> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-downloads/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-downloads/products/buildings-and-infrastructure-portfolio/os-mastermap-topography-layer-building-height-attribute/os-mastermap-topography-layer-building-height-attribute-downloads.md).

# OS MasterMap Topography Layer – Building Height Attribute Downloads

## Header file

The header file for OS MasterMap Topography Layer – Building Height Attribute is available for download as a CSV file:

{% file src="/files/XsdWHRXMNf6yhk6yhWJu" %}

The OS MasterMap XML schema is available from the [application schemas page on the Ordnance Survey website](https://www.ordnancesurvey.co.uk/xml/schema/v9/index.html). Previous versions of this schema are available to download from the website, the most recent version is included below:

## OS MasterMap XML schema, version 9

* [OSAerialMetadata.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/OSAerialMetadata.xsd)
* [OSComplexTypes.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/OSComplexTypes.xsd)
* [OSDNFFeatures.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/OSDNFFeatures.xsd)
* [OSGeometryTopology.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/OSGeometryTopology.xsd)
* [OSImageMetadata.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/OSImageMetadata.xsd)
* [OSMeasures.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/OSMeasures.xsd)
* [OSOrthoMetadata.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/OSOrthoMetadata.xsd)
* [OSQueryResult.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/OSQueryResult.xsd)
* [OSSimpleTypes.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/OSSimpleTypes.xsd)
* [OSIMIngestionMetadata.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/OSIMIngestionMetadata.xsd)
* [OSIMProductMetadata.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/OSIMProductMetadata.xsd)
* [OSIMSupplierMetadata.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/OSIMSupplierMetadata.xsd)

## OpenGIS Consortium schemas

* [feature.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/feature.xsd)
* [geometry.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/geometry.xsd)
* [gml.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/gml.xsd)
* [GML 2.1.2 implementation specification](http://www.opengeospatial.org/docs/02-069.pdf)

## W3C schemas

* [xml.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/xml.xsd)
* [xlink.xsd](https://www.ordnancesurvey.co.uk/xml/schema/v9/xlink.xsd)

{% hint style="info" %}
The XML File Repository License, covering the terms and conditions for the use of all Ordnance Survey XML schemas, is made available through the [Terms and Conditions page](/os-downloads/resources/site-resources/terms-and-conditions.md) in the Resources section.
{% endhint %}


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