A new look for your house? You need a good scrumbling!

Or maybe you want a fake marble floor using synthesised 17th Century paint. Whatever the case, says William Raynor, you don't always have to spend a fortune to get that natural effect. But then again...

It all depends, of course, on what you call "natural". But, in these days of increasing environmental consciousness, the growing desire for so-called natural products is as obvious in people's homes as on supermarket shelves.

But as fashion tends to be more about style than substance, and as using certain natural substances - such as mahogany and greenheart or other tropical hardwoods - is as becoming as ungreen as chewing rhino horn, there is often a line which needs to be sensibly drawn between surface looks and material realities.

"There are natural looks and natural looks ," says Caroline Cox who, as a relocation manager working mainly in London, sees many variations. "There's the Tuscan look and the gothic look, to mention just two, and the point is that within their different contexts, different things can look natural in different ways."

She often suggests to clients, even before she's found them somewhere to live, that they make up a collage from interior design magazines and catalogues of what they want, room by room. "It's like a story-board for television or film," she says. "They can make up their own 'sets' for the person they dream they are or would like to be, and also get the visual impact of the kind of posh interior design other people have paid a fortune for. Do they see themselves wandering around the kitchen in a Laura Ashley nightie eating muesli, or in leathers cracking a whip?

"For the Tuscan look, they can do things like paint Cuprinol on new plaster. If they're going gothic, they need to go to architectural salvage yards or get stuff from junk shops which they can distress with candle wax and eggshell."

She makes it sound so easy. But some looks require rather more hard work. "You've got to comply with party wall and building regulations, but you don't need planning permission to take half a ceiling down, put in a galleried sleeping or work area, a wood floor, some simple down- lighting, or to paint everything white."

But, she warns, beware of one particular downside. "The thing even these people with their natural good taste forget all too often is the bathroom, with that lovely, natural avocado suite which is going to be so essential but troublesome to remove."

Not much you can do with that when you've replaced it with good old white except cart it to the tip.

In the bathroom though, and in other rooms, there are other articles and materials which can nicely marry the desire for natural looks with eco-friendliness. Take, for instance, medium density fibre board (MDF), made from timber waste and by-products. Not only are there companies now selling all sorts of inexpensive carcases [furniture skeletons] made from MDF, but these can be transformed into pieces which can look old and natural and very expensive, indeed.

"If you're young or recently married or can't afford spend a lot of money on things like antiques, carcases like this can be just the answer," suggests Emma Mountain, who took a correspondence course in interior design, followed by a four-day taught course on paint finishes.

Emma paid pounds 125 and pounds 250 respectively for the courses which she found in the small ads in interior design magazines. She admits that many of the techniques she learned - ragging, stippling, sponging, dragging , marbling, stencilling etc - she could have learned from the standard books. "[However] apart from a marvellous hobby which one day might turn into something more," she says, "what the courses provided me with was a lot of practical tips and ways of avoiding some of the costly trial and error." Some of the best tips she picked up on her courses were:

If you've made up a glaze and you want to "finish" a large area like a wall, you'll need two people, one to apply the glaze, the other doing the paint effect before it dries.

If you're doing up a piece of junk furniture, don't strip it - just give it a good sand down to stop any peeling and clean it with white spirit.

If you're doing a "proper" job, always use trade eggshell - it's better quality.

Whatever you do with paint effects, don't overdo it, because the final result won't fit in naturally.

One of the effects she admits she hasn't mastered yet is scrumbling, the sort of old-fashioned trompe-l'il finish found in gypsy caravans and canal narrow-boats. With scrumble, and by painting your own grain and knots, you can rescue old wood floors that are too damaged, wormy or thin for the heavy sander. You can even disguise MDF by doing the same but then painting your own lines to create false boards and adding the odd nail hole.

Although the exercise would be fairly time-consuming, there would be certain advantages: you'd save yourself the trouble of "caulking" - putting a mastic or seal between the boards, as might be needed on a ground floor to stop drafts; and you'd have a floor less volatile or prone to expansion and contraction than many "genuine" ones.

Of course you'd know, even if no-one else did, that your wonderful natural floor was not quite natural after all. And besides, without the natural unevenness of real boards, it wouldn't feel quite right.

For the real thing, if you're going to abide by the dictates of your eco-conscience, you may well have to seek advice from eco-sources about where to find suitable eco-sustainable supplies - and sacrifice an arm and a leg to get the floor of your dreams.

Whether just sanding and/or caulking your natural floor, or creating it with scumble, you need to remember that without the fitted carpet you've just discarded, you won't easily be able to disguise any damage you do to the edges : so make sure all central heating pipes and electrical cables are already channelled underneath.

Then, having saved on the new fitted carpets - almost worthless when you next move - you can think about getting some rugs, which may well appreciate in value, and you can take with you when you go.

"For as little as pounds 100," says Jenny Hicks Beach, who deals in antique and semi-antique rugs costing up to pounds 5,000, "you can get a five-foot- by-three Baluch from the 1920s whose pile has gone but which still looks pretty. And for pounds 500-pounds 1000, you can get a semi-antique rug, either kelim or pile, Turkish or Persian, which will be a joy to possess and almost certainly a good investment."

To stop it slipping, make it wear better, and give it a bit of bounce and extra sound-proofing, she advises, back it with slightly smaller bit of carpet felt or rubber underlay. And if you're thinking of buying it at an auction, "avoid the carpet mafia!"

And if they've already skinned you, you can always be really creative, equip yourself with concrete slabs and a set of the kind of synthesised, lead-free, natural "16th-19th Century" colours you can get custom-mixed at small shops like London Decorations in Fulham, and turn your floor to marble.

"I could do that ," says a friend who's a gifted amateur, "and I promise you wouldn't know the difference."

Now there's a thought. And while he's about it, perhaps he might produce some "natural" terracotta tiles for the floor in the Aga-room, too.