It’s a dull, grey, autumn day. But inside Weobley primary school the classrooms are so bright, airy and colourful that you hardly notice the wind and rain outside.This winter, pupils’ toes will be especially warm. The school’s underfloor heating is fed by a massive state-of-the-art furnace, which burns locally grown wood chips, and there are no draughty corridors - all the walls are insulated with recycled newspaper pulp.

Weobley primary, near Leominster in Herefordshire, was officially opened by Agriculture Minister Jeff Rooker last October. It has been hailed as the United Kingdom’s most eco-friendly school. From the outside the red-brick and timber building with its terracotta-tiled roof could be just another modern school. But appearances can be deceptive, for the school’s design has incorporated every environmentally friendly trick in the book.

Headteacher Geoff Williams, who, with his staff and 181 pupils, has been in situ since last April, is happy with his new school. “It’s so well thought out,” he says. “The architects listened to the teachers. They didn’t just design a school to win awards.”

The idea for the school came out of the 1992 Earth Summit in Rio, Brazil. The area’s education authority at the time, Hereford and Worcester County Council, wanted to make its own contribution to local sustainable development, and the picturesque villageof Weobley needed a new primary school. So, with the help of grants from the Ministry of Agriculture, Fisheries and Food, the Rural Development Commission and the European Union, the eco-friendly school project was born.

There have been other eco-friendly schools, but Weobley is the first in the UK to have a sustainable heating system using locally harvested wood for fuel. At one end of the building is a giant fuel store, which receives a delivery of wood chips twice a week. Hydraulic rams move the fuel forward, and it is automatically carried up into the furnace. Hot water is pumped from the boiler to the underfloor heating system. This also heats Weobley high school next door. There’s little waste - what there is goes into an ash bin to be sprinkled on to the gardens. And the only smell from the boiler is the pleasant waft of wood smoke.

Although the wood fuel system was more expensive to install than conventional systems, it should prove cheaper in the long term. And the use of sustainable wood fuel heating is intended to promote rural industry - the fuel comes from the 7Y Machinery Ring, a co-operative of local farmers that grows poplar and willow.

Geoff Williams admits that when the boiler was first tested last April, it worked almost too well. “It wasn’t a cold day - the high school had its windows open to try to get the temperature to drop. We are still trying to get the balance right between ventilation and heating. If everything is shut up, it does get very warm.”

Classrooms are arranged in a line the length of the building, which faces south across open countryside. There’s a practical area shared by each pair of classrooms, a centrally placed library and a combined gym and canteen just off it. Staff can control a natural flow of air through the classrooms using electrically controlled windows high on the building’s north side and low windows on the south.

The building also makes maximum use of natural daylight, avoiding, as much as possible, the need to use the lights. They, in turn, are controlled by sensors which adjust light levels depending on how bright the sun is. They go off automatically when the last person leaves the room.

Even the materials used to construct the building were subject to close scrutiny - locally made bricks, timbers and clay tiles were matched with floor coverings made from natural materials, and the paint on the softwood windows is water soluble.

Outside, the grounds are to include a conservation area. A pergola on the south side of the building is to becovered with climbing plants. This and a line of deciduous trees will filter out low-level winter sunlight to the classrooms.

But what is Weobley primary like to teach in? “Absolutely wonderful,” enthuses deputy head Ann Davies. “We are very privileged. I keep telling the pupils they’re probably the luckiest children in Herefordshire. If you open the low windows, you get this up-lift - this lovely through draught. It’s very cleverly designed.”

And as for educational implications, they are “potentially enormous”, says Geoff Williams. “High school students, for example, could monitor the moisture content of the wood fuel in science. And in terms of environmental messages, we’re constantly hearing about global warming and the ozone layer. I’ll be able to emphasise to the children that we’re not using a finite energy resource.”

The building won the 1997 Built Environment Innovation category of the Environmental Award for Engineers. But its architect, Dermot Galvin, describes it as more than just a showcase. “It’s not just ‘this is what we can achieve’. It’s ‘this is what we can achieve within a modest budget’. We had special funding for the wood fuel part of the building, but the rest was just within the county council’s standard school budget.

“This school shows that it’s possible to create a building which has a better environment for its occupants. But it’s not just about using less energy. It’s about what the building might contribute to the occupants, how it might be of use to the local community and how it might be a teaching aid, not just for the children but generally for the local community. A school is an ideal vehicle for spreading this philosophy.”