Festive lights: Love thy neighbour's inflatable snowman?

It's time to sing again: "Deck the halls with boughs of holly/ Fa la la la la/ La la la la." But what if it's more than just the halls and holly? What about that house down the road with the garish Christmas lights on the trees outside? Christmas lights raise a smile but most of us breathe a sigh of relief when they find that no one is doing it on their road.

Putting Christmas bling on your suburban crib has become increasingly fashionable in recent years. "Orders from individuals have increased enormously. A typical home spends £150 on lights, but we have had households spending £5,000, which is what you'd expect a company to pay," says Fiona Cameron of www.xmasdirect.co.uk , one of the country's largest suppliers of Christmas lights.

"Outdoor lights," she continues, "are much more popular these days, and it seems they're especially common in Wales, Cornwall, Essex and London." Cameron explains that they used to be very specialised, expensive and involve complex systems using transformers. "But with lower-energy lights, you can run a large display from a normal household circuit," she says.

There are more than 50 outdoor lighting firms in the UK, most selling Christmas specials. Why not try a three-foot-tall illuminated polar bear for £279.99, a 3-D horse-and-carriage set for £399.99 (plus £70 for Santa sitting inside), or my personal favourite, an animated Santa and Snowman on a see-saw for just £136?

But not everyone is amused. Websites such as www.houseblinger.com encourage owners and neighbours to submit pictures of displays, asking them to vote for the best; www.uglychristmaslights.com celebrates the most tasteless examples.

Sometimes it can get serious. Vic Moszczynski used to festoon his house at Sonning-on-Thames in Berkshire with 22,000 fairly lights at Christmas for 18 years, until 2006, when neighbours won a court injunction. He was then restricted to 300 lights, four seven-foot-high inflatable cartoon characters, eight 30-foot-long strips of rope lights and two illuminations in the front garden.

Within a few months, paint had been daubed over the homes of three complainants and Mr Moszczynski found himself in court accused of vandalism, although he was acquitted when the judge found there was insufficient evidence to convict him.

There are hundreds of similar disputes every year. Planning permission is rarely required, even for large outdoor Christmas displays, because they are not permanent and do not change the footprint of the property. So rows tend to break out once the lights are up and the crowds arrive. "Disputes between neighbours can become very bitter and cause great distress for both sides. Mediation, whether informal or in the presence of lawyers, is often the best way to resolve disputes, as going through the courts can be emotionally and financially draining, says John Pugh-Smith, a London barrister who has written a guide on how to resolve disputes between neighbours.

The police, the Law Society, Citizens Advice bureaux, councils and mediation services all report sharp rises in numbers of complaints about light pollution, increased traffic, noise and even brawls caused by the spread of Christmas lights. Leonard Road, a street in Woolaston in the West Midlands, has more than 30 homes lit up and has more than 40,000 visitors each December; one Scottish residential street claims 3,000 visitors each weekend in November and December.

There's an environmental price to pay, though. The Energy Saving Trust says that modest indoor Christmas-tree lights, burning for 10 hours a day for two weeks, will cost UK households £15m this Christmas. "A home with a big outdoor display lit throughout December and early January may spend the same as it would during six weeks of normal usage and generate vast amounts of carbon dioxide," says a spokesman.

But the trust has thrown out a lifeline. It advises using LED Christmas lights, which use just 10 per cent of the energy of conventional festive bulbs. There is no guarantee that the lights won't be tacky and annoying to neighbours, but at least you can't be accused of not caring about the environment.

Ding-dongs: Quarrels of Christmas past

* In Ayrshire, 50 residents got an injunction limiting a neighbour's 8,000-bulb display to three hours a day

* Robbie Raggio, a Sussex businessman, received anonymous letters describing his charity lights in Hove as "distasteful" and a "wasteful use of power"

* Middlesbrough Council stopped the owner of a light-strewn house from erecting signs diverting traffic into her street

* A residents' association in Utah has complained about noise and lights from one house that put up Christmas decorations in July