Cheap Zero Heat House

In a Somerset village, a builder is creating zero-carbon homes for less than the cost of conventional ones.

By Ashley Seager The Observer Sunday August 16 2009

It's unlikely that you would turn up at a pretty, quiet Somerset village in search of any kind of revolution. In fact, you'd be hard pushed to spot anything revolutionary in the village of Chewton Mendip, save perhaps for a few solar panels on top of the local school.

Blink and you'd miss three terraced houses forming a corner of two streets in the village. They blend in perfectly with the other traditional stone houses. But behind the facades lie brand new homes built with ultra-modern materials and which already meet the government's strict zero-carbon rating that all new houses will have to meet from 2016.

And, crucially, they have been built to a comparable cost to conventional houses, blowing away in an instant the claims of the big housebuilders that meeting the 2016 target will entail huge cost and put up property prices. It's generally true that in any industry, innovation comes from the small start-ups rather than the big incumbents, and local builder Arthur Bland, combining for the first time some advanced new floor, wall and roof technologies already available in Britain, is proving the point.

"These are the most thermally efficient houses built in the UK in 2008 and are twice as good as the PassivHaus [energy efficiency standard] in Germany," says Bland. "And if I had built them on a larger scale on a larger plot, they would have been cheaper to build than conventional houses; I am quite sure of that."

They say the three most important things in building an eco-house are insulation, insulation, insulation. And maybe airtightness too. And that is what Bland's house embodies: it is so efficient at retaining heat that it does not need any form of heating. In an English house? Surely some mistake?

Bland explains that the revolutionary insulated floor system, from a company called Ecoslab, combined with a polystyrene-and-concrete wall system from Logix and a roof system from Unilin, give the house a "thermal envelope" from which heat and air cannot escape. Daily living generates enough heat - from TVs, kettles, the warm backs of fridges and the people who live in it - that no further source is needed.

Airtightness might sound suffocating, but in fact the houses have a circulation system that changes the air five times an hour. And the clever bit is an exchanger that captures the warmth from stale air, which is extracted from the house by vents, and reuses it to heat water and the air in the rooms. That system is made by a Swedish company called Genvex and costs about £6,000 to install - but once you deduct the cost of a traditional heating and hot water systems, Bland says you are left with a negligible extra cost per house of £500. For the homeowner, the advantage of Genvex systems is that they last much longer than traditional boilers, which need replacing at least every 10 years.

The windows are all triple-glazed and wood-framed to keep heat in. They can, of course, be opened if the house gets too hot in the summer but the Genvex will also provide cool air to keep the places at a constant temperature.

The windows and walls are also very good at keeping sound out - a significant advantage for future homes being built on brownfield sites near other houses and roads. The absence of radiators leaves walls freer than they would have been and the airtightness, if nothing else, means there are no nasty draughts in the winter.

Bland's former wife Linda lives in the middle house with her two children and loves it. She moved in last December when it was completed and so tested it through the cold snow of the spring, when temperatures dropped to -9C.

"For a few days I had a small electric heater on in the living room just to raise the temperature a bit. But after half an hour the house was too hot and I had to turn it off," she says.

"It is a great house to live in and I have no complaints at all. The air does feel dry, though, and I have to water the plants more than I would have done. But that is the only thing I would say. I don't have to lug solid fuel around any more like I used to in other houses I have lived in so I love it."

The house has low-energy lightbulbs, not only because they consume less electricity but also, explains Bland, because the heat from conventional ones would make the house too hot.

He points out that the best thing to do when you have had a bath is to leave the hot water in it to cool, since the heat will be sucked through the bathroom's vents and recycled by the Genvex system into more hot water. "You can get obsessed by this heat business - but it is important," he says.

The three houses share a rainwater harvesting system via a big tank in the communal garden to the rear. The rainwater is used for dishwashers, washing machines and toilets. About 75% of the houses' annual water consumption is provided in this way.

The houses are not yet zero-carbon in the true sense of the phrase since the planning laws in the village's conservation area prohibit the use of renewable energies such as solar panels or wind turbines. As a result, each uses about £600 a year of electricity from conventional sources.

But Bland stresses that the houses meet all the Code Level 6 requirements of the government's code for sustainable homes - a set of rules which is gradually tightening the regulations for new buildings to reduce their carbon output - in terms of the construction.

The addition of, say, solar photovoltaic panels would easily make them zero-carbon or even carbon-negative in the sense that they generate more clean energy than the consume, exporting the surplus to the grid.

The building cost for the three houses was £300,000 for a total dwelling space of 280 square metres. That sort of figure - about £1,100 a square metre - should make the big housebuilders sit up and take notice, especially as Bland says the awkward plot shape and stone frontage added about 20% to his costs. In other words, slightly more standard houses would be cheaper than conventional dwellings even if the solar panels were added on. His system is also quicker than conventional housebuilding.

"There is no great mystery to building houses. If I had not faced the constraints I did on this project, I could easily come in cheaper than conventional houses," he says. "I have simply put some new kinds of products and processes together for the first time. But they can be used flexibly to create any kind of building."

But the big boys, of course, don't like change. Bland took his system to the Ministry of Defence, who had a long-running contract with a volume housebuilder for homes for service personnel. The big housebuilder is charging the MoD £2,000 per square metre for the homes - a high price - and was, not surprisingly, impervious to the MoD's request to copy Bland's model, which would have saved the public purse money both in construction and running costs.

Although producing concrete needs a lot of energy, the Bland houses use much less than traditional houses and require many fewer truck journeys, saving on emissions as well as noise and disturbance - because they use the excavated earth from the foundations as a base for the Ecoslab floor system instead of carting it away to landfill.

You no longer have to imagine the future of housebuilding. It is already here.

Reply to
Doctor Drivel
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It said comparable, not less than, and probably meant not much more than.

And an electricity bill of £600 per year is huge for what the place purports to be.

Snip

Reply to
Roger Chapman

If that answers all the hot water needs and cooking, that's ok I think.

From what I've read of passivhaus designs, electricity usage is very subjective.

Some users really get into the mindset of low energy usage and reap the rewards - others feel that they no longer have to be careful.

Overall though, my impression of the build was excellent insulation and airtightness with a fairly conventional build approach (perhaps rather more cast concrete than is usual for domestic builds) - plus they fitted a heat recovery ventilation combined with an air-source heatpump.

Getting the build quality on the airtightness is probably one of the big things to actually get to work in practice.

Reply to
dom

Overall though, my impression of the build was excellent insulation and airtightness with a fairly conventional build approach (perhaps rather more cast concrete than is usual for domestic builds) - plus they fitted a heat recovery ventilation combined with an air-source heatpump.

Getting the build quality on the airtightness is probably one of the big things to actually get to work in practice.

Reply to
Doctor Drivel

Sounds somewhat better than this one:

California's 'Zero Energy House' is actually massive fossil hog

Reply to
Rod

See also

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for a large detached house built for himself by a (semi-?) retired local builder to better-than-passivhaus standards for a cost ex-land but including his own labour at realistic costs of, I think he said, around £250K.

Reply to
John Stumbles

Producing concrete generates a huge amount ot CO2. Not that CO2 is anything to worry about since "man-made global warming" is the biggest scientific scam since Piltdown Man. So go ahead with building efficient houses if but only if that saves you money.

Reply to
Matty F

No, other way round, £195K. He excluded his own labour and the following quote seems to me to suggest that all he writes on costs should be taken with a large pinch of salt. And all the other savings he claims to have made by doing the work himself seem to be largely double accounting.

"My own labour for 163 days cost me nothing other than a few grey hairs. It could be added in at £40, £50 or £60k depending how you feel about my worth."

FWIW there was a new build 4 bed house near me on what claims to be an exclusive enclave sold for £250K in 2007. Applying the Dribble formula this couldn't possibly have cost more than £80K to build and if we take off builder's labour at the inflated figure above we get back to £20K for the materials.

Reply to
Roger Chapman

Another natural supporter of UKIP and its pseudo science.

Reply to
Roger Chapman

It isn't, but it looks like mankind will bankrupt itself before it cooks and drowns itself, so it may not be so relevant after all..

All these problems are soluble by a simple 70%-90% reduction in population levels, and we can confidently look forward to that within the next 60 years.

The government should restrict its activity to solely taxing carbon fuels, if that is what it cares about.

Reply to
The Natural Philosopher

You made that up.

Reply to
Doctor Drivel

What bollocks!!!

Read economist Fred Harrison and his book "The Silver Bullet". The earth's land can sustain the lot of us. It needs unlocking. It is in the hands of rent taking, land speculating sharks.

Reply to
Doctor Drivel

The average 4 bed house costs round £100,000 to £120,000 to build. Insurance companies can tell you the rebuild costs of house. Know that off and the land value emerges. The bricks on the land are work little.

Reply to
Doctor Drivel

From another natural supporter of the Green movement and its pseudo science.

Reply to
The Medway Handyman

There are similarities in both scams. It's difficult to oppose so- called qualified scientists with PhDs. However, truth will out. And the scientists who went along with the scams will be ridiculed for ever. I shall be making a list.

"Piltdown was proclaimed genuine by several of the most brilliant British scientists of the day: Arthur Smith Woodward, Arthur Keith and Grafton Elliot Smith. How did these faked fragments of bone fool the best scientific minds of the time? Perhaps the desire to be part of a great discovery blinded those charged with authenticating it. Many English scientists felt left out by discoveries on the continent. Neanderthal had been found in Germany in 1856, and Cro-Magnon in France in 1868. Perhaps national pride had kept the researchers from noticing the scratch marks made by the filing of the jaw and teeth. Items that were apparent later on to investigators after Oakley exposed the hoax.

Even as early as 1914, though, there were those that doubted the fossils. William King Gregory wrote, "It has been suspected by some that geologically [the specimens] are not old at all; that they may even represent a deliberate hoax..." "

Reply to
Matty F

yeah..It occurs to me that parties like the Greens, BNP, UKIP etc etc. all exist because of a problem that is real, and is not being addressed correctly by the mainstream parties.

There is a climate change problem. The greens say they have the solution: They have not. There is a population problem: The BNP claim they have the solution, They have not. There is a problem with Eurocentralisation and over bureaucracy: UKIP say they have a solution: They have not.

In fact, when you look at all they parties, you will see tyhey all gain support by claiming to address a particular problem Which they diont actually have a solution for. Labour claims it has the solution to a fairer society: It does not. LibDems claim they have the solution to almost everything, but don't have the solution to anything. Tories claim they have the solution to the problem of too much, expensive government. Hmm. Turkeys don't vote for Christmas..

Reply to
The Natural Philosopher

I am no supporter of the Green Movement.

The case for GW is cogently argued and hangs together with only the minor detail in any degree uncertain.

The deniers on the other hand use lies as their stock in trade and and very often what one denier claims conflicts with what another avers is the absolute truth.

The deniers tactics can be seen clearly in what they say and how they chose to attack those who accept that GW is occuring. Two recent instances spring to mind.

From the stolen e-mails they widely quoted the one about the trick of adding back the real temperatures making out that this proved that the recent temperature record had been falsified when they must have known that the actual problem was getting temperature data derived from tree rings to match the real record in a environment of rising CO2.

Then there was the melting glacier fiasco where a mistake by social scientists (surely an oxymoron)at the IPC who seem to have believed what they read in a newspaper led to doubts being cast over any notion of glacial melting and a totally fictitious counter that even took in the likes of David Bellamy. What may well have started as a typo (2035 for

2350) became the latest stick to beat the scientists with.
Reply to
Roger Chapman

The two situations have no parallel.

In an era of much lower levels of education, much poorer communication, and when a very small elite group called themselves "scientists" - everything functioned as an old boys club.

Today - there's lots of reasons why we might be lied to - politicians saving their own skins, corporations after profit, scams and hoaxes -

*BUT A WORLDWIDE CONSPIRACY OF SCIENTISTS IS NOT ONE OF THEM*.

We live in an era where major scientific views are endlessly scrutinised and tested, wholly independently in universities and research centres throughout the world.

Climate change data has been contributed by weather services throughout the world - then evaluated independently in others, and findings published in peer reviewed journals - ready for yet more scientists to pore over the detail and attempt to find fault.

That's how international scientific research works.

I've got a PhD. I did my research work in a top British university, as well as many years both as an academic and in a government research centre - and I can say with *ABSOLUTE CERTAINTY* that the research process would sniff out any deliberate falsehood of the magnitude of climate change.

Frauds can only be gotten away with when they involve small groups of people - one scientist, one research group - maybe by inappropriate influence you could drag in a few more - *but not a conspiracy spanning thousands of experts throughout the world*.

Or you might get away with false claims for little things of no great scientific importance - the stuff that may not be checked that often.

False archaeological claims - based on a single find that few have access to? Maybe - for a while.

The whole of climate change being based on false claims? You might as well believe the moon landings were faked, that the earth is flat - and that you don't need urgent help from the psychiatric profession.

One simple way of knowing that's true - is that the person that discovers a scientific fraud (or simply a mistaken understanding) of that magnitude - is going to hugely enhance their reputation - by heralding in the *new* understanding.

Now - about climate change - I know my stuff in my own field, I have years of experience of international research - BUT I AM NOT QUALIFIED TO EVALUATE GLOBAL WARMING.

To all of you that think you can tell, by looking at the weather out of your lounge window or listening to the weather forecast - *you can't*.

Like me, you lack the skills to determine what's what with global warming.

That's how it is - for some things you have to rely on experts - your own "common sense" *cannot* tell you the answer.

I KNOW FOR CERTAIN THERE IS NO CONSPIRACY THROUGHOUT THE INTERNATIONAL RESEARCH COMMUNITY.

I KNOW I'M NOT ABLE TO EVALUATE CLIMATE CHANGE FOR MYSELF AND HAVE TO ACCEPT EXPERT OPINION.

Reply to
dom

No wonder he votes Tory - he wants the end of the world.

Reply to
Doctor Drivel

We know about Pitdown man. Global warming and climate influence by man is real. Crap pours out 24/7/365. This crap ruins people's lungs.

Reply to
Doctor Drivel

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