Some, but not all, all the conveyance drawings include dimensions but the written part of the conveyance often includes the qualification ‘or thereabouts’. As a result any dimensions that may be included should not be taken as gospel. In addition it should be noted that what the architect or designer intended and what the builder actually constructed may be slightly different. There is also the likelihood that the fences or other boundary features to the property have been replaced over time and may not have been put back in exactly the same place as the original.
Land Registry title drawings are also inadequate to precisely define the boundary location. These are clearly noted as providing the general boundary position rather than its exact location. You should also note that any measurements scaled from the drawings may differ from measurements taken from similar points on the ground.
There are a number of reasons why the Land Registry title drawings are inadequate to precisely define the boundary.
Land Registry title drawings are based on the Ordnance Survey data or which have been prepared and updated by a variety of means over time. The original Ordnance Survey data was prepared by hand following physical inspections of much of the country. Originally this was in imperial dimensions. This data has been metricated and digitised which may have caused some discrepancies. More recently much of the updated data has been obtained through the use of aerial photography and interpretation of this information to be shown on plans. As result of these factors the Ordnance Survey state that their data has degrees of relative and absolute accuracy depending upon whether this is an urban or rural area and the degree of confidence required for a specific purpose. In a typical urban area the Ordnance Survey advice that their data may have a relative error of less than plus or minus 0.5 metres over a 60 metre measured distance. This means that approximately half of measurements between OS points 60 metres apart will fall between 59.5 metres and 60.5 metres with the remainder falling outside these parameters.
Land Registry title drawings are usually prepared at a scale of 1:1250. This means that a 1 mm line (equivalent to a thick pencil line) on the drawings equates to 1.25 m (approximately 4 feet) on the ground. If the Land Registry plans have been copied or printed then this may add further distortion to the original data or making it increasingly difficult to scale from these.
For the reasons outlined above it is only possible to scale from any title drawings to the nearest 1.0 to 2.0 m’s (up to 6 feet) and certainly not down to the nearest few inches required for most boundary disputes.