfolk coast. Alexandra Buxton sets sail

Burnham Overy Staithe, in north Norfolk, is one of those unpretentious dinghy-sailing places where the same families holiday each summer for generations. At high tide, the tiny harbour is briefly full of water and clinker boats flit to and fro in the creek. Children crab off the quay and the ferry does a brisk trade transporting picnickers to the sandy beach at Scolt Head Island.

Early this morning, the normally sleepy scene will be disturbed by cars arriving with old baths, wardrobes, oildrums and palletts lashed to their roof racks. These are the raw materials for Build-a-Boat day, an annual test of amateur marine ingenuity, when anyone who ever dreamed of being Robinson Crusoe, is invited to make a boat in a single day and sail, or paddle, it out to the island.

The idea for Build-a-Boat day emerged five years ago during an evening's drinking at The Nelson pub, Burnham Market. Chris Geering, a builder, was sharing a few pints with five young people known locally as 'the boat boys'. Newly-graduated from college, the boat boys (one a woman) constructed, from scratch, an ocean-going ketch to take them around the world. Overy Action, currently cruising in the South Pacific, is the largest boat ever to have been built at Burnham Overy Staithe.

'Inspired by the boat boys, who were endlessly resourceful, I thought it would be fun to see what people could make in a day using a few cheap materials,' Chris Geering explains. 'So we put up a few posters saying 'Come and build a boat'. More than 20 boats were built in the first year, some by one person alone, some by families or groups. An actor friend made one using everything he found in his garage.'

Build-a-Boat is now an established feature of summer at Burnham Overy Staithe. A number of distinct classes have surfaced among the highly innovative contenders - sanitary (bath tubs), sartorial (wardrobes), somnulent (beds) and pneumatic (tyres).

As organiser, Chris Geering has become an expert in fathoming the seaworthiness of improbable craft. 'Bath tubs are popular but don't really sail brilliantly. They are not sufficiently streamlined. Pallets are easily obtainable, and float, but they're horribly sluggish. One year a dentist paddled out on a pair of giant inflatable lips.'

Entrants in Build-a-Boat arrive early in the morning and spend all day working on their designs. Half a dozen power lines are strung up from the nearby boathouse and there's much swapping of tools and hardware. Quantities of hardboard are available for sale but materials should cost less than pounds 10 in total. Although there are those whose boatbuilding skills shine through, the accent is on inventiveness rather than slick workmanship.

Inevitably, the first casualties sink soon after the hooter sounds off. 'We have a special prize for the first to sink, something carefully selected, like a pair of goggles. One year it went to a Cambridge solicitor whose sailing cupboard foundered a few feet from the shore,' Chris Geering says. 'Another boat, a twin hull, unexpectedly divided into two parts.'

There are prizes for the first bath and wardrobe to reach the island. Geering says, 'A lady farmer usually wins the wardrobe prize - she's developed a rapport with them. We also reward the most unlikely boat to stay the course. The first year it was won by a woman who sailed a mattress, decorated with tinsel and with a stuffed seagull at the top of the mast.'

Chris Geering's tips for newcomers are as follows: 'Keep your design simple. Gather your materials and make a rough plan of what you're going to do. But we don't want people bringing along wonderfully finished, ready- made boats. That would be against the spirit of the event.'

Build-a-Boat, Burnham Overy Staithe, near Burnham Market, Norfolk, today. Arrive by 9am, sail at 5pm. Cost pounds 5. Proceeds to sailing charities. Life-jackets compulsory. Info from Chris Geering (0328 738946)

(Photograph omitted)