Listed building and their outlines

[colmjude]

Listed buildings and their outlines

In the United Kingdom, a listed building is a structure of particular architectural and/or historic interest deserving of special protection.

A listed building may not be demolished, extended, or altered without special permission from the local planning authority.

Guidance explaining process of listing a building.
Legislation for listed buildings.

What we have done

We have drafted a specification called Listed building outline. We are currently piloting this standard (read the publisher guidance) and have around 8 providers publishing data that we collect.

For this we needed to create a listed building grade dataset. This is category data that publishers should use to classify each building recorded.

We also collect listed buildings from Historic England. This is point data. Eventually, we'd like to consolidate the 2 datasets.

Why

Buildings designated as a listed building have additional planning restrictions, therefore it is important to know early if a property is a listed building, who designated it as a listed building and what that means in terms of restrictions. We think accurate, up-to-date and linked data records will help with this.

What we're looking for

We'd like to know more about:

• who needs listed building data? who is asking for it?
• what do they want to use it for?
• what should the data include? Does the standard cover that at the moment?
• how would you improve the standard?
• anything else you think we should know about listed buildings

[colmjude]

Historic England have recently published their Listed Buildings data as polygons.

We had a conversation with them and they said this data should include polygons for all listed buildings listed or amended since April 4th 2011. Buildings listed before this date might not have a polygon, in this case, it will still have point data.

[colmjude]

We've noticed quite a lot of the polygon data is made up of records with small triangle polygons. For example, here are some listings by Stockwell Park Road.

We think this might be when Historic England don't have the complete polygon data for the building.

Listed buildings is an excellent example of a dataset where we expect to collect data for a single entity from multiple sources. For example, to get the highest quality, most complete list building data, we will need to collect data from Historic England and Local Planning Authorities. In these cases, we need to work out who should be the primary source of the data, who is the secondary source and how the planning data platform should represent this.

[mattlucht]

We're proposing to make some changes to the listed building outline specification . Any changes that we make we'll ensure are backward compatible with any existing data.

• add documentation-url

[mattlucht]

Hello!

We've had a couple of questions about why we're currently collecting listed building point data from Historic England but also asking LPAs funded via Open Digital Planning project to provide listed building outlines.

As a bit of background, when we first started working with Open Systems Labs and the initial pilot LPAs the only data available from Historic England was their listed building points. This was problematic for PlanX in scenarios where a terrace of buildings was listed and the point data was in the middle of the terrace – if an application was made for a property at the end of the terrace then using the point-based data no listing was being returned. For that reason, LPAs were providing an outline of the listing.

Fairly recently Historic England have started publishing a listed building polygon dataset which looks really hopeful, and will potentially mean that we can get both the point and outline data from one place, removing the ask on LPAs.

However, initial analysis showed that the listed building polygon dataset isn't complete across LPAs and for now at least we may need to continue to ask LPAs to provide their outlines.

We're keen to have a conversation with Historic England to explore this dataset a bit more with them, and to also understand their process for creating the outlines.

In the meanwhile it would be great to hear if anyone has any thoughts or insights into this.

[greg-slater]

Hey @mattlucht, I've got a question around what area data providers should be expected to supply data for. There are some instances of data on the platform where the data provider has supplied listed-building-outline geometries which are within its Local Authority District boundary but beyond its Local Planning Authority boundary (these two boundaries can be different when the LAD contains a national park area or a local development corporation which is also a Local Planning Authority).

One example is Great Yarmouth. Quick example map below, with the LPA boundary in green, LAD boundary in blue, and listed-building-outline records in red:

It would be great to understand in these situations where there are multiple LPAs within a single LAD who is expected to provide data. Note: Great Yarmouth also have this same situation for article-4-direction-area data.

[mattlucht]

We've had several questions from LPAs regarding the data we're collecting around listed buildings and the role of Historic England.

Earlier this week we met with Historic England and would like to propose the following approach:

Data from Historic England

We'll collect the listed building point and listed Building polygon data from Historic England. This will form our listed building collection on planning.data.gov.uk.

Historic England are the authoritative source of the listing and its location.

Data from local planning authorities

To support the needs of planning software, such as PlanX, we will require the outline of the listing (also known as the listed building curtilage). This will form our listed building outline collection on planning.data.gov.uk

Next steps on this...

• we'll update our guidance to reflect this
• we'd like to know whether the name listed-building-outline makes sense, or would listed-building-curtilage be more useful?
• we need to clarify with HMLR their data requirements for listed buildings as considered as a local land charge

[kieranwint]

OS Update

Hello!

We’re aware it’s been a little while since we provided an update on the situation regarding Listed Buildings.

As of last week, the Ordnance Survey have updated their website on what data is acceptable under the terms of presumption to publish, which can be seen here under the “planning” sub-heading.

We think that this update, stating that a “listed building curtilage extent polygon including depicting the extent of a single property boundary” falls under the presumption to publish terms is a big step in the right direction.

In terms of how we got there, after a conversation with Historic England, we understood that we are asking LPAs to provide listed building curtilage as this is what is needed for planning, and the difficulties that this brings (as a standard definition simply doesn’t exist).

Our current understanding of curtilage is that it is the whole area impacted by the listing in the planning process, and there are a few different factors that play into how far the curtilage reaches. After learning this, we put our interpretation to OS, who then updated their website.

At the same time, we know that HMLR are requesting similar data for the purposes of their LLC register, and so we are working closely with them to try and reduce the burden on local planning authorities.

If you have any thoughts, questions, or concerns about any of the above, we’d love to hear from you!
You can also find all of the information we have gathered through our data design app.

[MrMikeRose]

For the last few months we have been running a 'working group' with a selection of funded LPAs to continue to develop our position on Listed Buildings.

We have been working to navigate 3 needs / requirements for listed building information.

1. Heritage Need - there is a listing and this is what is listed
2. Conveyancing Need - there is a listing and this is the property impacted
3. Planning Need - there is a listing and this is the area that is impacted

The Heritage Need is 'owned' by Historic England. The listing process of a heritage asset is theirs, they produce an open dataset relating to that listing. This is available as points and for some listings polygons. This is not suitable for planning decision making but can be used as indicative.

The Conveyancing Need is 'owned' by HM Land Registry. They have produced a standard for data to be provided to them by local authorities to make up the statutory Local Land Charge register. This standard asks for listed building curtilage* outlines as polygons. This data is not currently shared by HMLR and similar to the Historic England data it could be used as indicative.

The Planning Need is 'owned' by MHCLG. We have produced a specification for data to be provided by funded Local Planning Authorities to go onto the planning data platform. Our specification asks for listed building outlines as polygons. For planning decision making we need the listed building outlines to be the curtilage* as per the Historic England guidance. In most local authorities we have spoken to (it might be all of them) this dataset doesn't exist as the curtilage for planning purposes is only assessed formally when listed building consent is applied for. This data would be expensive to collect as it is a subjective assessment (as per the Historic England Guidance) and often may require heritage experts to undertake.

_ NOTE - how HMLR and MHCLG defines Curtilage is different even though the same word is used!_*

The working group has been an essential step in the development of our understanding and approach to listed building data. We have made some decisions as a group about the best way to approach the need for listed building data in the planning process.

1. We will gather the Open Data from Historic England and put it onto the platform. We will make sure it is clearly named and we will make sure it is clear that the data is indicative for planning purposes. That is it suggests that there is a listed building and further information should be sought from the Local Authority. We will ensure that the caveats on use for planning decision making are clear.
2. We will align the HMLR standard requirements and the MHCLG specification requirements so that Local Authorities are being asked for the same data. We will identify where we are asking for additional data fields in the specification and consider our approach to these. We will continue to work with HMLR around the accessibility of this data and the appropriate data flow to minimise the impact as far as possible on local authorities.
3. We will produce further information on why it is difficult for local authorities to gather the planning curtilage information, this will be in part by us documenting and sharing the information gathered in the working group. We will be clear that the aspiration is that the data provided is the planning curtilage (ie following the Historic England guidance).

Through this process we have had some interesting discussions around the basis of the planning system, where it has been designed so that there is a human in the loop making decisions. In that, the legislation and guidance are deliberately fuzzy and in order increase automation of planning decision making processes such as defining the listed building curtilage need to become more binary.

We will be sharing the documents around the working group and our understanding of the 'curtilage question' soon.

[kieranwint]

Hi all - just to provide a quick update on where the data design team are with regards to the listed building specification:

• Based on the feedback we gathered from the previous working group sessions, we are currently working on factoring this into an updated and revised specification.
• We will be holding another working group session to present back the revised specification on Wednesday 23rd October at 11:00 - if you would like to attend please let us know.
• In the meantime, we are aligning the LLC schema and our specification to make things easier for LPAs however this will not significantly alter the data that needs to be provided - so please do continue working to provide data.

If you have any further questions please do not hesitate to get in touch with us.

[Jonathan-Thom]

Hi project team

Have just come across this project, while making a regular check on the digital planning landscape – participation in it appears to have been limited to the project team/some LPAs?

As a newcomer to it, it’s obviously difficult to comment on the detail of the project until I’ve had more opportunity to look at it.

As very general points, however, (i) effective digital planning is of paramount importance if the future planning system is to work effectively with the resource which will actually be available to it; and (ii) heritage being currently one of the least-effective areas of the planning system, its correct and effective incorporation into digital planning is essential – I would certainly have ideas on this.

If this project is to work, it will need the involvement of other stakeholders, including owners and consultants, as well as LPAs.

I might be able to join the 23 October meeting if that would be useful.

Jonathan Thompson
Senior heritage adviser, CLA (Country Land & Business Association, which has 26,000 members who look after at least a quarter of all heritage, and make many thousands of planning and listed building consent applications each year)
jonathan.thompson@cla.org.uk

[Jonathan-Thom]

This follows up my previous post, and covers a perhaps more immediate point, that these posts seem to have a focus on the concept of ‘curtilage’, and I get the impression that there may be a degree of confusion over this, and in particular that some of the thinking might be unintentionally conflating more than one issue.

By far the best coverage of these subjects is in chapter 2.2 of Martin Goodall’s book The Essential Guide to the Use of Land and Buildings under the Planning Acts (2017, 2019), and I would strongly suggest reading that.

(a) The extent of the curtilage of a building (listed or unlisted)

The first issue appears to be the extent of the curtilage (if any) of a building. This is not a listed building issue: it of course does not depend on the building being listed – unlisted and listed buildings have a curtilage (or not) in the same way.

The extent of curtilage can have planning relevance, for example because some permitted development (PD) is available only ‘within the curtilage of a dwelling’.

In principle there could therefore be value in defining the curtilage of a building within a digital planning system, for example to give greater certainty on the application of PD.

The objection to that would be that curtilage is (to quote some of the case law/commentary) ‘complicated, ‘a term of art’, etc etc, requiring individual detailed expert assessment in each case. The curtilage of a building is essentially (there is a great volume of case law on this) an area of land (if any) ‘so intimately associated’ that it forms ‘part and parcel’ of the building to which it is related, serving that building in ‘some useful but nevertheless subservient way’, not too distant from it, and not separated from it by land in another use. Curtilage can change over time (for example if you bought part of next door’s garden and used it as a garden, it would then become part of the curtilage of your dwelling).

That makes curtilage sound complex and unclear, and it certainly can be, and seeking to define the curtilage of every building would be an absurdly unrealistic task in the real world. However, a counter-argument could be that in maybe 60+% of cases the answer is clear (for most urban or suburban dwellings, the curtilage will be the garden or yard, and it’s obvious where the garden/yard begins and ends); and that defining curtilage in that say 60% of cases (if that could be achieved in a proportionate way) would thus help in that 60% of cases, even if it remained undefined in other cases. If that were done, a straightforward mechanism would be needed to deal with any false positives/false negatives in the 60% of cases.

(b) What is covered by the listing of a listed building

I’m not 100% clear whether this is a point at issue in this project, but it may be. It is a separate question. The first point is that obviously only structures can be covered by listing, not land, so you can’t draw a red line around land and say that that landholding is listed or covered by listing. The second is that although the ‘curtilage’ of the building may be relevant, it is largely a red herring in this context, because as below it is only one of the factors involved (and in practice seldom the decisive issue).

The legal position on the extent of listing is now well-settled in case law, nothing much has changed for 15+ years, and recent case law (eg Blackbushe Airport in the Court of Appeal) has cemented this.

Essentially, firstly, a structure physically attached to a listed building will normally be covered by its listing if, at the date of listing, it was in the same ownership as the listed building, and was ancillary to it.

Secondly, a structure not attached to a listed building will be covered by its listing only if it is pre-1948, and, at the date of listing (or, probably, at 1969 if later), was in the same ownership as the listed building, and ancillary to the listed building, and in the curtilage of the listed building. These are essentially issues of fact (for example there is currently no requirement for ‘heritage experts’ to decide whether the structure in question has any heritage value, because that is – arguably bizarrely! – entirely irrelevant; many structures which under the statute are covered by listing have no, or negative, heritage significance).

Again, it might be helpful if a digital planning system could know whether a structure is covered by listing or not. However – given that virtually none of the building date/past ownership/use factors involved (as above) are likely to be accessible in databases – it is extremely hard to imagine how that could be achieved, even for just a part of the listed building stock!

Happy to enlarge on this if that’s useful.

[kieranwint]

Hi @Jonathan-Thom,

Thank you for your comments, very insightful!

I think we broadly agree on everything mentioned here. As we understand it, the curtilage is what is needed to make planning decisions. It's not the land that's listed, but the land is encapsulated and will be used as an indicative marker that there may be a listed building and a notifier to check with the respective local authority.

Because of the difficulty in there being no concrete definition of curtilage, we are working with HMLR to align our specifications as best as we can, for 2 reasons:

• So that we can have consistent geometries for listed building 'curtilage'
• We reduce the burden on LPAs, who would otherwise need to create separate datasets for a similar but complex subject to say the least!

It's also important to note at this time that although we appreciate an accurate curtilage dataset is near impossible, this would still be the aspiration for the platform. The reason for our keen nature on getting this sorted with HMLR's Local Land Charge (LLC) alignment is because we've always maintained that some data is better than no data.

I'll use the email you've added above to get you invited to the working group tomorrow, it's at 11:00, hope to see you there.

Thanks again!

[MrMikeRose]

Further to my previous update in this discussion this is an update to our approach to the listed building specification and the 'curtilage issue'

Firstly, thank you to @Jonathan-Thom ^ I think he has captured far more thoroughly than I ever could where we have got to in terms of our learning!

We agreed at the last working group that we consider how we use the Historic England data and the data required by HMLR for Local Land Charge (LLC) Register alongside the planning data specification we have been working on.

Further we agreed that the curtilage requirement of HMLR schema would be a sufficient PROXY for the detailed curtilage envisaged in planning with appropriate caveats on considering the data indicative and not definitive.

What we have been doing since that last meeting is:

Evaluating the HMLR listed building LLC schema against the MHCLG listed building specification.

We have mapped these and identified where there are common aspects across the schemas*, where possible we have aligned the MHCLG specification to the HMLR schema.

Evaluating data currently provided to LLC schema

We have been looking at the data that has been provided by some local authorities to HMLR as part of the alignment activity

Engaging with HMLR

We have been discussing our preferred approach and developing a position across both HMLR and MHCLG.

Amending our pilot specification

In light of feedback and the alignment activity we have made some minor tweaks to the MHCLG specification.

Producing a 'composite schema'

Recognising that there are 2 asks on LPAs for slightly different data we have begun developing a composite schema, based on our alignment work, which when viewed from an LPA perspective outlines the whole ask with regard listed building data.

Producing a data flow diagram

Building on the above work we have produced an expected data flow to help visualise how we expect "things" to fit together.

Working with HMLR to engage with Local Authorities

As a result of this work we preparing for jointly hosting sessions at HMLR roadshows with Local Authorities on 7, 26 and 28 November where we will be sharing this work and discussing further.

Next Steps

Updating the working group

Tomorrow!

Attending the HMLR roadshows

Exactly that ^.

Engaging with Historic England

As the holder of the statutory register of listed buildings we are continuing to engage with Historic England so they are aware of our work, the overall data requirements and can input to overall processes where appropriate.

Updating all of our documentation

We need to update all the documentation to capture the position now, this includes the specification itself and the associated guidance. It is our aspiration to work with HMLR to produce a consolidated set of guidance for LPAs (to mirror the 'composite specification').

Producing and applying caveats to the listed building data

We will continue to work with internal colleagues in MHCLG to ensure the wording used to explain the listed building data satisfies the requirements that it is used as an indication of a listed building.

Further internal MHCLG discussions relating to mandating the MHCLG specification

There is a power in the Levelling Up and Regeneration Act 2023 (LURA) which enables MHCLG to mandate a data specification as an 'approved data standard" which then becomes a statutory requirement to comply with. We will continue to work with policy colleagues to identify if we need to proceed to mandating at this time.

Please feel free to engage with us via this discussion if you want to find out more about ^.

*using this terminology when describing both the HMLR schema and MHCLG specification together

[Jonathan-Thom]

Hi kieranwint

[Have only just seen MrMikeRose’s
post so not taken into account below!]

Many thanks for this response. As my first post said, effective digital planning is fundamental to the future of the planning system (given the impossibility of resourcing the current system, it won't work without it!), so I’m keen to help. (Of course the word ‘effective’ is vital here, and presumably the various MHCLG projects in this area are working to ensure that it is, so again I’m keen to help!)

I will add a bit more detail to my previous post because it looks as if it might be useful to you.

(a) Curtilage of buildings

Firstly I'd suggest that this should be a wider project, not a listed building project – obviously most buildings with curtilages won't be listed, and there’s no difference between the two, so no reason to tackle listed buildings separately.

Defining the curtilage of a building (listed or not) is likely to be useful in a digital planning system, eg for PD purposes. But presumably the project can’t step outside the confines of the law.

As I suggested, although the legal definition of curtilage is in that unhelpful ‘circumstances of each case’ zone, a priori I suspect that you could get quite a long way using the 80:20 principle – in urban areas, armed with an OS plan showing title boundaries, and leaving out properties where there seems to be room for doubt, you or I (or AI !) could probably get to a say 60-70% coverage at least of residential houses/gardens without too many errors. If you tried to get to 80+% coverage the error level would increase markedly; and in rural areas I would not suggest this as a worthwhile exercise at all, or certainly not initially. But of course even in straightforward cases there will always be at least some errors in any such exercise, so you would need a protocol which explains to all users at both an overall and site level what has been done and how, and that it is a desktop exercise which inevitably will include false positives/negatives, and the straightforward and presumption-free mechanisms which would need to be in place for dealing with these.

Are you thinking on these lines, or if not how do you see this working?

(b) Listed buildings

Your post suggests that the project does also encompass what is covered by the listing of a listed building, which is a different, and in definition/mapping terms much more difficult and complex question.

Even if you had mapped curtilage (and a lot of listed building curtilages would fall into the ‘too difficult’ category above), that in no way provides a reliable indication of the extent of listing, because too many other factors are involved.

In particular, the Court of Appeal in Blackbushe Airport (2021) reconfirmed previous case law, ie that “…in order to be treated as if it were part of the listed building, a freestanding structure within the curtilage must also be ancillary to that building” [paragraph 110]. Blackbushe Airport Ltd v Hampshire County Council, R (On the Application of) & Ors [2021] EWCA Civ 398 (18 March 2021). That point is now so well established in case law that in 2023 it was incorporated into the new statute in Wales, which expressly requires structures to be ancillary to the listed building at the date of listing (as well as being post-1948 etc – see s76 (5) Historic Environment (Wales) Act 2023.

(That same paragraph 110 in Blackbushe Airport incidentally also reconfirms that listed buildings and unlisted buildings have a curtilage in the same way, as above).

I’m happy to be further involved in these questions (there’s also the question of mapping the actual listed building!).

Also happy to be involved on other wider heritage questions, which could have real benefits and on which it may be much easier to make real progress!

[MrMikeRose]

@Jonathan-Thom thanks so much for your interest and input, it is really helpful.

The HM Land Registry approach is pretty much exactly what you describe in (a). For the purposes of conveyancing they are interested in the title boundary (which is what they define as curtilage in their guidance), we understand the differences with planning curtilage which you outline and the likely expense to create a definitive 'planning curtilage' (acknowledging your point about ALL buildings having a curtilage).

Because of that expense, and the need to have something for planning, our approach is basically what you describe in (a) - we will use the 'title boundary' requirement of the Local Land Charge Register (operated by the HMLR) and explain that the data is indicative and further work by a user would be needed to understand the curtilage for planning decision making.

Acknowledging also your point under (b) and the further vagueness of concepts such as 'the setting' in planning we believe that our proposed approach is the most pragmatic way to get useful data into the digital planning process quickly whilst retaining (as Kieran says) that at some point it would be ideal to have definitive data for listed building curtilages (when considering just this data).

To be clear, we know this is not the perfect solution and for that reason the decision was arrived at in consultation with the LPAs on the working group (it was the primary reason for the working group) to ensure any approach had their backing - given the complexity you outline!

More than happy to continue this discussion!

[Jonathan-Thom]

Thanks. Unfortunately I can't make this morning's meeting (other things have come up), but I will comment further when I get a chance!

[Jonathan-Thom]

As promised, a further post – thanks for this further information, though obviously, having had no involvement in the project outside these posts, I’m still a bit unclear about detail, and indeed about the project as a whole!

In particular there is no such thing as a ‘planning curtilage’ (or ‘listed building curtilage’): it’s just curtilage, defined in decades of case law. If I’m understanding the post correctly (which I may not be!), HMLR has decided to make an assumption that curtilage boundaries and ownership boundaries are the same thing. If so, that obviously would not be correct in law, but more importantly would be incorrect in practice in very many cases – it would give incorrect curtilage boundaries for many millions of buildings. That would not be a minor problem which could be picked up later, but a major issue which would need careful handling in the project architecture from the beginning.

However I could probably comment in a much more positive way (!) if I knew a bit more about the project – I’d be happy to do a Zoom etc call with you/some of the project team if that would be helpful – please let me know. jonathan.thompson@cla.org.uk

[kieranwint]

Hi @Jonathan-Thom, I can only apologise for the wait on this response.
It would be brilliant if we could have a conversation on this, so I'll drop you an email and hopefully we can sort a time in due course.
Thanks for your continued participation!

[Jonathan-Thom]

Many thanks - very happy to meet and to help with this project. There is a concern about the wider project, potentially on detail, but also on consultation - it's of course very important to be consulting LPAs, but of course they are numerically only a small proportion of users of the planning system/finished software, and not consulting others (if that's correct!) is potentially an issue in democracy/transparency terms, but more importantly must threaten the overall outcome - IT projects are notoriously prone to failure of course, and not consulting the majority of end-users (in this case applicants, their planning and other consultants, other stakeholders) may not maximise the probability of success. We are intending to raise this in our normal contacts with MHCLG ministers and civil servants, but it would be helpful to have a conversation ahead of that! Best wishes Jonathan Jonathan Thompson MA MBA DipM Senior heritage adviser Country Land and Business Association (CLA) t: 020 7235 0511 | m: 07525 196835 e: ***@***.******@***.***> | w: www.cla.org.uk<http://www.cla.org.uk/> 16 Belgrave Square, London SW1X 8PQ The Advisory Services are made available to members on the basis that a member’s rights to compensation and the liability (if any) of CLA and its officers and/or its staff advisers, are restricted in the following ways. In the event of any advice given by any CLA staff adviser being given negligently or otherwise being incorrect no liability whatsoever is accepted by CLA or its officers or by its staff advisers concerned (a) towards any person who is not the current CLA member to whom the advice was directly given, (b) to any person in respect of consequential loss or loss of profits, or (c) to any person for any sum exceeding £50,000 in respect of any one enquiry (whether made or responded to orally or in writing and whether dealt with at one time or over a period of time). Any person making use of the Advisory Services accepts such restrictions. If damages restricted to the above financial limits would be inadequate in the circumstances members should consider referring to appropriate professional advisers in private practice before taking any particular course of action potentially or actually involving any substantial amounts of money. Solicitors in the CLA Legal Department are not covered by the Solicitors’ Indemnity Fund in relation to professional negligence in relation to any advice given by them. No responsibility for loss occasioned to any person acting or refraining from action in reliance on or as a result of the material included in or omitted from this message can be or is accepted by the author(s), the CLA or its officers or trustees or employees or any other persons. © Country Land and Business Association Limited. All rights reserved. No part of this publication may be reproduced or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, or stored in any retrieval system of any nature without prior written permission of the copyright holder except as expressly permitted by law. Country Land & Business Association Limited. Registered in England and Wales: 6131587. Registered Office: 16 Belgrave Square, London, SW1X 8PQ.

…

________________________________ From: Kieran Wint ***@***.***> Sent: Friday, November 22, 2024 2:32 PM To: digital-land/data-standards-backlog ***@***.***> Cc: Jonathan Thompson ***@***.***>; Mention ***@***.***> Subject: Re: [digital-land/data-standards-backlog] Listed buildings (Discussion #44) Hi @Jonathan-Thom<https://github.com/Jonathan-Thom>, I can only apologise for the wait on this response. It would be brilliant if we could have a conversation on this, so I'll drop you an email and hopefully we can sort a time in due course. Thanks for your continued participation! — Reply to this email directly, view it on GitHub<#44 (reply in thread)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/BMHLIKTMPEW2LHIUPLVBWTD2B46BFAVCNFSM6AAAAAA7M2SWLWVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTCMZUHE4DENI>. You are receiving this because you were mentioned.

[colmjude]

Schema changes

We have tidied up the schemas for the 2 datasets related to listed buildings.

listed-building

Firstly, there is the listed-building dataset, which we get from Historic England. Originally, we have 2 fields (reference and listed-building) both populated with the same data - the official listed building number assigned by Historic England. Therefore we have removed the listed-building field. (see commit digital-land/specification@8a4d4f5)

listed-building-outline

In the listed-building-outline dataset we had a listed-building-grade field. This is not needed. The grade is provided as part of the listed building record so it does not need to be repeated on the listed building outline record. Having 2 fields for the same data point can lead to discrepancies in the data. We want to avoid this where possible.
Therefore, we have removed thelisted-building-grade field (see commit digital-land/specification@a0fd212). Specification is now at version 1.2.0

[colmjude]

Potential changes to listed building outline schema

We are reviewing 2 proposed changes to the listed building outline specification.

1. remove documentation-url

At the moment, we ask for a documentation-url. Most data providers have submitted data with this field filled in with a link to the listed building page on Historic England's site. That link is already provided in the official listed-building record. Therfore, we don't need to repeat it in this dataset.
However, before we remove it we wanted to check whether there is an official document that contains a red-line boundary (or equivalent) drawing of the listed building outline. If that is something that exists it would be better to collect a link to that rather than duplicating the link to the Historic England listing.
If that doesn't exist we will consider removing the field.

2. add a uprn field

Do listings have an associated UPRN?
If they do and it's possible to retrieve that data a uprn field could be a good addition to the listed-building-outline dataset. Including UPRNs help to link relevant datasets together, improving the accessibility and usability of property/building-related data.

An alternative to adding a uprn field to listed-building-outline would be to augment the listed-building dataset with a uprn field. It is not data we expect to get from Historic England as part of the official dataset but if we can get it from somewhere else it might make more sense to added to those records.

This is something we need to work through.

[colmjude]

We checked with HMLR and they confirmed they do not currently receive any URLs to relevant documents about the listed building, other than the link to the official listing on Historic England's site.

Therefore, we have removed documentation-url from the listed-building-outline dataset.

If we verify needs that can be satisfied by capturing supporting documents as data then we can consider re-introducing it.

---

Specification version 1.3.0

[kieranwint]

Proposed name change

Furthermore to the proposed (and made) changes to the listed building specification above, and taking into consideration all that we have learned about listed buildings (including curtilage and the difficulty this poses) as well as how our specification has changed over this process, we need to re-assess the name of the dataset, as "listed-building-outline" is no longer fit for purpose.

Working with our team of planning experts alongside our content designer, we’re proposing that "listed-building-related-area" is a name that more accurately describes this dataset. We’d love your feedback on this, please feel free to get involved and comment your views here.

[PRWhitehouse]

The majority of local authorities will have captured all listed buildings as a polygon, or line, or point already during their GIS developments for planning and LLC / CON29 reports. There were available through INSPIRE. Note: Listed Buildings are not just the buildings, there contain walls, gateways, fountains, ice houses, even internal decorations. The description holds the key (e.g. wall 200 feet south from main gateway) maybe AI can interpret this information.

[kieranwint]

Thanks for this, and completely understand that the listing is not always a building as such which adds a layer of complexity when it comes to curtilage for sure! Interesting point you make on possibly utilising AI to interpret this information. That's not something on our radar right now but perhaps could be one for the future...!

[kieranwint]

MHCLG and HMLR joint specification

Over the past few months, we have been working closely with the Local Land Charge programme at HMLR to try and reduce the burden on local authorities providing listed building data, as we are both asking for similar data.

As a result of this work, we have aligned our data asks. To do this we have mapped the fields we ask for in our specification with those that also appear in the local land charge schema.

Where there was not a suitable mapping, we have retained what is required to satisfy the planning data need.

We are currently working on updating our specification and guidance which is the first step to everything aligning.

Then we will look to produce consolidated guidance with HMLR to clearly explain the approach for a local authority user.

Joint specification

field-name	Programme requirement	Comments
registration-date	HMLR requirement
originating-authority	This field satisfies both HMLR and MHCLG requirements	This maps to organisation in the MHCLG specification
further-information-location	HMLR requirement
ID	HMLR requirement	Note: This is geometry identifier
land-interest-geometry	This field satisfies both HMLR and MHCLG requirements	This maps to geometry in the MHCLG specification
land-description	This field will satisfy both HMLR and MHCLG requirements (if added to MHCLG spec)	As a result of our work with HMLR, we are looking to add a description field to the MHCLG specification, in which case these two map to one another
land-description: charge-address	HMLR requirement
land-description: charge-address Line 1	HMLR requirement
land-description: charge-address Line 2	HMLR requirement
land-description: charge-address Line 3	HMLR requirement
land-description: charge-address Line 4	HMLR requirement
land-description: charge-address Line 5	HMLR requirement
land-description: charge-address Line 6	HMLR requirement
land-description: postcode	HMLR requirement
uprn	This field will satisfy both HMLR and MHCLG requirements (if added to MHCLG spec)	We may add a uprn field to the MHCLG spec once we have completed an analysis of local land charge data
land-description: charge-geographic-description	HMLR requirement
old-register-part	HMLR requirement
originating-authority-charge-identifier	HMLR requirement
statutory-provision	HMLR requirement
further-information-reference	This field satisfies both HMLR and MHCLG requirements	This maps to reference in the MHCLG specification This field is referred to as "LA File reference" in the local land charge schema
charge-creation-date	This field will satisfy both HMLR and MHCLG requirements	This maps to start-date in the MHCLG specification, and is the date from which the building was listed
supplementary-information	This field satisfies both HMLR and MHCLG requirements	This maps to notes in the MHCLG specification
listed-building	MHCLG requirement	This ask has not changed and is required to link to provided geometry with the original Historic England listing
name	MHCLG requirement	The name of the listed building
entry-date	MHCLG requirement	The date the information was entered as a record
end-date	MHCLG requirement	The date the record of the validity ends

[kieranwint]

Joint specification update

We have recently completed an analysis of some Local Land Charge data currently held for Listed Buildings in order to assess whether the joint specification’s first iteration (see above) contains a suitable alignment of fields between the HMLR schema and MHCLG specification. As a result of this analysis, we are looking at making the following amendments to both the joint specification and the MHCLG specification.

• We will remove the alignment of organisation from originating authority - We use a reference code for the organisation field, and the data we have analysed contains a string in the LLC originating-authority field. Inference may be possible, but could become inconsistent, so we have decided to keep them separate.
• We will remove the alignment of start-date from charge-creation-date - The analysis we completed showed differences between dates for which we currently hold data for on planning.data with those held in the LLC data. As there was a wide variance across the analysed entities, we will look to keep them separate.
• We will add uprns to the MHCLG specification - Although no uprns were available in the data we analysed, this does not reduce the value the addition of uprn data can bring. We are deciding to add this as uprns (plural), so if a listing has multiple then these can be provided. This will be aligned with the uprn field which is in the LLC schema.
• We will add description to the MHCLG specification - In the data we analysed, there was data in the charge-geographic-description fields which could be valuable, so we will add this field to the MHCLG specification and align it with charge-geographic description from the LLC schema.

What this does to the joint specification is as follows:

field-name	Programme requirement	Comments
registration-date	HMLR requirement
originating-authority	HMLR requirement
further-information-location	HMLR requirement
ID	HMLR requirement	Note: This is geometry identifier
land-interest-geometry	This field satisfies both HMLR and MHCLG requirements	This maps to geometry in the MHCLG specification
land-description	HMLR requirement
land-description: charge-address	HMLR requirement
land-description: charge-address Line 1	HMLR requirement
land-description: charge-address Line 2	HMLR requirement
land-description: charge-address Line 3	HMLR requirement
land-description: charge-address Line 4	HMLR requirement
land-description: charge-address Line 5	HMLR requirement
land-description: charge-address Line 6	HMLR requirement
land-description: postcode	HMLR requirement
uprn	This field will satisfy both HMLR and MHCLG requirements	This maps to uprns in the MHCLG specification
land-description: charge-geographic-description	This field satisfies both HMLR and MHCLG requirements	This maps to description in the MHCLG specification
old-register-part	HMLR requirement
originating-authority-charge-identifier	HMLR requirement
statutory-provision	HMLR requirement
further-information-reference	This field satisfies both HMLR and MHCLG requirements	This maps to reference in the MHCLG specification This field is referred to as "LA File reference" in the local land charge schema
charge-creation-date	HMLR requirement
supplementary-information	This field satisfies both HMLR and MHCLG requirements	This maps to notes in the MHCLG specification
listed-building	MHCLG requirement	This ask has not changed and is required to link to provided geometry with the original Historic England listing
name	MHCLG requirement	The name of the listed building
organisation	MHCLG requirement	The organisation responsible for the listed building, provided with a specific reference
entry-date	MHCLG requirement	The date the information was entered as a record
start-date	MHCLG requirement	The date on which the building was listed
end-date	MHCLG requirement	The date the record of the validity ends

The changes to the MHCLG specification and guidance will be looked at in the coming weeks.

[psd]

Listed Building Outline

A note on "what is a listed building outline".

We began our work on listed buildings by being deliberately imprecise about the geographic area to be provided for a listed-building-boundary beyond it being

an area to be considered by tools such as PlanX to inform if a planning application is affected by a Historic England listing

Since then, the team have been working with LPAs funded to provide data for PlanX through the Open Digital Planning community, HM Land Registry, Historic England and others to better understand the information LPAs currently hold, as well as the needs of users of this data such as PlanX.

We have learned that there is currently a lot of variance in how this data is currently held and used within an LPA:

• Most LPAs only consider the point data from Historic England when applications are processed, rather than creating listed building outlines up-front.
• Some LPAs just record the outline of the listing, eg just the protected shop front.
• Some LPAs use the building outline from OS master map, which has restrictions on licensing.
• Many LPAs use the Land Registry title boundary (index polygon), released under the OGL3 licence.
• some have created specific "curtilage" boundaries following previous Historic England guidance on Listed Buildings and curtilage.
• an increasing number of LPAs now follow guidance from the HMLR as they join the Local Land Charges programme

Our conclusion is that the boundary to be provided as the listed-building-outline SHOULD be the same boundary an LPA needs to record for Local Land Charges purposes as defined by the guidance from the HMLR.

Users of the listed-building-outline data may then choose to buffer (widen) these boundaries, or consider a smaller area, such as the outlines of buildings, or parts of the building within the boundary, depending on their use-case.