The Geospatial Commission’s official announcement to release core identifiers under Open Government Licence mandated by the Open Standards Board is welcome news for many, especially here at Connected Places Catapult where we are looking into use cases for these newly accessible UPRN.
Recently our work has focused on how UPRN’s are created and managed, so we thought now would be a pertinent time to share our findings on the process of creating a UPRN, and how this will hopefully inform their use moving forward.
What is a UPRN?
A Unique Property Reference Number (UPRN) is: The unique identifier for every addressable location in Great Britain – Geoplace
UPRNs are administered by Geoplace who collect this information from local authorities (LA). A UPRN is simply a 12 digit number with an associated address and coordinate pair (longitude and latitude). This number refers to a Basic Land and Property Unit (BLPU), which can be anything with a UK address.
“BLPU is the premises, property or thing, the conceptual space a UPRN identifies.”
Paul Downey, Head of Digital Land at MHCLG. Originally posted on Twitter.
This makes UPRN’s even more granular than postcodes, as one postcode may refer to multiple flats in a block, whereas each distinct unit would have its own UPRN.
Prior to this announcement UPRNs were under a restricted license that made them “open but closed”: which is to say that they were free to use, but restricted from use in conjunction with other Ordnance Survey data or in any other third-party commercial product. As part of this announcement Ordnance Survey have replaced the previous TOID and UPRN policies with a single, unified policy for all OS identifiers. And now these identifiers sit under the Open Government Licence they are free to:
- copy, publish, distribute and transmit the Information
- adapt the Information
- exploit the Information commercially and non-commercially, for example by combining it with other Information, or by including it in third-party products or applications.
How are they distributed
Geoplace controls and stores all of these of unique numbers, and distributes batches of these numbers to each local authority with one simple instruction:
“give them back to us when they have an address and longitude/ latitude coordinates”
It is then up to each local authority how they manage this process. As new dwellings are built, they will need addresses (maybe even new streets) and the location of these addresses will need to be mapped using coordinates. Local authorities then return assigned UPRNs to geoplace on a weekly basis, also informing the post office and emergency services of the new dwelling as well.
From unique number to UPRN
It’s important to note that the batches of numbers that Geoplace sends to LAs are just that – numbers. They do not become a UPRN until the local authority attaches the location data. When Geoplace receives this weekly update (from all local authorities), they then validate this information through a set of checks to ensure accuracy.
Local authorities face fines if their data isn’t good enough (point-coordinates need to be in the right place and the address needs to be correct). And an annual awards ceremony recognises the best data quality for every local authority.
Identifying a moving target
A unique challenge in creating an identifier like this, is that the entity (the BPLU we mentioned earlier) changes form throughout time. As per the geoplace guidance, a UPRN should be the:
consistent identifier throughout a property’s life cycle – from planning permission or street naming through to demolition.
This is important. A development can change a lot from what was planned to what is eventually built. A two-bedroom apartment may become two one-bedroom apartments. We need to be able to accommodate this change when managing UPRNs. An ability to reliably track, measure and audit this trail has multiple use cases:
- DWX embarked on an alpha focused on monitoring affordable housing. Sometimes however these planned affordable units aren’t built, and the tenure is flipped. Identifying a unit from the planning stage would allow tracking of the unit.
- Tracking a building from planning has also been highlighted in the Hackitt Review, the Building a Safer Future public consultation, and now as a priority for MHCLG
- Connected Places Catapult is working with Waltham Forest to help accelerate housing, identifying changes in the UPRN assignment process that will allow a shared view of a developments progress
- The ODI has identified an opportunity to link key datasets, such as energy performance certificates (provided by MHCLG) with price paid (provided by Land Registry).
As a result, many have looked to the UPRN as the “golden thread” of housing that provides a consistent identifier throughout the whole of a building’s life cycle. Despite all the noise around UPRNs at the moment, a key challenge identified here at Connected Places Catapult through various projects (such as exploring automation of housing monitoring in Waltham Forest) is that it is rarely the case that UPRNs are implemented from planning permission as Geoplace states. Because of the changes and constant updates to plans, some local authorities will wait until the plans have “settled down”, often much later in the development process of a new scheme (eg. following a request for street naming and numbering when a development is nearing completion). Although this seems a reasonable approach, and requires less updating of the UPRN information and reduces submission of out of date information that will be marked down by the Geoplace checker, in reality it means information about the development “goes dark” in this period – and in allowing this to prevail, we break this “golden thread”.
The Lifecycle of a UPRN
Just as a development changes, so must its identifier. This is where we get to the lifecycle of a UPRN. Like most things in life, the journey starts with planning. Planning identifiers will be assigned to all manner of things: new houses, new flats, new extensions on existing houses, and more. All will be given a planning ID, but not all of them will need a new UPRN. Nor will all approved new BLPUs be built. Our research suggests that as a local authority, if we took the planning ID, assigned a UPRN, and sent it to Geoplace to be marked – we would get a Fail for data quality. It isn’t technically “there” yet. Additionally, for larger sites, developers do not request new street names until later on in the development process, so we couldn’t give the UPRN a valid address. A definite Fail from Geoplace.
But we would be able to track the development internally if we could assign a Provisional UPRN. Referenced in section 3.2.14 of LLPG and SN&N Data Entry Conventions and Best Practice for the NLPG handbook, “Provisional” means the UPRN will not be exported to Geoplace in weekly reports.
For example, in the case of a new house:
1. Planning is approved with associated Planning ID
2. Match Planning ID to a UPRN number that Geoplace has provided
3. Set the status to Provisional
4. Wait until it has been built
5. Change Provisional to Approved
Export to Geoplace
Whilst simple enough for one dwelling, things do however get a little messy for developments with multiple addressable objects/ BLPUs – a block of flats for instance.
Each unit in a block of flats will need its own UPRN, but the “block” itself will also have a UPRN. This “parent” UPRN will look exactly the same as the unit UPRNs as they are all coming from the same batch sent by Geoplace.
In this set up, when tenures or the number of bedrooms change during the development, it can be handled very easily by throwing away a provisional UPRN for a new one. Tracking from this early stage will also allow us to collect data on safety inspections at a unit level. Essential to this is the provision of unit level data early on in the process – something we have been working with the LDD team from Atkins on by way of an Accommodation schedule.
The final stage in our UPRN life cycle is then retiring an existing UPRN. This may be the result of demolition of an existing building at which point the old identifier is retired and Geoplace is informed.
As the implementation outlined above is put into practice to varying degrees across England’s local authorities, one thing remains constant: all report to Geoplace. This is how Geoplace has been able to create this single source of truth megastore of all addressable objects in Great Britain. Until now this has not been open, resulting in an industry based around approximating and upselling this data. With the changes announced, these resources (and more) can perhaps now focus efforts on understanding and improving the places we live.
It remains important to note however that not all UPRN’s are created equal. As is so often the case with administrative systems, processes that facilitate everyday tasks may actually hinder efforts to perform analytics. If we do not focus on when they are assigned (data generating process), then their true potential cannot be realised. We have found that few local authorities make use of UPRN’s until developments are near completion, thereby missing the ability to link key data generated during development. This key data, if properly linked, could be used to understand the impact of interventions, investment and policies in a place, as well as enabling sharing and re-use of data across departments.
But in the meantime, the UPRNs are out, and we’re excited to see what uses they have and innovations they bring.
Written by Yusuf Sohoye, Data Engineer, Connected Places Catapult