I congratulate Ann Winterton on securing this debate and I hope to provide the clarification that she seeks. However, she posed some detailed questions about the legislation, which I accept were entirely appropriate, and I therefore undertake to write to her to ensure that in due course we cover all the points that she made.

We recognise the difficult problems that can arise when trying to find suitable accommodation for Gypsies and Travellers, and the hon. Lady will acknowledge that we take these issues seriously. We have been working hard and we will continue to work hard to find solutions to try to alleviate the distress to everyone concerned. The hon. Lady asked a number of detailed questions about the location of caravans in back gardens, and I shall attempt to answer them as fully as possible. However, as I said, I shall write to her in due course, because I do not think that I will cover every point that she made.

The hon. Lady asked to what extent the usage of a caravan would fall outside the definition of being

"incidental to enjoyment of the dwelling house".

A caravan is not a building. Stationing one on land is not itself "operational development" that requires planning permission, although associated works such as the provision of infrastructure and hygiene facilities may well be. Under planning law, householders can park caravans in their gardens or driveways indefinitely, provided that no material change of use of land occurs. However, in certain circumstances, the placing of a caravan on land may change the principal use of that land, which would amount to development in the form of a material change of use of land. It is for that reason that the use of land for an occupied caravan generally requires planning permission.

The hon. Lady asked whether adding extra caravans would still be incidental. A householder is entitled to use caravans as extra accommodation without planning permission, provided that the occupants continue to use the house, for example, the kitchen or bathroom. If, on the other hand, a caravan is there for another purpose not incidental to the enjoyment of the main dwelling, known as the dwelling house—for example, it is inhabited quite separately from, and independently of, the dwelling house—planning permission for change of use of the land would, generally speaking, be required. As it would result in the creation of a new planning unit, such permission may well not be granted in a residential area. If a caravan was being used in connection with a commercial purpose, the local planning authority may decide that an unauthorised change of use of land had occurred, for which planning permission should be sought.

The hon. Lady also asked whether there were any time limits relating to the stationing of caravans, and whether it is possible for more than one caravan to be sited without the need for planning permission. As I stated previously, caravans can be stationed indefinitely in someone's garden or driveway, provided that no material change to the use of land occurs. There is no legally defined limit on the number of caravans that can be stationed in gardens before planning permission is required. However, if so many caravans were stationed in the garden of a house that they ceased to be incidental to the principal use of that land, the local planning authority could require a planning application, or take enforcement action against the unauthorised change of land use.