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Straw houses could help to cut carbon emissions – and new research proves that they won't blow down

Building his house of straw didn't do the first little pig any favours, but a modern take on straw-bale construction may well be the grand design of the future if results coming out of the University of Bath are accepted by the construction industry.

Think of a straw-bale house and you might imagine a tumbledown shack that leaks, creaks, slumps and smells somewhat of the farmyard. But step into BaleHaus, a startlingly contemporary looking prototype home that has been built on the Bath campus, and there's nary a wisp of straw to be seen. Instead, you're in the hallway of an upside-down house with two bedrooms and a bathroom on the ground floor, and an airy open-plan living area upstairs. It feels like a little piece of Scandinavia has just arrived in Somerset.

The straw bales, it turns out, are all packed tightly inside a series of prefabricated rectangular wooden wall frames, which are then lime-rendered, dried and finally slotted together like giant Lego pieces, called ModCell panels.

The problem with straw houses, it seems, isn't that they don't work, but that people perceive them as being a bit hippy and not particularly durable. Add to that the problems of getting a mortgage – very few lenders will consider straw-bale construction – and it's hardly surprising that most homes in the UK are still built of either brick or stone.

The benefits of straw, points out Professor Peter Walker, director of the University of Bath's BRE Centre for Innovative Construction Materials, are that "it's cheap, widely available and a good insulator. It's been used in building houses for hundreds of years."

As a by-product of an industry that exists all over the world – the stalks that remain after grain has been harvested – straw also helpfully soaks up carbon from the atmosphere and locks it in, so long as it is not allowed to decompose. For the building industry, which currently depends on materials with very high embedded energy costs – concrete and brick are expensive in carbon terms both to make and to transport – straw could therefore offer a welcome solution to housing's greenhouse gas emissions.

However stylishly modern your environmentally friendly straw-bale house may look, however, you still want to know that it won't get sopping wet in a thunderstorm or go up in a whoosh of flames if you knock over a candle. The results now being published by Walker and his research partner, Dr Katharine Beadle, who have spent the last 18 months testing the BaleHaus against an exhaustive list of risk factors that could rot it, burn it or blow it down, so far seem to be reassuring.

"You always want a bit of drama, but we didn't get it!" laughs Beadle of the day the team took a ModCell unit to a test laboratory and tried to reduce it to ashes by strapping it to a fiery furnace and raising the temperature to over 1,000C.

"It's a standard test to replicate a fire in a building," explains Walker.

"You want a minimum of 30 minutes' resistance; that means you know that a house will at least retain its structural integrity for half an hour, which gives people a chance to get out."

It took an hour-and-a-half of being in direct contact with the flames, says Beadle, before the lime render began to drop off, "and then the straw did start to burn back, but because it's so compacted it suffered more charring than actual disintegration."

After waiting another 45 minutes and finding that the panel still hadn't failed, the team gave up and stopped the experiment, secure in the knowledge that the material had performed way beyond the requirements of building regulations.

When it came to blowing the house down – hydraulic jacks were placed against the walls to replicate wind forces pushing against the bales – the ModCell panels moved a few millimetres, but stayed within the tolerances allowed for by the computer modelling carried out prior to its construction.

That, says Walker, could be very good news for the price of the eventual ModCell building system.

"It means the house is stiffer than it needs to be, so we now have the option of taking away some of that stiffness – ie, reduce its internal timber – and that could reduce the cost."

The approximate cost of the current modular building system for this design is £132,000 from above the concrete slab. For a smallish two-bedroomed house with one large open-plan kitchen/diner, that doesn't seem particularly cheap given that straw is supposed to be inexpensive, and you'd still have to buy the plot and dig the foundations.

"Cost is a challenge to the introduction of this technology, but as a prototype house I think it stacks up well," says Walker.

"The aspiration is that it should be cost-competitive, with more savings coming through reduced heating bills."

To replicate the heat given off by humans and appliances, arrays of incandescent lightbulbs on timers blaze in every room at pre-programmed times of day "to see how much heat escapes, and what level of heating would be needed at different times of year," explains Beadle.

"That environmental modelling will give us all the numbers about the energy the house is predicted to use. And if we are predicting how it will operate given climate change, we can then put in those variables."

Sensors embedded within each wall panel constantly monitor the degree of moisture absorbed and then released back through the breathable lime render into the air outside by the panels. And on the airtightness test that was carried out, BaleHaus came in way under the building regulations threshold, and did considerably better than the far lower "best practice" standard.

Next up is going to be the flood test. Disappointingly, the researchers aren't simply going to leave the bath taps running: instead, they'll stand a panel in a metre of water, measure how long it takes to dry out and assess whether using industrial dryers causes damage to the straw.

"Longer term, we'd like to maybe get some people to live in it, a family of three or four perhaps, and see how it performs in a real-life situation," says Walker.

Student accommodation, I wonder? Walker suddenly looks a bit concerned for his straw-bale baby, so probably only mature, well-behaved responsible students who will promise no rampaging house parties should apply. But who knows when the first straw-bale halls of residence will be built for students desperate for some decent, earth-friendly and thermally efficient digs?bre

Elephant and Castle's Strata has dramatically changed the south London skyline – and the integrated turbines are a world first

It is the world's first skyscraper with built-in wind turbines. But is London's Strata a green gimmick – or the future? Jonathan Glancey takes to the skies

I am standing on the wind-buffeted tip of the Strata tower, looking out through the blades of what appear to be an enormous propeller, at the London skyline and the green basin beyond. St Paul's cathedral, across the river, seems close enough to touch. It's the kind of view, and the kind of heroically stylised building, you would expect to see in some 1930s sci-fi movie: the perfect place for a hero and a villain to have a rooftop showdown.

At 147 metres, the newly opened Strata is London's tallest residential building. The nine-metre blades I'm standing beneath are housed in one of three wind turbines that crown this new tower soaring above Elephant and Castle, an area of the city not known for flashy penthouses. But Elephant and Castle is undergoing a massive, if slow, transition from a rundown miasma of noisy road intersections, underpasses and vast housing estates into what the Borough of Southwark hopes will be a £1.5bn model of inner-city regeneration.

The plan was first made public six years ago and work is unlikely to be completed before 2020. It's a colossal challenge, as well as an opportunity, and the £113.5m Strata, the first of three skyscrapers planned for here, is a symbol of the dynamism and energy the project demands. And that energy must, of course, be seen to be green. It's early days, but if the turbines work as planned, and aren't too noisy for residents in the pricey penthouses beneath them, they should generate 8% of this 43-storey building's energy needs. This is roughly enough to run its electrical and mechanical services (including three express lifts and automated window-cleaning rigs) as well as the lighting, heating and ventilation of its public spaces, which include an underground car and cycle park.

Strata is the first building in the world to incorporate wind turbines into its structure. Yes, the new Bahrain World Trade Centre in Manama, by the firm Atkins, also boasts three giant turbines, but these are set on steel struts connecting its twin towers, not part of the actual towers themselves. While I can vouch for the strength of the south-westerlies that will turn Strata's blades, whether its turbines will set a precedent for future British towers is less clear: this rooftop was exceedingly hard to construct, almost prohibitively so, every part of it having to be hauled up.

However, what the three fans do, without a doubt, is give Strata a striking profile. Whether you find this exciting, disturbing or simply over-the-top will be down to personal taste, yet it's no surprise the tower has been dubbed the Electric Razor, not just because of its whirling blades but also because of its black and silver lines that seem to pixellate upwards; Boris Johnson, Mayor of London, has called it the Lipstick.

So what do green experts think? "You've got to take your hat off to the design team for delivering a building that captures the imagination," says Paul King, head of the UK Green Building Council. "I doubt wind power will become a common feature in high-rise inner city projects, but without this type of bold innovation, how would we ever know? Developments like this show that sustainability is increasingly becoming mainstream. That's something everyone should celebrate."

Including the 1,000 or so people who have already moved into – or bought into – Strata's 408 flats (each boasting floor-to-ceiling windows). And there is a difference between the two. Nearly every flat was bought off-plan, before construction began, 50-75% of them by investors. This is a shame: the whole idea of the tower is that it should be a guiding light for new inner-city residential development. This is meant to be a home for local people, not a machine for property market profiteering.

Indeed, 25% of the flats, on floors two to 10, are "affordable homes", for those on incomes of less than £60,000 (in central London that kind of money won't guarantee a home of your own); meanwhile, a three-floor pavilion to the side of the tower has been given to council residents leaving the soon-to-be-demolished Aylesbury Estate, a 1960s housing complex seen by most as an enormous failure. Tony Blair made his first speech as prime minister at this estate, in a bid to show his government would care for the poorest elements in society.

To my mind, Strata's big propellers give the building the feel of an airship holding aloft the passenger cabins (or flats) below. Or perhaps it's more like an old-fashioned transatlantic liner with its complement of first-, second-and third-class passengers. I think of this as architect Ian Bogle, of London-based BFLS (formerly Hamiltons Architects), leads me through the tall, narrow lobby to the lifts that shoot silently up to the residential floors.

'You feel like you own the city'

The views are spectacular. Most front doors open directly onto gaping vistas of London, framed by giant windows. They are not for the faint-hearted. Bogle goes to open what looks like a door at the side of a window and I think he might vanish into the ether. As it happens, he's simply opening a perforated screen designed to let fresh air in. "We've tried to get as much daylight and fresh air as possible into the flats," says Bogle. "You certainly feel as if you own the entire city from up here."

Indeed you do. There are magic moments, too: way below, trains race in and out of buildings and seem to pass through the tower itself. It reminds me of the super-modern city drawn by Antonio Sant'Elia, the Italian futurist architect, shortly before the first world war. His Città Nuova was a dynamic, machine-like metropolis through which cars and even aircraft would pass, via openings in the buildings. His imaginings inspired film-makers, from William Cameron Menzie's Things to Come in 1936, to Ridley Scott's Blade Runner in 1982; they also resonated in city developments as dramatic and diverse as the Barbican, the Pompidou and the Hong Kong and Shanghai Bank. And they echo today in these views from the Strata tower, and in its mighty turbines.

But are they just a tokenistic green gimmick? Or will they propel us towards a new urban architecture, one that's cinematically thrilling and ecologically sound? Until its sibling towers rise and the redevelopment of Elephant and Castle is complete, it will be hard to properly judge Strata. Right now, it stands alone, a sleek silver sentinel, towering over the follies of the recent past.

A new building at a centre devoted to eco awareness is more than just a checklist of green materials and practices. It is also a triumph of modernism and minimalism

It's not often that you judge a new building by its smell, but here you sniff the place like a sommelier: old barn, straw, notes of cedar and cow dung, must, something faintly citric. Nothing like the usual pong of new carpet and plastic paint.

This is because the building in question, the Wales Institute for Sustainable Education (Wise), is trying as hard as it can to use natural building materials – "Basically plants and earth," to quote one of its architects, Pat Borer. Also animals, as in addition to a timber frame, rammed earth walls and a coating of lime and hemp, it uses sheep's wool for thermal insulation.

It is designed by two architects in collaboration, Borer and David Lea. Wise is part of Cat, the Centre for Alternative Technology, which, once you've got past its irritating way with acronyms, is an impressively persistent organisation. It is a product of the first great wave of eco-awareness, in the 1970s, when no one had heard of global warming, but a lot of people were worried that oil was running out. There was also a general feeling that mankind was ravaging the Earth and that this couldn't be a good thing.

Cat was founded by the old Etonian Gerard Morgan-Grenville, with the vague-seeming aim to "show the nature of the problem and show ways of going forward". It was located in an old slate quarry halfway up a steep hill near Machynlleth, in a remote part of mid-Wales, almost where the land runs out into Cardigan Bay. Over the years, Cat built prototypes for ecological ways of living: a building made of straw bales, wind turbines, the filtering of sewage through reed beds until it becomes almost-clean water. School parties and visiting groups of Chinese and Africans now roam the site.

Most of the site has a ramshackle and ad-hoc air. There are still DIY solar heaters, made of radiators painted black to absorb heat and placed under glass, from 30 or so years ago. There is the broken blade of an ex-wind turbine. You can ascend the steep hillside to the centre by way of a lift powered by water from a high-up reservoir. "It is truly zero-emission transport," says Borer. "It runs on rain," he adds, amid light drizzle on a day when the rest of Britain is washed by a heatwave. "What could be better?"

The site is powered by solar power, a boiler burning wood chips and wind turbines. It is connected to the national grid, to which it gives a surplus of electricity. The centre stays true to its co-operative origins: all staff, whatever their status, earn between £13,000 and £16,000 a year, except for those on academic pay scales. Wales was a refuge of choice for hippies escaping the big city, but this work of 1970s dreaminess has shown staying power.

Its £4.5m new building takes it to a new level of ambition and seriousness, but misadventures during the building process almost caused it to close. Its main purpose is to provide courses for masters students, so it has an auditorium, seminar rooms, bedrooms and a bar.

Clearly, the building has to practise what the centre preaches. Many in the world of sustainable design like to pick holes in another's work, to point out which of the panoply of interconnected issues a given project has failed to address – what materials, where they come from, what energy was used in their transport, what will happen to them after demolition. Cat has exhaustively logged every aspect of its building, including each journey made to and from the site, and has made the data the subject of a research project. As green building is still an inexact science, Cat wants to know what works and what doesn't.

The energy used in building is as important as that used once it is built. According to Borer, who was once on the staff of Cat before he set up his own practice, "a 'zero-energy' house can use 30 years' worth of energy to build" because it uses materials such as steel, concrete and plastic. At Wise, they have used thick walls of rammed earth and avoided PVC, an especially energy-intensive material, in pipes and electrical insulation. They use durable woods such as oak and larch, because lesser timbers need to be treated with toxic chemicals and therefore become toxic waste when they are disposed of. The building does use aluminium, a taboo material for some green builders, but sparingly. "We use it for its wonderful properties, like its strength. We wouldn't use it for things like ceiling tiles, where you could just as well use another material."

But the issue for sustainable architecture, beyond whether it actually works, is whether it is architecture. Is it, in other words, just a checklist of materials and techniques, bound together by some calculations, or does it give its own quality to the way built spaces look and feel? By this, I don't mean it has to wear its greenness on its sleeve, that it has to festoon itself with flapping windmills and turf roofs to prove its credentials.

Here, the less talkative of the two Wise architects comes into his own. David Lea, bearded and quietly spoken, looks every inch an architect who has spent the past four decades in rural seclusion. With his interest in natural materials, local to a building's site, he has sometimes been ploughing a solitary furrow. He received the equivocal honour of being praised by Prince Charles for a building he did for student farmers in Cirencester, Gloucestershire. His best-known work is a tiny house for an artist, of mud and thatch, that looked like an upturned boat.

He studied, however, under Leslie Martin, one of the architects of the Royal Festival Hall, and Lea is not some wizard of the Celtic fringe or purveyor of mud huts for hobbits. His building is poised and spare, in the manner of some of the best modernist architecture. It adapts cleverly to the site's rollercoaster terrain, creating multiple levels out of its ups and downs.

It also turns, in several directions, to face the abundant nature around it. One space is oriented towards a distant view of mountains and an access gallery runs past an impressive cliff of slate. A courtyard collects all the rain into pools. A big bay window catches views in several directions. It's simple stuff, but a lot of architects wouldn't bother with such things and it's nicely done. It creates a rapport with nature that does not have any measurable effect on CO2 emissions, but is surely a necessary part of the ethos of being green.

It could have been built of concrete and steel and almost felt the same, but only almost. The choice of materials subtly changes the feel of the place, as well as its carbon footprint. There's that smell, but also a different touch and acoustic. It's not spectacular, or fanatical, but it shows one way of doing sustainable architecture in the fullest sense: not just a pile of box-ticking, but making spaces.

Salford University staff to simulate life in terraced two-up, two-down in effort to make UK's housing stock greener

Energy-efficiency scientists are to study how people live by rebuilding an entire, redbrick Manchester terraced house inside a university laboratory's sealed testing chamber.

The two-up, two-down dwelling is identical to those portrayed in Coronation Street, television's oldest surviving soap, and to more than two million real-life homes.

It will be used for power-saving experiments in simulated climates featuring high winds, snow and Manchester's notorious rain.

The pre-first world war house is to be salvaged from a nearby demolition scheme. It will be dismantled within the next fortnight and rebuilt in the Energy Hub at Salford University.

Gas, water and electricity will be piped in and furniture installed, with staff from 13 academic departments taking turns to play the part of residents.

Life in this "Energy House" will be as busy as in any of the terraces which sprang up across the North of England to house those working in mines and mills, but focused on entirely modern concepts such as carbon-reduction equipment and smart-meter tests.

Psychologists will join engineers in a series of experiments to see if particular wall or carpet colours make people feel warmer and reduce the demand for heat. Home energy use accounts for 30% of the UK's greenhouse gas emissions.

"It's a house from the past, working for the future," said Dr Nigel Mellors, associate dean of science, engineering and technology at Salford and one of the team running a project aimed to last 20 years or more.

"But this one is only the beginning'" he said. "We reckon we'll know everything we need to about how to improve a terrace like this after about three years. Then we'll knock it down and build something different. Perhaps a typical 1960s house, to see how that can be improved."

The project is designed to parallel work on new-build energy-saving homes, recognising that many housebuyers prefer older properties for other reasons.

Dave Ritter, sustainability director at BDP architects, who are also involved with the scheme, said the sheer number of surviving terraces was proof of their appeal.

"They are in many ways an extremely successful design, with a particularly good sense of community and neighbourly links," he said.

"They are on a nice scale and sensibly laid-out inside. But energy-saving was not an issue at the time they were built, and this project is an imaginative and very practical way of putting that right."

Remodelled terraces have already proved a success in the Lancashire Pennine towns of Nelson and Colne and also in Salford, notably at Chimney Pot Park where the developers Urban Splash have "upended" the old model, giving 19th century terraces sleeping quarters downstairs and living rooms on the first floor.

Leeds has found a huge market as starter homes for its 40,000-plus back-to-back terraces, once condemned as slums for having inadequate ventilation but now, with three of their four walls comfortably sandwiched by other homes, praised for saving heat and economical use of space.

Green variations also include some Northern towns' policy of "alternate demolition", where the clearing of every other row of barrack-like terraces has doubled the gardens and open space of those left.

Larger scale demolition of traditional terraces by government housing renewal projects has caused anger in Liverpool, Manchester and Lancashire's former milltowns.

Professor Steve Donnelly from Salford's faculty of science said terraced houses had won their case for reprieve but now needed "ways of being more efficient, as they are going to house people for generations to come. That requires detailed and robust research, which the Energy House will provide".

Tony Juniper, former director of Friends of the Earth, said: "Domestic energy use accounts for a huge proportion of emissions which we have to reduce. The millions of real-life terrace houses like this one are going to play an important part."

John Alker, policy director at the UK Green Building Council, said: "This looks like a great piece of research and it will be particularly interesting to see the results on behaviour, where less has been done to date.

"But let's not forget that there is a hell of lot that we know already – the biggest barrier to low carbon home refurbishment going mainstream has tended to be the upfront cost to consumers, and that is set to be tackled by the Energy Bill in the form of 'Pay As You Save schemes'."

The Manchester United football star plans to build an eco-home which closely resembles that of the Teletubbies . . .

Manchester United star Gary Neville has revealed plans to build an underground "eco-bunker" (above) at his home in Lancashire. Locals have already dubbed it Teletubbyland (top). Artists' impressions of the £8m zero-carbon development, designed to merge seamlessly with the surrounding moorland, resemble something between a futuristic hobbit hole and the hideout of a rural Bond villain. The architects, meanwhile, have compared it with Skara Brae, a neolithic settlement in Orkney. Whatever inspired this hillside hideaway, its similarity to the Teletubby residence is hard to deny. Rumours of a plan to build a vacuum-cleaning dog named Noo-Noo are so far unconfirmed.

An engineering firm reckons that rebuilding the palace could make Her Majesty much greener. But why stop there?

A nefarious plot to destroy Buckingham Palace has been exposed, but it's not the work of terrorists, anarchists or extremist property developers. No, this one comes from an engineering consultancy. Before the capital goes on high alert, Atkins, a design and engineering group, weren't actually intending to carry out this plan. In a none-too-serious assessment of the building's green credentials, rather, they dropped the hint – or was it a gauntlet? – that the Queen might be better off with a new London eco-crib.

Atkins's proposal was part of a fanciful survey by Construction Manager magazine into how much it might cost to rebuild British landmarks. It concluded that you could build a new energy-efficient replica of the palace for a knock-down £320m (Stonehenge would be £815m, but it's hard to see how you could make a collection of stones any greener). Among other improvements, the report suggested replacing the palace's 760 sash windows with double-glazed replicas, and installing photovoltaic panels, ground-source heat pumps and masses of insulation. With such changes, the royal carbon footprint would be 400 tonnes of CO² lighter every year, it estimates, and the palace's £2.2m utilities bill would be slashed by 90%.

According to a bemused Palace spokesperson, there are currently no plans to raze the Queen's London home –it is a Grade I listed building (is the Queen allowed to destroy those?). The spokesperson also pointed out that the Royal family's green credentials were actually pretty decent already, thank you. In a recent (proper) energy audit, Buckingham Palace was rated a "C" (A being the highest and G the lowest) – very good for a hulking 18th-century pile. It's had a CHP (combined heat and power) unit since 1995, it uses water from a bore hole in the garden to cool the wine cellars and for some of the air conditioning, and some of the skylights are actually double-glazed. Although, that's nothing compared to Balmoral, which is powered by its own hydroelectric plant.

But more interesting than assessing the greenness of the Queen is the prospect of a new Buckingham Palace. A replica would be 10 times more expensive than the original, says Atkins, since the craftsmen and artisans required for the job are now highly-paid specialists, rather than jobbing joiners and plasterers. And that's using a concrete and steel frame and off-the-shelf materials, rather than proper stone. But why build a replica? Despite the palace's history, it's not really much of a building, architecturally, is it? Originally the home of the Duke of Buckingham, it was bought by George III in 1761. Since then, a number of architects have tried to improve it, including John Nash, Edward Blore and finally, Aston Webb, who gave it the neoclassical makeover we all know. Nikolaus Pevsner accurately described it as "a large and rather stiff country house" – surely not the right image for a forward-looking monarchy. Why not do something a bit more urban and up-to-date instead?

The obvious problem with building any state-of-the-art eco-palace, though, is the heir apparent. Given Prince Charles's views on architecture, he probably would rather build an exact replica than anything else. On the other hand, we could give it to Richard Rogers as payback for the Chelsea Barracks scheme, which was so roundly scuppered by the Prince's intervention last year. Or put it out to competition. Just think what a decent architect could do with £320m and a prime 40-acre site. But who could or should design such a residence? To the wrecking ball, citizens!

With its rippling facade and vast green roof, Chicago's Aqua Tower is a revelation. It's also the tallest building in the world to be designed by a woman

Jeanne Gang spent her childhood holidays out on the road with her family, looking at the bold new bridges and roads springing up across America. Her father, a civil engineer, also took her to natural wonders like the Grand Canyon and the towering rock formations of the Great Lakes in Michigan.

Gang grew up to be an architect with her own practice, Studio Gang, and now elements of what she saw on those road trips have come together in her first skyscraper, the Aqua Tower, a $308m (£188m) addition to downtown Chicago's architectural splendours.

The Aqua Tower, rising up in a dance of ever-changing concrete forms, is very different from its neighbours. Seen from the sidewalk, it really does have the look of a multi-layered Lake Michigan rock formation, albeit one that towers above the city. This is a Chicago landmark that has broken out of the city-wide straitjacket of right angles and smooth surfaces – as if Gaudi had taken up skyscraper design, or a spinning ballerina had morphed into a building.

It all began three years ago at a dinner following a Frank Gehry lecture in Chicago. Gang found herself sitting with architect and developer James R Loewenberg, who asked her to take a preliminary design for his Aqua Tower and make it sing. She jumped at the chance. After all, at 819ft, the Aqua Tower would be the world's biggest skyscraper designed by a woman (or, to be more precise, the tallest building in the world designed by a female-run architectural practice).

Skyscrapers are traditionally seen as an expression of overbearing male libido, a sort of mine's-taller-than-yours competition. So, even today, it is a surprise to find a woman building so swaggeringly high. (Zaha Hadid currently has skyscraper projects in five cities, but none completed). Gang politely dismisses such hackneyed assumptions. She is, after all, part of a team. "Our working method is very collaborative. Having said that, at least half, maybe more, of the staff here are women. I just think it's natural. I've always wanted to build. I was encouraged to make and repair things by my parents. But OK, I can't hide the fact that it's great to have done a skyscraper, even if I never do one again."

Gang, who wanted to be an engineer before she decided on architecture, grew up in a small town near Chicago. She says she thinks of the city as a mountain range rising up from the flat Illinois plains that flank Lake Michigan. "When we got the commission, we were partly thinking of building a mountain. But, being steeped in engineering, I also saw the project as a work of urban infrastructure. The tower is a machine plugged into the city – working for people – as well as being a kind of peak, or rock formation."

Behind its weaving balconies, this 82-storey residential and hotel tower is a largely conventional building. Conventional in plan, that is, but unexpected in terms of form, and laced through with amenities and luxuries. Although it opens in the middle of the worst recession to hit the US since the 1930s, most of its 740 flats have been sold.

From its waltzing balconies, the tower offers fabulous views of the city and its other skyscrapers, of the recently completed Millennium Park, and, of course, of Lake Michigan. It also boasts a swimming pool, sky gardens, a library and a billiard room. Meanwhile, an eight-floor terrace projecting over the entrance offers a running track and open-air hot tubs. The tower's garden roof is Chicago's most extensive.

Yet, despite this rippling tower's presence and sparkle, and the fact that it will bring Studio Gang international attention, it is not really the building this young Chicago practice wishes to be judged by. In fact, nearly every other project in its 35-strong office is low-key by comparison. Most are for public clients, none of them underpinned by skyscraper budgets. "I like different types of work," says Gang. "I don't want to be pigeonholed."

After training at the University of Illinois, then in Zurich, then at Harvard, Gang worked for Rem Koolhaas – an architect for whom the extraordinary is commonplace – on several key commissions, including the exquisite Maison à Bordeaux, a three-storey house for a wheelchair-user, crowning a hill that overlooks Bordeaux.

Gang set up on her own in Chicago in 1997, when she was in her early 30s. The fledgling studio's first project was putting a roof over the 1,100-seat bowl-shaped theatre of Rock Valley College in Rockford, Illinois. Inspired by nature and her knowledge of engineering, Gang came up with a six-piece steel roof that opens, in 40-ft triangular sections, like a giant flower in fine weather.

A tower that's bird-friendly

In Chicago's impoverished south side, her practice has built a much-admired community centre for foster children, and is working on an environmental centre, which rises in a happy weave of recycled materials from a site – part industrial wasteland, part natural wilderness – close to a Ford assembly plant. Gang likes working within an astute economy of means and materials. "Because of the nature of the sites and limited budgets, we're making the building out of what's available locally," she says. "We're like birds making nests."

As it happens, Gang is immensely fond of birds. In the design of the Aqua Tower, she has paid careful attention to the way birds see – or don't see – sheer glass walls, helping them to avoid fatal collisions. (A building with a complex facade is much safer for them, as are irregular window bars; birds pick up on the irregularity.) In her office, Gang has a number of bird's nests lined up on a window sill; she says she admires their spare, essential beauty.

Studio Gang is on to something here: a creative fusion of nature, found materials, inventive engineering, structural economy, and a matter-of-fact environmental awareness. And, of course, style. Even if the Aqua Tower, the glamorous, dancing skyscraper that will make Jeanne Gang an international name, is not typical of her studio's work, it is a mighty bird's nest of sorts, an urban rock face for people with a fondness for heights to nest in. Infused with a big mid-western spirit, Gang's architecture promises to soar in the coming years, whether built close to the ground and down to a budget, or 82 storeys up into the skies above Chicago.

Ecohomes need not look like the fallout from a science-fiction writer's nightmare. Some architects are sticking to traditional values

Think of environmentally friendly houses and what do you imagine? Probably a futuristic-looking house bristling with wind turbines. But these days it can be something more low-key as well.

From the outside, Raven Housing Trust's flats look like new versions of Victorian houses. The only hint that they are something special comes in the photovoltaic panels on the roof and the larger windows to maximise natural light.

These homes in South Nutfield, Surrey, are the first social housing properties to meet level five of the six-step code for sustainable homes, which the government uses to rate the credentials of green housing. Green features include a wood-chip-powered biomass boiler, a ventilation and heat-exchange system, low-flow taps and rainwater harvesting.

"People think environmentally friendly design will be wacky, with wind turbines on the roof and so on, but we wanted to make these homes look like any other," says Raven development manager Pete Trowbridge.

Meanwhile, Gentoo Homes housing association has taken a German design standard and tweaked it to meet north-east England tastes. Passiv Haus homes are so well insulated that they would not normally have chimneys, but Gentoo is putting on fake ones to help the homes blend in with their surroundings in Tyne and Wear. The bathrooms will have radiators; though not, strictly speaking, necessary, they at least provide somewhere for residents to hang their towels, says Allan Thompson, operations director at Gentoo Homes. "You have to make small concessions so it is not too radical a move for the great British public," he explains.

Out with the old?

But some architects think a new, greener mindset should be accompanied by a new aesthetic. Bill Dunster, who designs housing schemes without fossil fuels like BedZed and RuralZed, says green designs that ape old styles are a form of retro-escapism. "The language of the contemporary vernacular is different," he says. "We need to recognise that and embrace the reality of 21st-century life and the environmental challenges we are facing. Using traditional materials but a modern aesthetic is the way forward."

In Suffolk, Orwell Housing Association has doffed its hat to traditional building methods while using a rather unusual material - hemp. The highly breathable "Hemcrete" is sandwiched between panels, creating a structure that regulates temperature very well. Architect Cathy Hawley says the way the homes are clustered in small groups reflects the barns and 1950s council houses nearby, while the houses themselves are a pinky brown, a more low-key version of the pink renders used on the county's thatched homes. But the traditional theme stops there, as the buildings have greater amounts of glazing to the south to make use of natural heat and light from the sun. "They don't look like new-old houses," she says. "But I don't think we have made a complete break with the past."

In Milton Keynes, architects have designed homes that can be styled to suit any neighbourhood. The homes, designed by Rogers Stirk Harbour and Partners for a government competition to build a home for £60,000, are made of panels using old phone books as insulation with breathable glues. The Milton Keynes homes look fairly contemporary but a version of the design, built as a show house elsewhere by developer Wimpey, was given a brick and block skin for a traditional appearance. "We don't believe there should be a fixed aesthetic," says architect Ivan Harbour. "You should have a good system that allows buildings to be well built and insulated and perform well."

As the pressure mounts to make our new homes greener, it is not yet clear whether the modern will win out over the traditional. But if today's homes are anything to go by, the green homes of the future may well come in all shapes and styles.

Weblinks

Bill Dunster: zedfactory.com
Rogers Stirk Harbour and Partners: richardrogers.co.uk
Raven Housing Trust: ravenht.org.uk
Orwell Housing Association: orwell-housing.co.uk
Gentoo Group: gentoogroup.com
Ritches Hawley Mikhail: rhmarchitects.com