builtstructureheightconfidencevalue

This code list is used in association with the Height Confidence Level attribute which is present within the Building Feature Type, Building Part Feature Type and Structure Feature Type. The code list provides a qualitative assessment of the confidence value in the height attributes.

Please note that the label definitions below were refined and updated in February 2025 to reflect recent height data improvements.

Label	Definition
High	Buildings and structures that have been manually heighted, for which we have high confidence in the accuracy of the values.
Incomplete	Buildings and structures that have been automatically derived by Ordnance Survey's height algorithm for which we have not been able to calculate some or all of the height values, either because they were still under construction when they were heighted or because they didn't meet the expected quality level. Where values have been aggregated (for example, the Building Feature Type), this value indicates that there was one or more source features with a confidence level of ‘Incomplete’.
Low	Buildings and structures that have been automatically derived by Ordnance Survey's height algorithm, for which we have a low confidence in the accuracy of the height values because they have had their geometry altered since their height values were last extracted.
Moderate	For height values applied to the majority of buildings and structures, with values automatically derived by Ordnance Survey's height algorithm, following the normal process, where nothing downgraded the confidence to ‘Low’ or ‘Incomplete’.
Not Assessed	Buildings and structures for which the confidence of the building / structure height values has not been assessed.