When you wish walls would come tumbling down - on the neighbours

All too often, boundary disputes mean war with the people you live closest to. There's a way to stay friends over the garden fence, says Richard Phillips

It Starts over something trivial but before you know what's happening, it has escalated into full-blown confrontation. Months of hostility and stress all too often culminate in a court appearance that costs both parties thousands in legal fees. And, forever after, neighbours are enemies.

Boundary disputes are a nightmare in waiting for any property owner. One traumatised victim of a dispute so gruelling that he decided he had no option but to up sticks and move, paid hundreds of pounds to avoid repeating the experience. He hired a private detective to check out his prospective neighbours and the exact description of all adjoining fences and walls before he would commit to his new home. Once bitten, he considered it a small price to pay for peace of mind.

And with a court case costing pounds 7,500 a day on average, the financial cost is as fearsome to most as the emotional damage.

So how do these conflicts start, and what can you do to prevent them?

According to David Powell, chairman of the boundary and party walls panel of the Royal Institute of Chartered Surveyors, most boundary disputes "are about people". An unthinking neighbour can spark a dispute by taking a simple decision like, for example, deciding to lay a garden patio. Imagine if to do so he needs to temporarily remove the garden fence that separates his house from yours, and that he decides it would be easier to wait until you are away on holiday rather than asking your permission. On your return you find the fence restored - two inches further into your garden, and leaning at an angle.

The best defence against such manoeuvres is to be forearmed, and that means having precise evidence of the layout of your shared walls and fences. Mr Powell says photographs are the best, most conclusive proof of the layout of a property as it it was when you moved in. Preferably take the photo from an upstairs window, looking down, and you should take a new set every year - a good time is in late autumn, when the leaves have fallen from the trees.

A new area of dispute is the shared driveways on housing estates. A driveway may split into three, for example, and determining exactly where communal ownership ends and private ownership begins can be a problem. The solution is to make sure you know precisely where any boundary lies at the time that you buy a new home. It should be mapped out in the plan which accompanies the deeds. Mark it out on the ground in chalk then talk to the neighbour to confirm that they agree the line is in the right place. If not, don't buy the house until the matter is settled. Once the neighbour confirms it is right, take a photo of it.

It is just as important to have a complete understanding of shared boundaries when buying an existing property. These should, again, be stated in the text of the deeds, and laid out clearly in the accompanying plan. If the plan shows a T lying inside your space and next to a wall or fence, it means you have responsibility for its upkeep. However, this indication is null and void if there is no mention of upkeep in the text or if the text is ambiguous.

Lindsay Cuthill, a director of residential sales at London estate agents Savill's, urges purchasers to iron out any ambiguities before completion. Most estate agents will, he says, recognise a potential problem when they first view a property, and should be able to sort out any difficulties before it comes to be sold. However, if this has not happened, then common sense is the best way to proceed. "Far too often I have seen a purchaser turn down a property they otherwise adore, because of some minor irregularity in the deeds," he says.

He urges buyers not to resort to communications through lawyers. Far better that vendor, buyer and a chartered surveyor meet on site and hammer out the differences face-to-face, he says. If needs be, the lawyer for the buyer should also be present. Usually some sort of agreement can be forged in this way in a couple of hours. After that, it is simply a matter of having the deeds - and plan if needs be - altered in accordance with whatever was decided. Mr Powell adds that any such changes should also be notified to the Land Registry.

Even if you appear to have sorted out any contentious areas in the conveyancing, read the small print of your buildings insurance carefully. Most policies have a clause which allows you to reclaim expenses on a boundary or access dispute, where a chartered surveyor or lawyer has to be brought in by one or both sides. But excess charges can vary, and not all policies include such a provision as standard. If you're adequately covered and the worst does come to the worst and you end up in court, you may be able to recoup your costs. The best way to avoid such an outcome, however, is still to ensure you have conclusive evidence to back up your claim.

Disputes over where boundaries should lie are not the only potential problem. Another occurs where structural defects appear in a party wall. In this case there is a distinct advantage to living in London, which has its own laws to settle boundary disputes and related access problems. The London Building Act of 1939 broadly covers the area formerly overseen by the Greater London Council. Among its provisions are measures to resolve access disputes. If, for example, you need to underpin a shared wall, you or your builders will require access to the next door property. Under the LBA, each side can appoint a chartered surveyor who will determine what is the cost to the neighbour. He or she should then reclaim this from their buildings insurance. The insurer will reclaim its losses in turn from your insurer.

One of the main benefits of the LBA is that a neighbour cannot refuse access for important works to an adjoining property. This has been a frequent problem outside London where there have been no similar procedures recognised by the courts. If you are unlucky enough to have a churlish neighbour, he can legitimately deny you access onto his property, even if your home is slowly collapsing.

The problem was partly overcome by a piece of legislation in 1992 dealing with access to adjacent properties. Ironically it is effective in part because of its ferocious complexity and poor drafting. Few if any test cases have come to court, but it provides an effective weapon. If your lawyer threatens to take your neighbour to court under the 1992 Access to Neighbouring Land Act, his solicitor is likely to urge him to comply with your request for access.

Happily such methods should no longer be necessary after 1 July, when the Party Wall (etc) Act comes into force. This will extend the provisions of the LBA nationwide.