Tucked in the corner of a garden in the town of Frome, Somerset, stands a little tower with a conical roof topped with a pineapple. This flamboyant finial, like the rest of the folly, is the work of the talented and resourceful Nigel Day: the uppermost leaves started life as a copper hot water cylinder.

Day has lived in this quiet Frome street for around three decades, during which time he has renovated and extended a rundown cottage. Carvings, inscriptions, secret doors and a clock tower are all his own work, and somehow he has also found time to build a folly.

He took some time to decide on the form this folly would take, knowing only that he wanted it to feature a terracotta scallop shell which he had picked up in a reclamation yard many years earlier. Abandoning the idea of a sham castle or an obelisk, he decided on a circular tower, with the shell as an overdoor, and work began in 2006.

Everything was built to meet the building regulations of the day: the footings go down about five or six feet. Such is Day’s attention to detail that each of the trapezium-shaped roof tiles was cut by hand: this job alone took four weeks. Day’s son helped get the reconstituted Bath stone blocks into place, but otherwise he executed all of the work himself – apart from the handsome metal gates which were made to his design by a local blacksmith. Day even carved the iguana which basks on the outer wall.

With the exterior complete Day needed a little help from his friends. They were recruited for the onerous task of banqueting on scallops and crab (washed down with plenty of Muscadet) to provide materials for the interior decoration. With additional shells purchased from a specialist supplier, Day set to work creating the shellwork, which depicts the circle of life in the sea.  This idea was inspired by John Steinbeck’s The Log from the Sea of Cortez, in which the author realises that there is no such thing as an old fish: everything in the oceans is eaten by another creature.

Shellfish also appear on the tiled floor, which Day designed and painted himself and fired in a borrowed kiln. Day’s favourite books are Lewis Carroll’s Alice in Wonderland and Alice Through the Looking Glass, and he continued the shellfish theme by featuring the poem of The Walrus and the Carpenter, in which the little oysters are tricked into becoming lunch.

Day has enjoyed his folly now for fifteen years but has two regrets. One is that the bats which initially seemed interested in roosting in the roof-space have never settled in, and the second is that he wishes he had created a hollow tube up through the roof, through which he could have launched rockets on fireworks night.

Day remains full of ideas, and it is very unlikely that this is a garden that will ever stand still. The garden is private, but opens occasionally for charity.

Thanks to Nigel for a warm welcome, and to he and Paul Salter for help with photographs. The Folly Flâneuse visited on a bleak day – main pic – and didn’t get to enjoy the summerhouse in the sunshine.

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