Many land owners are surprised to discover that Land Registry plans do not define the exact line of a boundary. They are very often based on O.S. mapping that uses a single line to delineate a boundary feature that may be several metres wide (such as a hedge) and are also subject to the O.S. accuracy which is defined as 1.0m for urban areas and 2.5m for rural areas. The plans only give an approximation of the location of the boundary. These plans are therefore referred to as showing general boundaries.
In order to define the exact location of a boundary, the deeds of the property can be consulted to see if there are any plans that were drawn up to a recognised scale, with dimensions appended or if there are any descriptions of the boundaries in historic conveyancing documents. If these do not exist then the only option is to look at what is on the ground and work out who owns the boundary features, such as walls, hedges, fences etc so that an accurate plan can be surveyed and drawn up. This process is made a lot easier if the landowners on both sides are in agreement!