Dataset Overview
This dataset shows the suitability of domestic and non-domestic building rooftops for the installation of photovoltaic (PV) solar panels.
The domestic and non-domestic classification is based on the Ordnance Survey building classification, where properties classified as residential (e.g., detached, semi-detached, flats) are treated as domestic, and properties classified as commercial, industrial, educational, and other non-residential uses are treated as non-domestic. The following dataset description applies to both domestic and non-domestic properties.
The dataset takes into account the property type, roof size, roof surface information, roof orientation and the presence of existing solar panels to calculate the viable roof area, recommended array size (kW), estimated peak capacity (kWp) and estimated annual generation (kWh) of a PV array installed on the roof.
A roof is considered suitable for solar panel installation if it has enough usable space to support a minimum of a 1.5 kWp capacity system (approximately 6 PV panels) and has enough roof area facing a favourable direction: east, southeast, south, southwest or west, or is a flat roof. Flat roofs are always treated as suitably oriented, because panels can be mounted on frames angled towards the south regardless of the underlying roof direction.
Figure: Yellow shows a building suitable for PV installation, Grey shows a building that is unsuitable.
Methodology
This dataset is built directly from the Ordnance Survey National Geographic Database (OS NGD). The current model uses the roof characteristics already published within OS NGD, including roof area broken down by compass direction and by flat/pitched surface. This makes the assessment faster, more consistent across the country, and directly aligned with Ordnance Survey’s authoritative building records.
The dataset is developed from the following primary sources of data:
OS NGD Buildings: building geometry together with derived roof attributes, including roof area by direction (north through northwest), flat and pitched roof area totals, roof shape, solar panel presence and green roof presence.
OS NGD Address: used for determining building description, classification and property (UPRN) information, and for distinguishing domestic from non-domestic properties.
Non-domestic functional suitability lookup: a classification list used to exclude building archetypes that are not appropriate for rooftop PV (for example places of worship, petrol filling stations and safety-sensitive industrial sites).
Figure: Data related to roof attributes available in OS NGD
Each building is assessed in sequence, and exits the process as soon as it fails a check:
Data availability. if the core roof area inputs are entirely missing from OS NGD, suitability cannot be assessed and the property is flagged accordingly.
Building archetype (non-domestic only). non-domestic buildings are screened against the functional suitability lookup; ineligible archetypes are marked unsuitable. Domestic buildings skip this step.
Existing solar. where OS NGD indicates solar panels are already installed, the building is recorded as already deployed and is not treated as a new installation opportunity.
Shared-roof assignment. where multiple properties (UPRNs) share a single roof, the opportunity is assigned to one representative record (the parent or shell UPRN) to avoid counting the same roof more than once.
Usable roof area. The practical roof area available for panels is calculated by filtering out unfavourable (north, northeast and northwest) facets, applying spacing and margin allowances to pitched and flat roofs, reducing for green roofs, and excluding areas whose orientation cannot be reliably determined.
Minimum size gate. The usable area must support at least a 1.5 kWp system (approximately 6 panels).
Orientation gate. The roof must have enough favourably oriented area, unless it is a flat roof (which always passes this check).
Energy estimate. The usable area is converted into a panel count, a recommended array size, an orientation- and tilt-adjusted peak capacity, and an annual generation figure.
Assumptions
Roofs are considered favourably oriented if they face east, southeast, south, southwest or west (broadly 90° to 270° clockwise from north). Flat roofs are always treated as suitably oriented.
An average solar panel is assumed to have a capacity of 0.25 kWp and a plan area of 1.6 m².
A roof must support a minimum system size of 1.5 kWp (approximately 6 panels) to be considered suitable.
A pitched-roof packing factor of 0.75 and a flat-roof packing factor of 0.60 are applied to account for spacing, margins and roof furniture.
A green-roof allowance is applied where a green roof is present, to reflect the additional complexity of installation and maintenance.
A conversion factor of 1 kWp = 850 kWh per year is used to calculate the Annual Generation from the Peak Electricity Capacity (a conservative UK screening assumption; a location-specific value may be used where pvlib is enabled).
Buildings already reported as having solar are recorded but not counted as new installation opportunities.
Where multiple properties share a roof, the opportunity is assigned to a single representative (parent or shell) UPRN to avoid double counting.
Sources
Fields
Field Name | Field Description |
UPRN | Unique Property Reference Number. |
Parent UPRN | In a building containing multiple properties, this column provides the parent Unique Property Reference Number (UPRN) for the given child UPRN. |
UPRN Type | Classification of the building according to building topology |
Primary Code Description | Ordnance Survey Primary Classification Code. |
Roof Area Suitable for PV [m^2] | The estimated area of the roof suitable for a PV array. |
Roof Orientation from North [degrees] | The estimated orientation of the roof from North. |
Recommended Array Size [kW] | The maximum array size that can be installed on the roof. |
Peak Electricity Capacity [kWp] | The peak electricity generation capacity based on the size and efficiency of the array. |
Annual Generation [kWh] | The expected annual electricity generation of the PV array. |
Solar Presence | Indicates whether OS NGD reports existing solar panels on the roof. |
Overall Suitability |
The overall suitability of the property for rooftop PV.. |
Remark | Additional remark for suitability |