OS MasterMap Topography Layer upgrade 2016

From autumn 2016 we'll be upgrading OS MasterMap Topography Layer with improvements to delivery, new styling options and content updates.

The upgrade will be happening in seven stages:

  • Delivery upgrade including schema update
  • New content to be delivered in six stages on a six-weekly basis after initial delivery upgrade

The new delivery upgrade will simplify the delivery and file management of Topography Layer. At the same time the new schema being delivered will enable the new content, which will have 76 new descriptive term attributes, to give even greater detail.

Delivery upgrade

We’ll be upgrading the schema from version 7 to version 9 so new descriptive terms can be released. The fulfilment of Topography Layer will be changing so we’ve taken the opportunity to simplify the files that are supplied with it. This means that:

  • The file names will be shorter.
  • Some supplementary files will no longer be supplied.
  • The disc contents and order details files will be merged into one file.

Please see the planned changes to fulfilment for more details.

Content upgrade

The new content will be delivered in six stages on a six weekly basis after the delivery upgrade. Each release will include up to three million feature changes, which will increase file sizes by around 30%.

We highly recommend that you take delivery of Topography Layer at regular intervals to keep file sizes manageable.

The proposed content rollout is shown below for guidance only (in brackets - an indicative number of features being updated):

  1. Agricultural land north (1.7 million)
  2. Agricultural land south (1.7 million)
  3. Land and structures (2.7 million)
  4. Rivers (1.6 million)
  5. Lakes south (1.6 million)
  6. Lakes north (1.6 million)

Enhanced descriptive terms

The content upgrade unlocks the descriptive terms of up to 11 million real world features for more precise identification and analysis, giving you:

Even more detail
The new, additional terms give a much greater set of attributes alongside existing terms. For example, the existing combination ‘Marsh Reeds Or Saltmarsh’ will be split out into three individual terms: ‘Marsh’, ‘Reeds’ and ‘Saltmarsh’ so you can analyse and use the data much more accurately.

Individual attribution for features
Customers can identify certain features by reading text on the map or searching within existing features. For example, two Posts may have been shown as two ‘point features’ on the map but with only one piece of guiding text saying ‘Posts’. Now, each individual point feature will carry the new term (in this case ‘Post’). This deeper level of data means you can search for the actual number of posts as separate point features enabling more precise analysis.

New descriptive group
The term ‘Structure’ has now been moved to the descriptive group attribute to enable structures to be individually identified. So, whereas before, a chimney, footbridge or tank would be simply called a ‘structure’, for example, these will now be termed individually as ‘Chimney’, ‘Footbridge’ and ‘Tank’ within the descriptive group of 'Structure'.

New descriptive term
The descriptive term ‘Agricultural Land’ will be a brand new feature introduced with the upgrade, to define areas of land with a main purpose of growing crops or keeping livestock. This, together with the additional foreshore and land-fill descriptive term attributes will make land use much clearer.

Coincident tide-lines
The new descriptive terms will take into account the fact that high and low tides may not be clearly defined in certain areas. For example, whereas on a shoreline there is a defined difference between high and low tide, in some places such as quays or docks the tidal range is co-incident and can only be measured vertically. The Mean High Water (Springs) term will appear with the descriptive terms for Mean Low Water (Springs) or other features such as Groyne or Building Outline, when co-incident, giving a clearer depiction of tidal range.

ITN changes

As part of the OS MasterMap Topography Layer changes, ITN is also set to update. This will come into effect with the delivery fulfilment only.

As with Topography Layer, the changes aim to simplify delivery and make file management easier, creating a smoother process for standard ITN updates.


To get the most out of the new content you will be able to style Topography Layer using the enhanced attributes to see even more detail at a glance.

We are introducing a number of new styling options for both current and upgraded Topography Layer including style sheets in SLD, LYR and QML.

These will be available in 2015 through the open source portal GitHub and fully supported with version control, user guides and release notes.

Styling resources:

Descriptive terms in detail

For software developers and customers with bespoke systems we’ve provided some resources to list the possible new descriptive term combinations below. These document also include a definition of each descriptive term so you can see the rules we used to collect the data and to help you to get the most out of the new detail.

This is still subject to further refinements, so please check back here for further updates. To let you query and compare the data with previous versions, all releases of descriptive term combinations are below.

OS MasterMap Topography Layer version 9 schema – new descriptive group and descriptive term combinations (Excel files except where stated):

Sample data

The sample data below, released in November 2014, is primarily for partners who make software and systems to translate OS MasterMap Topography Layer. This is simulated data created using artificial geometry and does not correspond to real world features.

We’ve been working closely with our partners and software vendors to  ensure they’re ready for these changes. If you use a third party software to translate your Topography Layer, your provider should modify their system to accommodate this update.

However, if you’re a customer creating your own software or systems to translate Topography Layer, this change could affect you, and you’re advised to test this sample data in your systems. We’ve been rolling out beta sample data directly to Topography Layer customers and partners throughout summer 2015.

This data should not be loaded into your current Topography Layer data holding as it will invalidate verification of your holding when using a Feature Validation Data Set (FVDS). It should only be used in a test environment.

If you are an existing customer of Topography Layer, beta data is available for testing. The area covers Southampton and Isle of Wight as this area has all of the new descriptive terms. Access to sample data can be requested through your account manager.

Sample data resources: