Ralph Carpenter and his wife, Jenny, live in Britain’s first home built from wacky baccy or, as they prefer to call it, cannabis hemp.
They have endured the builders’ jokes of “Isn’t it going to go up in smoke?” and teenage jibes of “Can we see the wall joints?” but now they’re having the last laugh. Top-o’the-hill, near Sudbury in Suffolk, is warm, dry, stunningly good-looking and a test-bed for what Carpenter, an architect with the firm Modece, hopes will be the “green” housing of the future.
“We lead a double life, as the house is actually split in two: one half is original, 17th-century, brick-and-timber built, the other is our 21st-century hemp-and-timber home,” he explains.
Indeed, they could not be more contrasting: from the olde-worlde style of the brick side, with its wood-burning stove, deep-seated sofas, rugs and throws, you are thrown into the brightness and light of the modern wing, which has large, airy spaces in minimalist style, deep windows, solar panels, colourful floor-to-ceiling curtains, a bed, a piano and little else.
It was in 1985 that the couple and their two children, Nicholas and Frances, first moved to what was then a three-up, three-down silk-weaver’s cottage.
“A surveyor would have told us not to go anywhere near this place; superficially it appeared habitable, but everything just crumbled when touched. The Victorians had messed it up, cladding the original 17th- century frame with bricks that caused permanent damp and woodworm over the years,” says Carpenter.
Undaunted, they stripped it down to its wooden frame and rebuilt it “because in 1985 there were no alternatives”.
But as his interest in green lifestyles grew, so did the family’s need for more space.
The crunch came when the Carpenters inherited a Steinway grand piano. “It gave us the excuse we needed to expand and build in hemp. The non-narcotic variety, of course,” he says.
“By coincidence, a year earlier I’d been introduced to a crazy French lady who bought and treated raw hemp and I’d visited clusters of hemp houses in Normandy and Brittany, some built in the late 1980s. In France they’re way ahead of us, they’ve fewer planning rules and building regulations.”
Carpenter says hemp is an ideal crop “because it matures in four months, needs no pesticides, returns nutrients to the soil and has a high yield”.
Keen to introduce it as an alternative building material in this country, he got together with The Housing Corporation, St Edmundsbury borough council and Suffolk Housing Society and set up a project to construct two two-bedroom semi-detached homes entirely from cannabis hemp.
“In the meantime, while getting this housing project off the ground, Jenny and I have been the real guinea pigs, building our own half-home from hemp. We’re living proof that, yes, it works.”
Planning permission to double the size of their existing house was given without question (“they agreed it was organic growth”). Building regulations were more of an issue but were eventually passed thanks to support from an official who understood that working with cannabis hemp simply meant a return to traditional building methods.
The greatest hurdle was finding a builder willing and able to work with a rather unusual material. “We ended up using two: the first to put in the brick plinth and lime mortar foundations; the second to see the project through. He didn’t quite know what to think when the 500 bags of cannabis hemp arrived by lorry, though in its raw state it could pass for chopped straw.”
Mixed with lime and water to a porridge-like consistency, then poured between ply shuttering frames and left to set, the hemp walls and floors took two months to put in and another six weeks to dry, to an appearance akin to Weetabix.
“By that time, thankfully, the jokes about smoking had begun to dry up too,” recalls Carpenter.
To finish, the walls were given a coat of ochre-coloured limewash on the exterior, and left natural, limewashed or covered in plasterboard on the interior. Not a drop of cement has been used.
“Cement uses huge quantities of energy in its production; the housebuilding industry could, if it chose, survive without it,” says Carpenter.
“Cement starts to disintegrate after 28 days, whereas a hemp and lime mix strengthens because lime absorbs the carbon dioxide in the atmosphere as it sets.”
The Carpenters have lived in their hemp home for four years now. The extension has provided a music room, an extra bedroom and an en-suite bathroom on the first floor, and a ground-floor workshop, double garage and storage rooms.
“It’s everything we’d hoped: it needs far less heating than the old house, there’s no condensation, it’s sound-absorbent and it doesn’t shrink, so you don’t have to keep filling in the cracks,” says Carpenter.
“After all, hemp is not new. Until the middle of the 18th century, it was Britain’s largest agricultural crop. We made clothes from it, writing material, ships’ sails even.”
And the modern-day cost of their home? “About £70,000 — £800 per sq m — much the same as using traditional materials.”
The Suffolk housing project was completed in December 2001, and its two homes are being closely monitored for energy performance. Carpenter has more hemp projects planned for East Anglia.
A hemp home may have no hallucinatory qualities but these owners are quietly ecstatic.
For more information, contact:
88-89 St. Johns Street
Bury St. Edmunds
Tel: 01284 761 141
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