25 JANUARY 06

We have been doing rather a lot of painting this week, creating bright white walls with sweet-smelling natural emulsion, but I keep thinking of wallpaper: richly patterned William Morris wallpaper. This is not because I have a sudden urge to cover our walls with the stuff but because I feel, somewhat indulgently, that Morris would have approved of Tree House.

William Morris founded the Arts and Crafts movement, a late nineteenth century response to industrialisation and mass production that promoted traditional skills and craftsmanship. Where division of labour stripped craftsmen of their creative involvement in production, the Arts and Crafts pioneers sought not only to hold on to this involvement but to elevate the craftsman to the status of an artist.

Tree House is a highly crafted building, built by a skilled team of craftspeople whose commitment to quality has kept the project in the realm of dreams rather than nightmares. This week, the glittering stained glass panel created by artist Sarah McNicol was installed at the centre of our kitchen (www.juicyglass.com), framed by beautiful beech shelves made by cabinet-maker Stephen Edwards (www.ecointeriors-uk.com). Carpenters Steve Archbutt and Nikolin Deda began their final feat of bespoke on-site joinery: the curved staircase that winds round and up two Douglas fir tree trunks. Off site, contractor Martin Hughes and architect Peter Smithdale (www.constructiveindividuals.com) have redoubled their efforts to ensure that Tree House emerges as an integrated work of art, craft and engineering.

The exposed trusses in our top room have a medieval character that Morris would have loved and everywhere we have turned to simple, natural materials to bring character to the interior. Our use of stained glass in a domestic context was pioneered in the Red House, the ground-breaking home built for Morris in Bexleyheath by Philip Webb. We have even treated the garden as an extra room of the house in the tradition of Gertrude Jekyll.

But if Tree House boasts some of the qualities of the Arts and Crafts movement, does it also suffer from its weaknesses? Morris and his followers are often criticised as well-heeled idealists whose pursuit of craftsmanship never reached beyond the pockets of the rich. Is a highly crafted bespoke project such as Tree House just as elitist with little relevance to the challenges of mass house-building?

Only if you take a very narrow view of craftsmanship. As well as a beautiful kitchen and staircase, Tree House has super-insulated walls, high performance windows, an exceptionally air-tight outer envelope and three integrated renewable energy technologies. If any of these components had been built or installed carelessly, as they often are on British building sites, we would stand little chance of achieving our tough 'zero carbon' energy goal. If craftsmanship is seen as a commitment to quality in all aspects of construction, it should be a priority for any eco-build, regardless of budget, from day one.

Craftsmanship may not be a sufficient condition for eco-building (the Red House turns its windows to the chilly north) but it is a necessary condition. Unfortunately quality remains a huge challenge for an industry with a history of building houses with cheap heating systems that disguise all manner of failures in the building fabric. A move towards greater off-site prefabrication may help to address this problem in mass housing but nothing beats skilled and committed people on site.

Morris recommended having nothing in your home that you do not know to be useful or believe to be beautiful. He may have been a crusty old snob - and I'm not convinced that his own wall-paper consistently meets these criteria - but this is a worthy maxim for our careless, throw-away world.