Update and revision of Ordnance Survey products

This page gives an overview of Ordnance Survey's policy for updating the products available in Digimap. The most up to date revision policy for Ordnance Survey data can be found on Ordnance Survey's website at: Click Here (opens in new window). The Digimap data update page provides information on when each product was last updated in Digimap.

Ordnance Survey revision policy

Ordnance Survey have created and continue to maintain the National Topographic Database. This Database is their record of the topographic features in Great Britain at any time. All of their map and data products are derived from this database. Ordnance Survey revise the database to reflect changes in the real world, and in doing so apply a series of priorities. For these priorities, Ordnance Survey categorise change into a number of different categories. The table below describe these categories.

 

  Landform examples OS revision policy
Prestige Sites
  • community sites (bus stations, hospitals, schools etc.)
  • retail developments
  • new transport routes (road and rail)
Captured before they are open to the public.
Category A
  • new developments (residential and non-residential)
  • new or significantly changed roads, railways, canals, airport runways
  • coastal zone erosion and deposition
  • major landscape changes (e.g. landfill, quarries, forestry, reservoirs)
Within six months of completion.
Category B
  • small changes to built environment (e.g. construction of garage)
  • changes to tracks, paths, private driveways etc.
  • watercourses
 
Captured with changes to Prestige Sites and Category A changes, plus in rural areas captured as part of the MasterMap Imagery Layer program.
Category C
  • extension to residential buildings
  • street furniture
Only captured when directly associated with changes to Prestige Sites, Category A or Category B changes.
Tidal Data   Significant changes to tidal data are captured within 12 months of being made aware.
Archaeological and antiquity information New archaeological and antiquity information, and revisions to existing information, is supplied to Ordnance Survey by a number of national heritage bodies. Within six months of receipt of the information from the heritage bodies.

Continuous revision

Continuous revision is the process currently undertaken to capture major changes in the landscape such as large housing developments, commercial developments and major road and railway construction. Continuous revision is applied equally to new construction and demolition. Changes are captured within six months of building completion or demolition.

Cyclic revision

Cyclic revision is the process of periodically updating changes to the natural environment that occur at a slower rate than in the built environment. Typically changes are captured through the use of aerial photography at fixed intervals.

Supply of Updates

To see the latest update dates for all Ordnance Survey products available in Digimap, click here.