Our height data and LiDAR products for site landscape and topography add up to the most comprehensive online range in terms of detail and coverage. Coverage is available for both the UK and Northern Ireland.
Easy to work with, the data can be brought into CAD and GIS software to enable 3D analysis and provide important contextual information for a range of applications.
Read our How to guide for how to buy Height Data.
|Supplier||Various (see table below)|
|What’s it for?|| • Site analysis and planning
• Flood modelling
• Environmental impact visualisation
• Terrain modelling and visualisation
|Formats|| • DXF Format Points
• DXF 3D Face
• Erdas Imagine
• DXF Contours
|Scale / resolution||From 0.25m > 50m (see table below)|
In most cases an Ordnance Survey-based map or aerial imagery will be needed in order to relate the height information to geographic and topographical features.
When opened in CAD/GIS, all formats are geo-referenced with an x, y location (eastings, northings on the Ordnance Survey National Grid) making it very easy to precisely overlay height data with OS mapping products. In CAD, an insertion point of 0,0 will need to be specified if prompted by the software.
|Supplier||Dataset||Resolution||Vertical Accuracy||Coverage||DTM or DSM||Data Collection Method|
|Environment Agency||EA LiDAR||2m-0.25m||+/- 15cm||Coastal, flood risk and urban centres||Both||LiDAR and photogrammetry|
|Ordnance Survey||OS Terrain 5||5m|| +/- 1.5m Urban
+/- 2.5m Rural
|GB||DTM||Photogrammetry, topographical survey|
|Ordnance Survey||OS Terrain 50||50m||+/- 4m||GB||DTM||Photogrammetry, topographical survey|
|LPS||LPS OS NI||10m||+/- 1m||NI||DTM||Photogrammetry|
|Airbus Defence & Space||Astrium LiDAR||2m - 0.5m||+/- 15cm||100+ GB urban areas||Both||LiDAR|
|Blom||Up to 0.25m||+/- 15cm||London||Both||LiDAR|
|Cities Revealed||2m or 1m||+/- 15cm||Numerous urban centres and environs||Both||LiDAR|
DSM and DTM
Digital Surface Models (DSMs) provide a topographic model of the earth's surface. They measure the height values of the first surface on the ground as seen from above, including terrain features, buildings, vegetation and power lines.
Digital Terrain Models (DTMs) provide a topographic model of the bare earth / underlying terrain of the earth's surface and are usually derived from DSMs by digitally removing the man-made and vegetation features. The stated accuracy of a DTM will therefore usually be slightly lower than that of the DSM it's derived from, particularly in areas of continuous and dense building and tree coverage.