DESIGN: AN IDEA WORTH LIVING IN

HOW WILL our homes look in 50 years time? Perhaps the conventional box-shape will be no more, replaced by pyramids, spheres, stars or ovoids. And maybe brick, stone, timber, concrete and steel will have gone the way of wattle and daub, replaced by new materials such as "smart" glass, plastic or holographic material. The answer, really, is anybody's guess. "If you want predictions, go to the fairground," is how the avant-garde French architect Jean Nouvel replies when pressed for his vision of the future.

But for many of his colleagues the temptation to gaze into a crystal ball and conjure up a brave new world is irresistible. There are competitions galore to design "the house of the future", and many others which concentrate on a particular aspect of the way we might one day live, most of them resulting in a combination of superb originality and stunningly daft hypotheses. In this realm, pointlessness and progressiveness often go hand in hand - but then that's no reason not to keep on trying.

The latest in a long line of experimental competition-winners is the Oyster House, a two-storey timber and laminate structure on a star-shaped deck, with a glass-walled, open-plan ground floor and flexible sleep/work/ play space upstairs. Designed by flamboyant British architect Nigel Coates, it will be built at next year's Ideal Home Exhibition, where its unconventional appearance is sure to make it a major attraction - though whether show- goers will actually want to live in it is another matter. "There may be outright hostility, but we hope not," says Coates. "We're hoping to generate considerable excitement. The house responds to how people want to use it and it has a womb-like quality with sensual curves. It's simple in construction, logical and very straightforward, and it also has a sufficiently strong character to enable people to identify with it."

Coates insists that this is not yet another attempt to create a futuristic home. The competition specified that entrants should "bring contemporary design solutions to a traditional British estate house", and the Oyster House uses currently available materials and techniques, sticking to the set budget of pounds 100,000. However, its cruciform shape, copper cladding and oval, upper-floor corner windows, not to mention its daring use of glass and unusual curving floors and ceilings, make it, quite clearly, decades ahead of the usual styles of spec-built houses by the likes of Wimpey and Barratt.

"While in one sense it appears very radical, especially in contrast to what's around at the moment, at the same time it is a functional proposal," says Simon Allford, the Royal Institute of British Architects assessor for the competition. "It is of its time, but could also become a house for the future. There is already a trend towards open-plan living, and I think the idea of the free ground floor is something that will occur, though maybe not in such a pure form."

Even further from your run-of-mill estate home are the three runners- up to the Oyster House. All of them demonstrate original thinking and an innovative use of technology, but are distinctly odd-looking - especially for those more familiar with the traditional Tudorbethan semi. There's the plug-in "Pacemaker" - Birds Portchmouth Russum's windowless fibreglass pod, which contains a kitchen, boiler and bathrooms and resembles nothing so much as a double-height industrial unit. There's Mark Fisher Architects' metal and glass capsule, which is raised off the ground to allow for garages and car routes beneath the streets, providing a utopia of pedestrian walkways and cycle paths. And then there's Made by Man's timber-boarded ecological house, with walls set at varying angles to maximise sunlight and reduce noise and wind, the concept incorporating a wind farm, solar barbecue, organic allotment, insulation made from recycled newspaper and a grass roof.

Futuristic or simply "for the future", the Oyster House may be just what's needed to restore the Ideal Home Exhibition's former reputation for cutting-edge home design. "The Oyster House looks extraordinary, arresting and exciting," says Michael Franks, managing director of DMG Exhibition's home interest division. "When the Exhibition started it was intended as a showcase for modern living. The Concept House competition takes the show back to its roots, giving the public a dynamic idea of what the contemporary house can look like."

The Exhibition's heyday was in the Fifties when, post-war building restrictions over, visionary concepts were not just commonplace but almost mandatory. The wackiest ideas were proposed in 1958 by German industrialist Dr Johann Ludowici: the Roof House, for cash-strapped first-time buyers, which consisted literally of a sloping roof with six rooms that could be hoisted up on top of an additional ground floor once the couple had saved up enough money to purchase it; and the Round House, an aluminium sphere designed to be an economic yet comfortable dwelling for workers in the remote Belgian Congo, but also suggested as an alternative shooting lodge or weekend retreat. Neither idea took off.

The most complete and serious attempt to predict the future, however, was in 1956, when radical young architects Peter and Alison Smithson were asked to come up with a House of the Future for the show's Village of Homes. They presented a design for living 25 years hence, with a one-bedroom town house arranged around a small internal garden. After entering via an electric folding front door, visitors passed through a curtain of warm air to remove dust and encountered a series of cave-like rooms, each different in size and shape. The translucent walls were made of plastic-impregnated plaster and the curved roof was covered with aluminium foil on a waterproof base.

It was intended that the house operated like a machine, with eye-level fittings in the kitchen, a sunken bath that filled to a thermostatically controlled temperature, a shower that both washed and dried, and a rise- and-fall table incorporated into the living-room floor. A single nylon sheet was all that was needed in the way of bedclothes, thanks to the controlled heating system, and the kitchen tap was turned on and off by a foot pedal.

Organically shaped storage niches and angular glass and Perspex chairs made the interior resemble something from the cult television series Lost in Space, but what was strangest about the house were its two "inhabitants", Anne and Peter, who wore "nylon casual" clothes designed by sportswear guru Teddy Tinling. Come 1981, not only were we not living in moulded plastic, push-button homes, but very few people saw pixie hats and crochet- look all-in-one bodysuits as the height of fashion. "The trouble with houses of the future," says Michael Franks, "is that when you look back they seem so silly. The problem is that if you can propose the idea, then what's the reason for not doing it now?"

In the Fifties it wasn't just architects who had grandiose notions about what the future would bring; the public, too, firmly believed that pods, pyramids and space bubbles were right around the corner. In 1957, 2 million people queued to see the Monsanto Chemical Company's House of the Future (this time, the future meant 1987) at Disneyland in California. A curving, starfish-shaped structure made of clip-together plastic sections, it featured built-in furniture, synthetic materials and yet more push-button commodities such as a retractable microwave and kitchen shelving, and it dazzled visitors with its flying saucer-like shape and tricksy gadgetry: "That's gonna take off " and "Where can I get one?" were, reportedly, frequent responses.

Come the Sixties, however, when technological innovation was slowing and "progressive" public housing design went so horribly wrong, the public's faith in the future was sorely shaken, despite brave attempts such as Cedric Price's Fun Palace and Archigram's plug-in cities - concepts of an alternative urban lifestyle that were unbuilt and, very likely, unbuildable. Then, in the Seventies, came the fuel crisis, and concept houses developed a serious predisposition to address the issues of energy-saving and environmental awareness. In April 1978, for example, Ideal Home magazine ran an article entitled "Tomorrow's Ideal Home", which envisaged pyramid- shaped homes with roof-mounted windmills, solar panels, water meters and tiny windows to minimise heat loss. "Each house will be required to generate a proportion of its own power in the house or in the garden," writes the author. "On blustery days, windmills can do some of the work; on sunny days, solar collectors take over. Heat exchangers can be sunk into the ground and those who have running water nearby can install a water wheel."

"Could this prize-winning energy-saving solar house prove to be a prototype for new urban communities?" asked House & Garden in March 1979, describing a design by Sheffield University's Department of Architecture for an "ecotecture" house with high insulation, a turfed roof and the ability to recycle water for washing. What made the house look strikingly different and rather beautiful were its huge, sloping glass walls that were the key to a complex solar heating system.

Two years later, at the ground-breaking Milton Keynes HomeWorld exhibition, enormous glass walls again featured prominently in the quest for energy consciousness. The A-shaped Solar House was the most imaginative answer, with a double-height conservatory open to the main living areas and the bedrooms. A plant-covered timber pergola was intended to reduce overheating in the summer, while solar panels would boost the domestic hot water supply. Two other houses, the Future Home 2000 and the Lead Harvester, also featured double-height conservatories, though not in such an unusually shaped construction, while further offerings included yet more pyramid and A-framed houses, including an extendible home which could be enlarged with the removal of plywood side gables, and a tiny single storey home with an entrance door that was described at the time as being so huge it would look more appropriate on the front of the White House.

Again, none of these designs have been adopted by major housebuilders, and one would be entitled to wonder just what all the fuss was about. Is there any point in the concept house?

Architects insist there is. "All innovative design is dateable," says Nigel Coates. "Some Milton Keynes housing is incredibly dated because they were one-shot varieties that didn't create continuity. The energy movement in the Seventies wasn't taken on board because it was fanatical and produced ugly buildings. But today a lot of people have started to look at the potential of the house again and we are going to see a surge in new ideas." Simon Allford agrees. "Like any type of speculative, one- off design, a lot of the spin-offs from these concept houses come in other ways," he says. "Even though not everything will happen exactly as predicted, such ideas provoke discussion and things filter through. You have to do something dramatic and go to extremes in order to kick-start attitudes. These things are like manifestos. You inevitably get differences between what happens in the future and what was suggested, but that's a positive thing because it suggests to people that the ideas are worth pushing."

The spin-offs from the Seventies homes of the future have been numerous, if not immediately obvious. The energy-saving experiments at Milton Keynes' HomeWorld led directly to another show, Energy World, in 1986, in which the houses were all given an efficiency rating. This, explains Dr Eva Chapman, director of National Energy Services (the business arm of the National Energy Foundation), in turn led to the recent introduction of building regulations which require all new homes to be given an energy rating. "It's actually very hard to build an inefficient house now, and it's all thanks to HomeWorld," she says. "There were problems - two-storey conservatories were too hot in summer and didn't always give people the privacy they wanted, but the idea has come through in terms of larger windows and conservatories being added to houses. Solar panels have been incorporated into programmes now, heat exchangers are widespread and most builders use low-emissivity glass. The idea of selling excess electricity generated by alternative sources, as used in the Future Home 2000, is just starting to take off."

And what of Anne and Peter? Although we're not living in their House of the Future, the Smithsons did make some pretty accurate suggestions for the home of 1981, including the microwave oven, remote-controlled colour television, entryphone system and answering machine. Neither wholly accurate nor totally inaccurate, such visions, concepts, experiments, are, at worst, harmless and entertaining, and at best innovative and capable of encouraging technological and educative advances. It remains to be seen whether Coates' Oyster House will fulfil its potential as a reinvention of the estate house. Only time - or perhaps Mystic Meg - can tell.

An exhibition of the designs for the Oyster House, together with nine other entries shortlisted for the Concept House 98 competition and the three runners-up, will be held at the Architecture Foundation, 30 Bury Street, London SW1, from 4 March. Tel 0171 839 9389 for details. The Ideal Home Exhibition opens at Earls Court on 19 March and runs until 13 April. Peter and Alison Smithson's radical 1956 town-house (above), with its gadgets and nylon-clad inhabitants

1958 Round House (above), designed for workers in the Belgian Congo: 1980 prototype Milton Keynes house (left)