The appeal of Channel 4’s original Grand Designs programme – still just discernible amid the remarkable welter of spin-off activities now forming the franchise – was simple. Ambitiously naive people set out to build their own homes, suffered trouble and strife along the way, but eventually moved in and declared themselves delighted, if impoverished. We all imagined ourselves doing the same. Yes, you can break free from the clammy grip of the mass-market housebuilders. You can build your own dream home, be the envy of all your friends and live happily ever after.

The Grand Designs bandwagon rolls ever onwards. Its presenter, Kevin McCloud, is now a niche developer, filming himself as he builds tasty little estates in Swindon through his company Hab (Happiness, Architecture, Beauty). Last week, he blamed his own programme for the rash of “me too” one-off modernist white-box houses now being built – once fashionable, now a cliché.

Britain’s biggest mass-market housebuilder, Persimmon, meanwhile, has announced a moratorium on new building sites until market conditions improve. Sales are plummeting because of the shortage of mortgages, and of course all the main housebuilders are in much the same boat. We know this, but is something else going on?

Look at the shortlist for this year’s Grand Designs Home of the Year competition, which, for the first time, will be shown in a week-long television extravaganza, starting tonight, with viewers given the chance to select the winner. These aren’t the best houses I’ve ever seen, but they are good, individual and varied, with, McCloud will be pleased to hear, not a white-box cliché among them. They have been built all over the place: on impossibly tight scraps of city land, in suburbs, in woodland, on islands.

Whether new-builds or conversions, they mostly share an open-plan, modernist look. They like expensive sliding-glass walls, often with timber cladding. They are big on framing views. There are also out-and-out eco-homes, the sort made of lime-rendered straw bales and sheep’s-wool insulation. Just possibly, the market is telling the mass housebuilders something: could we have homes that are a lot less humdrum, please?

Okay, so ambitious individualism isn’t the only model. There are a lot of self-builders out there, people who find a plot of land and fling up a kit home that looks remarkably like the sort of thing the big housebuilders produce. There are magazines stuffed with examples to make the fastidious shudder – fine if that’s what you want. The niche market for adventurous, architect-designed homes, however, is growing apace. Fifteen or 20 years ago, few good one-off homes were being constructed.

Today, they’re being built all over the place. However influential, Grand Designs didn’t start this movement, it just exploited it.

Even the mass housebuilders are beginning – slowly – to take notice. Why else would Wimpey Homes employ Wayne Hemingway, the former fashion designer, to impart a touch of glamour to its new estates? When times are tough, you need something that distinguishes your product from the rest of the stuff out there. So, the big boys of housebuilding might be able to learn something from the shortlist – such as using better, eco-conscious designers.

Several of the homes are designed by architects for themselves. Take Marcus Lee and his family, who live in Hackney, east London. Lee used to work for Richard Rogers – he spent 11 years on Terminal 5, which might have been why he left – and now runs his own successful firm. For his own house, he went for a low-energy timber-framed system.

Having bought a plot of land at the end of a lane for £85,000 in 2000, he finally got round to creating the Frame House, as it is known, in 2005. It cost £300,000 and took just four months to build, though Lee admits it wasn’t quite finished. “We needed to move in quickly, so we camped on the upper floors. It’s only just finished now, really.” Lee, his wife, Rachel, and their daughters – Ruby, 10, Jodie, 8, and Mae, 6 – have found the house adaptable. At first, the girls were together in one big bedroom, but the house was designed to convert into smaller private bedrooms when required.

This is an update of an ancient way of building – medieval farmers knew all about timber-framed construction, using solid oak. Lee went for laminated larch beams, filling in the walls with wattle and daub. He used high-insulation, compressed wood fibreboard, then added to his eco-credentials by heating the house with a wood-pellet boiler. Originally, it was going to be a flat-roofed two-storey house, but then Lee thought, why not have the equivalent of an attic to convert? So he added a mono-pitched roof, gaining a long, triangular-section third floor.

With its views out across neighbouring gardens, plenty of natural light and spacious, slate-floored ground-level living areas, the result is something of a city oasis – and emphatically not a white modernist box. Hurrah.

Luke Tozer, another architect, applied his ingenuity to a house built in a gap only 8ft wide – in what was once an alley in Maida Vale, west London. Hence its name, the Gap House. “It’s the sort of site only an architect would take on, because of the difficulties,” Tozer says.

With listed buildings on either side, initially sceptical neighbours and no planning permission, Tozer was taking a big risk when he and his wife, Charlotte, bought the site in 2005. He got his permission, however, demolished the cottage, filled the alley with a slender four-storey tower and made the most of the space where it widens out to 24ft at the back. With ground-source heat pumps and good insulation, the four-bedroom, low-energy house cost about £600,000 to build, but the Tozers, both 37, with two young children, are in it for the long term. “We intend to be here for 18 or 20 years,” he says confidently.

If you think that’s ecofriendly, it’s nothing compared with Penwhilwr, Rachel Shiamh’s two-storey, lime-rendered straw-bale house in an acre of woodland in Pembrokeshire. This is a self-sustaining, off-grid home that generates its own power from solar panels and a wind turbine – although Shiamh, 42, a former dancer, allows herself a little bottled gas to supplement her woodburning stove for cooking. She bought the site in 1996 for just £5,000, later moving into a hut there when a family legacy meant she could build the house. She moved in less than a year ago. It cost just £70,000, thanks to an army of volunteer helpers.

Shiamh now lives alone (with dogs and cats), but the house is always busy, as she uses it to teach green building techniques. Nor, despite the materials with which it is built, is it temporary – it is intended to last about 150 years. “It has turned out totally beyond my expectations,” she says. “Straw-bale houses are warm and the lime walls are breathable. With one good-sized woodburning stove, I can heat 2½ storeys.” As she grows the wood she burns, as well as a lot of her own food, Shiamh is indeed touching the earth lightly.

And no, we wouldn’t expect Persimmon Homes or its rivals to build estates full of houses like this. It is simply the most extreme example of the eco tendency in housebuilding, with individual designers and builders leading the way. If more people like the idea of one-off houses, full of good ideas, maybe it’s time to look again at the system of building sterile estates with needlessly wide roads and double garages. Maybe, in the end, we just want a real choice of better alternatives.

www.channel4.com/4homes

The grandstand

This year’s Grand Designs Home of the Year competition is in five categories: Best New Build, Best Eco Home, Best Redesign, Best Conversion and Best Restoration. The three properties shortlisted for each category will be shown on Grand Designs Live, starting tonight at 8.05pm on Channel 4 and continuing from Monday to Friday at 9pm. Viewers will have the chance to vote for their favourite, and an overall winner will be chosen on Friday.

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