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Somewhere on the road to Nottingham 鈥� and the university鈥檚 energy efficient C60 house 鈥� the scales fell from Alan Heywood鈥檚 eyes, leading the Stoneguard project manager to say: 鈥淚鈥檇 find it hard to revert back to using traditional methods and products considering what I鈥檝e learned so far on this project. It鈥檚 a conscience thing.鈥�

In reducing the carbon dioxide emissions of a typical family home by 60% (to meet the 2050 target set out in the 2003 Energy White Paper), Heywood and the team behind the C60 house want the entire industry to share his 鈥渃onscience thing鈥�. Once it is up and running, the performance of the house 鈥� designed by staff and students at the School of the Built Environment in a jointly-funded project with construction technologist Stoneguard 鈥� will be monitored over many years and, hopefully, the findings will influence future housebuilding.

Getting the spec right for external windows and doors is crucial, especially as the design has 50% of the wall surface glazed. In fact, external insulation (walls are 150mm EPS with a Sto render finish) and windows are the most important factor to get right in the drive to improve domestic energy efficiency. And while

it is easy to see the environmental benefits of a rainwater harvester or an earth-air heat exchanger system, the green benefits of other innovations are less obvious.

鈥淭ake these internal doorsets for example,鈥� says Heywood. 鈥淲ith this set from NBS, it should take about 22 minutes to fit a door. That鈥檚 seriously quick.鈥�

Pre-finished doors

Heywood says that on any project, door-hanging is a pain. 鈥淲ith house building, when you鈥檙e trying to get through as many as possible as quickly as possible when to hang the doors is always a tricky decision.鈥� The advantage of the NBS doors, explains Heywood, is that there is no need for joinery on site. 鈥淚 glue on my architrave and the doors come with all furniture attached. I don鈥檛 need a carpenter to start fitting locks or setting hinges with chisels and routers. It鈥檚 all pre-finished, meaning no joinery on site. It鈥檚 a massive saving on time, resources and labour.鈥� Fewer people travelling to and from site and fewer power tools being used adds up to fewer carbon emissions.

Stoneguard鈥檚 search for the right glazing led it to Internorm, an Austrian company that claims to be the biggest window manufacturer in Europe, was brought into the fold. Expert at working with 鈥減assive houses鈥� across the continent (a passive house goes even further than the C60 house by reducing carbon emissions by up to 90%) the firm was recommended to the Nottingham team by a passive housebuilder in Wales which had used Internorm鈥檚 Edition Passiv, a high-spec triple-glazed system.

UK representative, Thomas Fr枚hlich, was initially a little surprised at the project. 鈥淚n Germany passive houses have existed for 25 years so when we got involved, I said, 鈥業t鈥檚 not really a house for 2050, because we can, and are, producing this kind of house now, in fact to even higher standards.鈥� Nevertheless, Fr枚hlich accepts that the C60 project is as much about intent and good practice as it is about pushing the envelope. 鈥淚n Britain the awareness of why it鈥檚 worth paying more for energy efficient products is not there. This project is at the forefront of changing perceptions.鈥�

That change, thinks Fr枚hlich, will come from the consumer. 鈥淚t will start with the private customer. Big housebuilders are not interested as long as they don鈥檛 have to be, they鈥檙e profit orientated. They鈥檒l take the cheapest product and build it for the lowest cost. That鈥檚 how developers think. I should know, I used to be one in Germany.鈥�

Heywood agrees and points out that energy performance statistics relating to domestic windows are starting to appear and reckons it won鈥檛 be long before people purchase houses on the basis of such statistics.

Thomas Fr枚hlich, Internorm

big housebuilders will take the cheapest product and build it for the lowest cost 鈥� that鈥檚 how they think

Commercial venture

For the C60 house, Fr枚hlich recommended Edition 4, Internorm鈥檚 triple-glazed wood and aluminium system. It knocks U-values down to around 0.7 W/M2K 鈥� half of what the Regs stipulate. It includes blinds between the first and second pane 鈥渟o you don't need curtains鈥�, suggests Fr枚hlich.

They were not supplied gratis, however, like many of the other products and services on the project. Fr枚hlich, smiling broadly, comments: 鈥淲e said to Stoneguard you can鈥檛 get a Merc for free. But we鈥檒l supply the products for manufacturing costs. The materials are really expensive and in Britain there is nothing comparable.鈥�

A straight talker just like Fr枚hlich, Heywood states plainly: 鈥淚f we could have found the same quality here we wouldn鈥檛 have gone to Austria for it. And anyway, it may sound mercenary but at the and of the day it鈥檚 a commercial venture for all those involved.鈥�

Installing Internorm鈥檚 triple-glazed units requires specialist teams be brought in.

Air-tightness is essential, foil sheeting must be fitted, and the units themselves must be carefully handled (they are considerably heavier than other window types).

At the moment, only two teams in the UK are accredited to do such work, one in Scotland, the other in London. So at Nottingham, it鈥檚 likely an Austrian team will be used.

Internorm has also provided all of the elements for the sunroom, a double height space that will help control internal room temperatures. 鈥淲e鈥檝e designed the whole space. If the sun is too strong, the roller shutter goes down automatically,鈥� explains Fr枚hlich.

Heywood has until the end of March next year to deliver the project. The steel frame has been built, and he has already built up to DPC level on site. Not bad considering he started the project just four months back.

And while his conversion to green building may be a 鈥渃onscience thing鈥� there are other factors that swung Heywood鈥檚 thinking towards new processes. From a site management point of view, he says, the green approach makes building easier, as many of the products and systems are manufactured offsite. Ultimately the customer will benefit too. 鈥淯ntil energy efficient housing is available on the mass market, the customer gets a raw deal on the biggest purchase they鈥檒l ever make,鈥� says Heywood.

However, if housebuilders are willing to learn from the C60 house, both industry and consumer, along with the environment, will be the major beneficiaries.