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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

Commission for Sustainable London 2012 calls for transfer of low-carbon lessons from Olympics to the wider UK industry

Organisers of the London 2012 Olympics risk missing a golden opportunity to inspire a step change towards a low-carbon economy, the green watchdog for the games has warned.

The Commission for a Sustainable London 2012 released its annual review on how the games' sustainable vision is taking shape. The UK's green promises were key reasons why Seb Coe and his team won the bid in Singapore in 2005.

Although the report said that the Olympic Delivery Authority, which has responsibility for construction and design of the venues and infrastructure, had maintained a high standard of sustainable design, the benefits to the UK's wider green economy could be lost before the games even begin unless "the knowledge in people's heads is captured before they leave".

With just over two years to go until the games begin, planning has now reached a critical stage as the ODA scales back in anticipation of the completion of venues next year.

The Local Organising Committee of the Olympic Games, responsible for running the event, will take on an increasingly greater role in delivering the sustainable targets for London 2012.

The report, Raising the Bar, says: "Our main area of concern lies in the wider commitments that were made during the bid or just afterwards. Broad promises have been made in official documents: 'to make the Olympic Park a blueprint for sustainable living' and 'to be a catalyst for new waste management infrastructure in east London'.

"With the exception of a few worthy initiatives, there is no comprehensive plan to make this happen. Furthermore, it is not clear what definitions lie behind these expressions or who is responsible for making them happen.

"With just over two years to go before the 'inspirational power of the Games' moves to Rio, never to return to London, these issues need to be resolved."

Shaun McCarthy, head of the commission, said: "Having an Olympics is an inherently unsustainable thing to do. To build all this stuff to watch some people run around – what's sustainable about that?

"We have to ask ourselves is it good enough just to have some great sustainable venues and put on a sustainable games which we are increasingly confident about, or will the Olympics really make a difference?

"Is this going to be something in isolation so we have one great big sustainable Olympics and then go back to business as usual?

"Or will the games actually change things? Because that was the promise that was made when we won the bid.

"A lot of carbon has been saved by comparison with business as usual construction techniques. If we can transfer that knowledge to the wider industry, we can save a lot more carbon than will be emitted in the whole of the Olympic Games.

"How can we use the magic of the Olympic Games to make that happen?"

McCarthy cited lower-carbon cement, low-toxin plastics and a zero landfill waste target as some of the achievements so far.

The stadium is the lightest Olympic stadium, using a quarter of the concrete used for the Beijing games, and features a lighting system suspended from a compression wheel made from re-purposed gas pipes left over from a different construction project.

McCarthy singled out the velodrome as an especially good example of sustainable design, with its ultra-lightweight roof and natural lighting and ventilation.

But he admitted that results have been mixed on the Olympic park. Zaha Hadid's feted aquatic centre, with a roof made from 3,000 tonnes of steel, was a "sharp lesson" in sustainable construction.

"That is a lot of steel just to cover a swimming pool and it is not necessary to have that much," McCarthy said, adding that the architect had simply been asked to design "a beautiful building" before the bid gained momentum.

But he said he was "very disappointed" that the energy centre in the Olympic park would run on gas, not biogas from onsite waste.

He also said he had concerns about London mayor Boris Johnson's approval of the ArcelorMittal Orbit tower in the park.

"It's very early days for the Orbit tower. Yes, I am concerned that it is a lot of steel. We are asking the Greater London Authority questions about it but we haven't yet had a satisfactory response.

"We would expect the mayor's office and the GLA to work to at least the same high standards of sustainability as the ODA."

An ODA spokesperson said: "We welcome the scrutiny of the commission and will continue to work with them to address any concerns they may have.

"The report states that the commission is pleased with our progress and they believe we are on track to meet challenging and extensive sustainability targets that have never been achieved before on a project of this size and scale.

"Our sustainability strategy was embedded into our processes at the start of the project and is already being delivered onsite.

"We are currently pulling together the best practice and lessons that have been learnt from the project so that they can be used by the industry for future projects."

Is a tower sponsored by a steel empire with emissions matching that of the Czech Republic appropriate as a lasting monument to the 'world's first sustainable Olympics'?

I'm a fan of oversized structures open to the public with fantastic views across cities, from the Eiffel Tower to the Rockfeller Centre. I'm even a fan of Anish Kapoor's work. (Isn't it time the Queen created a new post of artist laureate specially for Kapoor?)

But the decision to embrace ArcelorMittal, the world's largest steelmaker, as the sponsor for the £19m Kapoor-designed Orbit tower – or Boris's Olympic folly as it is becoming known – is one that really sends me into a spin.

I don't care that the tower resembles a 115m helterskelter tangled in Wembley stadium's arch. But during London's bid for the Olympics, sustainability was the buzzword. The London games would "set an example for how sustainable events and urban planning take place around the world in future."

Is the Orbit the type of landmark the organisers of the 2012 Olympics – who have some impressive green achievements under their belt – really had in mind when it said London would host the world's "first sustainable Olympic and Paralympic Games"?

The commission was agreed by the London mayor, Boris Johnson, and the Olympic minister, Tessa Jowell. But the choice of ArcelorMittal appears to have been thanks to a chance encounter between Johnson and the steel magnate Lakshmi Mittal "in a Davos cloakroom".

But for Johnson to make his mark on London 2012 and its legacy with thousands of tonnes of steel, one of the world's most carbon-intensive materials, appears at odds with the sustainable values of the Olympic Delivery Authority and the London Organising Committee of the Olympic Games and Paralympic Games (LOCOG) – and the spirit of the times.

ArcelorMittal's court challenge to Europe's cap-and-trade scheme, recently reported by PointCarbon, is its most recent act of resistance against the EU emissions trading scheme (ETS), the main mechanism for driving down CO2 levels in industry. ArcelorMittal's action brought before the European general court sought damages for being forced to pay for its greenhouse gas emissions because the company claimed the scheme threatened its business unfairly. The court dismissed the challenge last month.

Although ArcelorMittal is cagey about its own figures for allocation of carbon credits, climate campaigners have been hard at work poring over data for the EU ETS. Sandbag which campaigns to restrict the number of credits traded on the ETS, last year published a report with the help of Carbon Market Data claiming that by 2012 the company would have 80m carbon credits that it does not need, and was given for free. If sold, the company stands to make £1bn in windfall profits, says Sandbag. A tidy profit for doing, well not much, made by a company led by Mittal, who also happens to be Europe's richest man.

But this prospect hasn't prevented the company – along with the rest of the industry – from whingeing about its obligations under the EU ETS and demanding special treatment from the European commission by warning of "carbon leakage", that they claim would force factories to relocate to regions which have no cap-and-trade scheme.

In its corporate responsibility report, How will we achieve safe sustainable steel, ArcelorMittal admits its emissions are high. Every year it produces around 220m tonnes of carbon w – equivalent to the whole output of the Czech Republic or just under half of the UK's total emissions in 2009.

ArcelorMittal aims to reduce emissions from steel manufacture by 8% in 10 years' time and is already the world's largest recycler of scrap steel – to the tune of 25m tonnes a year – which it claims saves 35m tonnes of CO2 annually. ArcelorMittal has already won one of the first gold medals of the games with this PR coup to sponsor the Orbit. But it has missed an added opportunity to extra shine to its steel business with a commitment to using at least a large proportion of recycled steel in its construction.

But when I asked ArcelorMittal and the mayor's office to explain what makes the steel giant an appropriate sponsor of the lasting monument to the "world's first sustainable Olympic games", both refused to comment directly.

They referred me to a press release by the London mayor's office in which the only mention of sustainability comes in the notes at the bottom:

ArcelorMittal recognises that it has a significant responsibility to tackle the global climate change challenge; it takes a leading role in the industry's efforts to develop breakthrough steelmaking technologies and is actively researching and developing steel-based technologies and solutions that contribute to combat climate change.

Bryony Worthington from Sandbag says: "Boris really should have done his homework. While on the surface ArcelorMittal like to appear a responsible company they have been very active opponents of climate change regulations in Europe. They have also been amassing a small fortune in spare CO2 emissions permits as a result of lobbying for generous allocations. They now have more control over emissions trading in Europe than some countries."

As a Londoner and a sports fan, I wish he'd bumped into someone else in the cloakroom at Davos. But who, one of the other sponsors such as British Airways or BP? Last year ArcelorMittal had revenues of $65.1bn (£42.4bn). What other company would have £16m spare right now? In these straitened times, would London be better off without such a monolith to a steel empire with CO2 emissions equivalent to that of the Czech Republic?

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.

Campaigners denounce Grimshaw's green credentials as 'laughable' as practice set to be named third runway designer

From its opening in 2001, the Eden Project in Cornwall has come to exemplify the fightback against global warming – and its designer, Sir Nicholas Grimshaw, has basked in the green glow of a reputation as one of the country's most sustainable architects.

But environmental campaigners today branded the firm's green claims "laughable" after it emerged that the practice led by Grimshaw, the president of the Royal Academy, was set to be named lead designer of Heathrow's £8bn third runway expansion. The project will allow an extra 350 flights and transform Heathrow into the single biggest emitter of CO₂ in the UK, according to Greenpeace.

Grimshaw's selection has yet to be formally announced by Heathrow's operator, BAA, but rivals for the job have been privately informed by the client that the firm has won the contract, the architecture newspaper Building Design reported today. That was confirmed by competing architects, as environmentalists pledged to take direct action against Grimshaw in the coming weeks to try to persuade the firm to stand down from the job.

"Grimshaw trades on its reputation as a green architectural firm," said Leo Murray, spokesman for Plane Stupid, the anti-aviation protest group.

"They celebrate the Eden Project and are a founder member of the UK Green Building Council. They are a prime target for us because they are exactly the kind of firm that could back off because of the danger of reputational damage."

A spokeswoman for Grimshaw today declined to comment on the criticisms, stating: "We can't confirm or deny any involvement". BAA also declined to comment, stating that it would formally announce its selection in the near future.

The firm was defended by the UK Green Building Council, an alliance of architects and building services companies, which said Grimshaw "is in many ways at the cutting edge of sustainable design, as confirmed by its involvement in the Eden Project".

"The firm's involvement in a controversial aviation project has to be seen in the context of the UK's overall carbon budget," said John Alker, spokesman for the council. "If this is going to bust those budgets then we need to direct our anger at the policymakers involved. Where does this stop? Should we be protesting against the people that pour the concrete for coal-fired power stations?"

Today, campaigners against the third runway planted an orchard on land required by BAA for the expansion, which they have acquired in a bid to block the plan.

Actors Alison Steadman and Richard Briers were joined by the Liberal Democrat leader, Nick Clegg, and the poet laureate, Carol Ann Duffy, as well as local residents to plant trees on the land purchased by Greenpeace earlier this year.

"The government is absolutely wrong to stubbornly push ahead with a third runway at Heathrow," said Clegg. "How can Gordon Brown go to Copenhagen and credibly call for big reductions in carbon when he has such a dire environmental track record at home?"

The orchard includes a Cox's apple tree, sponsored by David Cameron, the leader of the Conservative party, which has pledged to scrap the third runway if it wins the next general election.

News of Grimshaw's selection comes amid a campaign by Plane Stupid aimed directly at architects who work on aviation projects.

The campaign group hijacked the Architect of the Year awards at the Intercontinental hotel at Park Lane last week when two activists dressed in evening wear took to the stage and tried to give a spoof award to Pascall and Watson, a firm of architects who work at Heathrow.

They tried to give the firm the "we don't give a shit" award "in recognition of their 50-year aviation portfolio, which includes expansion at Heathrow, Gatwick, Stansted, Birmingham, Manchester, Dublin and Abu Dhabi airports". There was applause from some architects in the room as the protesters were bundled out.