OS 1:10,000 Large Scale Mapping

OS 1:10,000 scale mapping - Mountain & Moorland

1:10,000 scale is the smallest of the 3 base scales used by the Ordnance Survey (OS) in producing their Large Scale Mapping products that cover the whole of Britain. This base scale has a more limited specification for data capture than the other two base scales in use, and incorporates a higher degree of generalisation. The landscapes surveyed by OS at 1:10,000 scale include: 

• Lowland agriculture, settlement, transport and industry – for example, farmhouses, steadings, hamlets, updated infrastructure, crofts and settlements

• Upland agriculture & industry – for example, wind farms, farms, whisky distilleries and managed forests

• Open moorland and mountain-scape - for example, Estates, salmon fishings and wind farms.

Applications received by RoS for registration that fall within this mountain and moorland setting, or 1:10 000 scale mapping, are often high value, high profile casework; for example, large estates or wind farms. Often, these applications are also very complex; for example, they comprise large estates with numerous exceptions, or include salmon fishings or leases of sporting rights. Some, however, are registrations of single houses or crofts, and although small in size they can be tricky for us to map correctly onto the 1:10,000 base scale map. It is very important that we get it right for both the applicant and the Keeper since protecting the individual's rights, and the Keeper's warranty and reputation, are vital for the integrity of the land register. So although we receive smaller numbers of applications in these areas, they are, nevertheless, extremely important. 

1:10,000 scale OS coverage in Scotland

Coverage of 1:10,000 areas in Scotland is shown coloured orange in this image. 

63% of Scotland is affected by 1:10,000 scale mapping but, to date (2014), only 1% of registered titles (approximately 11,000 titles) are within these areas. (Updated figures have been requested and this will be updated when available.)

1:10,000 Scale OS Details

These specifications result in a generalised map appropriate for viewing at the base scale but which can lead to problems of understanding when compared with deed plans prepared using modern technology, where surveyors can prepare very high quality plans using GPS.

1:10,000 Scale OS Map Generalisation

Cartographic Generalisation is the process of simplifying and improving the legibility of maps with the aim of improving legibility. Generalisation is used to emphasise, simplify, select and sometimes omit features to produce a cartographic representation of the landscape at a scale of 1:10,000.

Transition between map scales - specification comparison

In this image we see an example of where a 1:10,000 scale map meets a 1:2500 scale map. The process of blending one specification into another at the edge of the two differently-scaled maps is known as "feathering".

Points to note -

• The river has changed from single line on the 1:10,000 scale map to a more detailed double feature on the 1:2500 scale map

• The roadway which is hugely exaggerated on the 1:10,000 scale map to make it clearly visible when viewed at base scale is now more representative of the actual width on the ground on the 1:2500 scale map.

If feathering affects your application, consideration should be given to whether or not it affects your ability to accurately reflect the legal boundary. If it does prevent you accurately mapping the legal extent (within the published tolerances), you should discuss with a Plans HEO or Plans SCW if it is appropriate to submit a Form P24 survey request for the area. See here for advice on completing the P24 form.

What do I do if the deed plan is more detailed than the OS 1:10,000 scale map?

Sometimes an applicant will submit a deed plan that is sufficient to identify the property but it cannot be reconciled with the features on the OS 1:10,000 base map held by the Keeper. An example could be a rural property where the OS base scale is 1:10,000 and is not generally up to date. The deed plan submitted by the applicant has been produced at a larger scale and shows more up to date detail that cannot be reconciled with our version of the OS map.

If after discussion with a Plans HEO or Plans SCW, it is decided that the application cannot proceed using the 1:10,000 base map held by the Keeper, a Form P24 survey request should be made to Mapbase Maintenance (see here for advice on completing the P24 form). Once the P24 has been submitted, the application should be held until the survey results are received. This usually takes around 2-3 weeks for mainland Scotland, but can be longer for the islands.

Possible future update to the OS 1:10,000 scale map

The upgrade of 4.1m RMSE specification areas (1:10,000 scale) within OS large scale mapping has been discussed on/off since circa 2016 and deemed of value however the impact and challenges of implementing it in many customers systems and services, including RoS, have meant this programme was put on hold indefinitely.

Initially the OS looked at upgrading the survey specification of the lowland areas only, which would catch most agriculture, settlement, transport and industry areas (these tend to be higher density areas within the rural mapping environment). However engagement with customers, particularly RoS, has indicated the preferred option to be a complete upgrade of all 1:10,000 scale mapping to either the rural specification of 1:2500 scale or in some cases even the urban specification of 1:1250 scale. The OS have intimated that this is their likely option, should the programme go ahead at some future date. 

One specific and major impact of the possible OS upgrade on RoS would be the updating of the registered titles we currently hold and a designated team would be required to update all the impacted titles which, although the number of them would be relatively small, would be of a more complex nature. However, the potential benefits of the upgrade would be considerable, with the mapping in the 1:10,000 scale areas seeing a large improvement in terms of both currency and specification, and making it easier for RoS to reconcile new large scale surveyors' plans with the OS base map.