31 AUGUST 05

I began my eco-building diary on 1st September 2004; 365 days later my ambition to be in within a year has not been fulfilled. But for all the delays and frustrations, it's been a great year. And things can only get better...

SEPTEMBER 2004

I first encountered the tree that was to become our inspiration on September 20th 2002. Exactly two years later, site foreman Steve Archbutt arrived on our little patch of Clapham wilderness and began turning our dreams into reality. The design process had taken longer than anticipated, in part because we faced a highly constrained site but mainly because we had serious ambitions: our specification was for a house as beautiful and sustainable as the tree it would rise to embrace. Happily, our architect, Peter Smithdale of Constructive Individuals, met this challenge with enthusiasm and imagination.

OCTOBER

Cutting back, digging, levelling and shifting muck: it didn't take long to turn our verdant plot into a bleak expanse of mud. Although this laying waste was not a very ecological first step, the combined habitats of tree, pond, wildlife garden and house will give our 180 square metres even greater biodiversity than it started with.

NOVEMBER

Before we even had a slab to build the house on, we were installing some serious eco-kit in the mud: 200m of pipe down four 25m boreholes through which a refrigerant will eventually flow, extracting heat from the ground to warm the house in the coldest weeks of the year. Remarkably, the crew who drilled the holes were as consistently good-humoured as they were unremittingly filthy.

DECEMBER

The site demanded serious foundations: a concrete slab on nine metre piles. Although we didn't welcome the concrete truck to our eco-building site with open arms, we knew that this was the only way to ensure that the house would physically endure, perhaps the single most important criterion of sustainable design. Ford and I missed the fun of the main concrete pour which took place on December 24th. We returned from our holidays to find that Steve and his team had left us a big shiny Christmas present right in the middle of the site.

JANUARY 2005

The slab was not the end of the concrete story. A retaining wall had to be constructed to stop the neighbours sliding into us and our house-wide pond had to be stitched into the slab. Our pond is the most over-engineered frog-house in London - it took weeks to complete. It will be worth it though, helping us to keep cool and contented in the hot summer months to come.

FEBRUARY

In the snowy heart of winter, building did not feel like the best of career options. Nonetheless, site stalwarts Steve and George pressed on, digging our drains and connecting to the sewer. We decided that in our inner-city context the most ecological way to deal with this aspect of our waste production was to export it in the usual manner, albeit despatched with the most water-efficient toilets on the market and with a compost heap handy for occasional liquid relief.

MARCH

Our timber frame got lost in the post in March, so we occupied ourselves building garden walls and fences. The walls at the front of the house were built with reclaimed bricks and lime render, minimising the pollution and carbon emissions of manufacture and ensuring that the walls retain a flexibility that will help them to survive if the earth moves beneath them. At the back of the plot, local metal-designer Jonnie Rowlandson got wonderfully carried away making us a fiery organic fantasy of a fence out of scrap steel, copper and bronze.

APRIL

Six months in, we finally penetrated the third dimension. Our timber frame, made from light-weight, high performance 'I-beams', had to be cut to size on site, but after months of mud and concrete Steve and George were happy to be breathing sawdust at last.

MAY

Having got into top gear, we had to shift rapidly back to second when the crucial bit of steel designed to hold up the back of the house got made wrong (twice). The front of the house rose as far as it could, but it felt like we were paying a penalty for this thoroughly un-eco component in our otherwise supremely sustainable structure: the timber frame components all came with Forest Stewardship Council (FSC) certification. Eventually the steel arrived and the pace picked up once again, as did cheerfulness both on and off site.

JUNE

After years of planning, the emergence of rooms, or at least room-like spaces, was extraordinarily exciting. With no sheathing on the stud walls we could still see right through the building, but we got our first real sense of how far and wide we will be able to swing our four cats. In fact, we have kept interior walls to a minimum, creating large spaces that will be flexible enough to satisfy the needs of the inhabitants of the house over its long life without too much hacking about.

JULY

With the installation of our triple-glazed windows and external wall sheathing, it seemed feasible for the first time that this entertaining but challenging hobby might result in a space where Ford and I could actually live. Our exceptionally well-insulated building envelope will help to ensure that our experience here will not only be very comfortable but also carbon-free.

AUGUST

Our roof was delayed (surprise!) but when it did finally go up we were suitably gob-smacked. Our team of joiners - Steve, Mark, George and Pete - turned a pile of FSC Douglas Fir into beautiful branching trusses to hold up the roof and our solar power station. The roof was difficult to engineer because it is almost entirely pitched one way - south - but we will be rewarded in years to come with an abundance of hot water and cool electricity.

SEPTEMBER - NOVEMBER

There is still rather a lot to do, but once the house is weather-tight the pace should quicken. In theory. Watch this space from more eco-building tales in the months to come.