Visual arts: Rubbish. Absolute rubbish

Wall-to-wall junk. Well, that's what it looks like. Rusty, broken, yellowed objects strewn in all directions, and in the corner three figures huddled in intense conversation - discussing their plan to bring order to the chaos.

The sculptor Tomoko Takahashi and her helpers have spent weeks gathering this mass of material for the forthcoming Saatchi exhibition, Neurotic Realism, and it is going to take a further two weeks to transform the odds and ends into an ambitious, knock-out art installation.

Standing at just over 5ft, Japanese-born Takahashi is dressed for comfort and work. She wears a large red shirt, baggy shorts over thick tights and black, rectangular-framed specs, and has her hair casually tied back. I describe her because you're unlikely to catch a glimpse of her. To say that Takahashi is extremely media shy is an understatement. The artist has consistently refused to have her photograph taken - she wants her art to speak for itself - and in the artists' biographies put together by the gallery she has chosen to be represented by a clock face rather than the usual photographic portrait.

Takahashi breaks away from the group and picks her way across the gallery toward me. "I'm treating this space as a blank, white canvas," she says, before disappearing to unearth a packet of cigarettes and lighter, no easy task in a warehouse gallery that conjures up an image of your local scrap merchant and refuse dump all rolled into one.

Cigarette in hand, she is warm and friendly, her broken English falling out in a rush as she tries to explain the mechanics and thought processes behind the task before her. Somehow, she will bring a satisfying order to the jumble surrounding us. She will tidy up the mayhem, and make sense of it all.

I, too, would like to bring some order to the mind-scrambling clutter of old cookers, radiators and filing cabinets, but my only answer would be to hire half a dozen skips and fill them. Takahashi's approach is a touch more purposeful.

However, it's early days, and Takahashi admits that she still only has a hazy idea of what the end result is going to be. There will be bundles of cables hanging down from the beams and narrow paths weaving through debris attached to the floor, and it will be dimly lit, but any more than that she can't say. "I don't have an aim. It's more like an improvisation. With this type of work, I just gather the things that I like and then I play around with it."

Takahashi, who, conveniently, lives above a junk shop in north London, has always worked with electrical gadgets and office paraphernalia, imposing artistic control on an indecipherable mess. One of the hardest things, she says, is simply remembering all the things that are at her disposal.

The motley collection of dilapidated computers, domestic appliances and well-used gadgetry is, I was surprised to learn, not just a mass of discarded rubbish. A lot of the things are on loan and have homes to go to, once the exhibition comes to an end. Takahashi likes the idea that the objects have owners and are of value to someone. And by taking them away from their owners, she sees herself as giving them a new lease of life, particularly the electrical equipment, much of which has not been plugged in for years.

As far as Takahashi is concerned, it's all valuable "historical evidence" which, she says, is "a bit like archaeology", a "lost civilisation" that has, until now, been stashed away in various sheds and cupboards.

Some items were scavenged from skips - a leftover from art school days, when money was short and the use of bricolage a financial necessity - while other pieces were snapped up at car boot sales. And the winner of the 1997 East International award has also recycled two of her earlier installations, Beaconsfield and Clockwork, both of which are now owned by the Saatchi Gallery. A close inspection reveals that some of the hammers, nails, and even old shop receipts, carry silver tags marking them as Saatchi property.

Just visible under the carpet of tangled wires, old TV sets, electrical gadgets and rusty bits and pieces, lines of black and silver sticky tape sweep out in all directions marking out a basic floor plan. These took five days to map out, but without them, Takahashi says, she could never have got to grips with the huge gallery space: "They gave me a sense of the space, so as I did it, I got to know how big it was. Now I am very familiar with it and not too scared. It's just guidelines and has made it manageable. The composition itself will go on top, so will ignore these lines."

Tucked to one side, a scrunched-up sleeping bag, surrounded by cartoons of fruit juice and mince pies, marks out Takahashi's sleeping quarters; the artist's total self-immersion in her works means that she often sleeps on site, working through the night and sleeping in the morning. "The night is the best," she says. "The most manic time is after midnight until seven o'clock in the morning." Other tell-tale signs of life dotted around the vast, echoing, 30-by-18-metre gallery include overflowing ashtrays, a half-eaten loaf of bread, and a miniature pool table.

Takahashi is not one to analyse her own work: "I do not think it's relevant," she explains. "It would be like analysing your birthmark, which I'm not that keen to do." She cannot say who she is influenced by or what her goals are. Instead she works instinctively, only coming to understand her works sometimes months after they are first put together.

"It's all subconscious. I really don't know what I'm doing. I know the direction, like a painter. It's a traditional way of working and takes a lot of control... yes," she erupts with laughter, "I'm the control freak."

Takahashi has described her work as "visual music". "It's quite an abstract collection," she says, "which is why I think of music, which is quite abstract, and now I'm at the stage when I'm composing."

And there will be music, of a sort, which will come from whatever sounds the machines can manage. "Everything will be plugged in and working in some sort of strange way. It's going to be fun."

And when it's all over? It will be photographed, filmed and drawn; the objects will be packed up, sent home, or put in storage, and the gallery will revert to a blank canvas - enough to make even the tidiest of minds cry out for a return to a little controlled chaos and confusion.

`Neurotic Realism', at the Saatchi Gallery, 98A Boundary Road, London NW8 (0171-328 8299), 14 January to 4 April