Appeal 6001224

The appeal is dismissed.

The site visit was undertaken by a representative of the Inspector whose recommendation is set out below and to which the Inspector has had regard before deciding the appeal.

The application form seeks outline planning permission with the matters of access, layout and scale sought for approval. Therefore, the matters of appearance and landscaping are reserved for subsequent approval, and I have considered the proposed elevation drawings provided on the basis that they are indicative only.

With regards to the matter of layout, the ‘Site Layout Plan’ ([name] 001 Rev.0) before me is annotated ‘Existing building’. This corresponds with the position of the building indicated on the ‘Location Plan’ ([name] 002 Rev.0) and both drawings have the project title ‘Resue (sic) of existing building on land at Millfield, Cambridge’. These are the only layout drawings referred to on the Council’s decision notice and no further site layout drawings specifically indicating the position of the proposed development have been submitted with the appeal. I return to this matter under other considerations.

Schedule 7A of the Town and Country Planning Act 1990 (as amended) introduced a statutory framework for [name] (BNG), and it applies to all planning applications made on or after 12 February 2024. As such, unless exempt, development proposals are usually subject to the mandatory requirement to deliver a BNG of at least 10%. The application form indicates that the scheme would be exempt from BNG requirements on the basis that it is a self‐build/custom‐build project. This matter is considered under the second main issue.

The main issues are whether or not the proposed development would be: • in an acceptable location in terms of flood risk; and • subject to biodiversity net gain (BNG) requirements.

The appeal site sits within [name] 2 and 3. Accordingly, in line with the ‘Planning and flood risk’ chapter of the National Planning Policy Framework (the Framework), the proposal for a new dwelling requires a sequential risk-based approach to be undertaken except where a site-specific flood risk assessment demonstrates that no built development within the site boundary, including access or escape routes would be located on an area that would be at risk of flooding from any source, now or in the future.

The appellant’s statement of case includes a sequential test. The Council acknowledges that the Planning Practice Guidance (PPG) advises that for a single dwelling it would not usually be appropriate to extend the search area beyond the specific area of a town or city in which the proposal is located, or beyond an individual village and its immediate neighbouring settlements. Whilst the search area applied is ‘the administrative boundary of South Cambridgeshire District Council’, and the selection filters suggest sites with ‘realistic potential’ will be considered, the sites discounted relate to 10 ‘single self-build’ plots with outline or full planning permission.

The PPG does not limit the sequential test to previously approved sites. The Council contends that there are areas within Willingham and surrounding areas within [name] 1. This has not been disputed by the appellant nor is there information before me to demonstrate why the suggested areas within [name] 1 do not provide realistic potential for a single dwelling. Therefore, there is no compelling evidence to suggest that the development of a single dwelling could not be directed to areas at lower risk of flooding.

Furthermore, no detailed information has been provided to show how the plot value threshold of £160,000 was reached. This further undermines the criteria applied particularly given that there is no suitable mechanism before me to restrict the dwelling to a ‘low cost’ self-build/custom-build dwelling, a matter which I consider further under the second main issue. Overall, the deficiencies identified indicate that the sequential test for a new build dwelling on the appeal site is not passed.

The appellant’s site-specific Flood Risk Assessment is dated 2023. The Council’s officer report suggests that it does not take into account more recent flood modelling. Furthermore, in terms of the Flood Evacuation Plan (FEP) provided with the appeal, it relates to a ‘change of use of an existing building’ rather than the new build proposed. In any case, I share the Council’s concerns that no details have been provided in terms of potential water depths relative to the evacuation routes during a flood event. In addition, it is not clear whether any alterations to the access routes would be required to make them safe and accessible in a flood event. The FEP also contradicts the proposed floor plans as it suggests ‘no sleeping accommodation at ground floor’, yet the drawings indicate a bedroom at ground floor level. In the circumstances, this is not an instance where a site-specific flood risk assessment has demonstrated that the development would not be at risk of flooding, and so the necessity for a robust sequential test cannot be set aside.

Accordingly, the proposed development would not be in an acceptable location in terms of flood risk. In that regard, it conflicts with [name]/7 and CC/9 of the Cambridgeshire Local Plan (2018) (LP) which require developments in line with the development frameworks which includes consistency with other policies in the LP, most particularly in this case that being that in order to minimise flood risk, development will only be permitted where the sequential and exception tests established by the Framework demonstrate the development is acceptable. For the reasons set out, the proposed development is also contrary to the ‘Planning and [name] section of the Framework.

The Council has suggested a condition to secure the scheme as a self-build or custom-build dwelling. However, there are numerous enforceability issues with the condition as proposed. Firstly, in relation to knowing for certain that the person building the house will live in it, meaning enforcement action is unlikely to be possible until the house is completely built and occupied. Secondly, if the Council considered that the first occupier had not had primary input into the design and sought enforcement, compliance would require a subsequent owner to persuade the original builder to return and live in the property. It would be impractical and unreasonable to require this. Therefore, the suggested condition would not meet the tests of the Framework.

A planning obligation would be the most appropriate mechanism to secure the proposed dwelling with certainty and precision as a dwelling designed and occupied in line with the definitions in the Self-Build and Custom Housebuilding Act

In the absence of an appropriate mechanism, there is the potential that the proposed development would be an open market dwelling. In these circumstances, the development would not be exempt from the mandatory BNG requirements.

I have considered the imposition of a suitably worded planning condition to address BNG. However, I have not been provided with suitably detailed evidence to know what the current baseline of the site is for the purposes of establishing a metric. As a result, I am unable to understand what a gain would equate to in either quantitative or qualitative terms. Furthermore, and adopting the precautionary principle, I could not recommend granting a planning permission for works which may, in so implementing them, affect a site to which prior assessment needs to be undertaken as to its value and/or condition in biodiversity terms. With this and the above in mind, the proposed development would be liable to provide BNG under the statutory duty.

Consequently, the proposal would be subject to BNG requirements, and no information has been provided to suggest that this would be adequately met. In that regard, the proposal is contrary to LP policy NH/4 and the [name] (2022) which sets out that new development must aim to maintain, enhance, restore or add to biodiversity.

Notwithstanding my conclusion under the first main issue, there appears to be an existing prior approval for a barn conversion to a dwelling on the appeal site1. The Council suggests the current state of the barn means that it does not consider that the prior approval could be implemented. However, the Council has not quantified in any detail why it would not be lawfully implementable. In the circumstances I can only conclude that, in the event that the appeal was dismissed, there would be a realistic prospect that the appellant could and would implement the conversion.

Whilst the conversion has to stay where it is, and a new build dwelling could go elsewhere; the appellant suggests that the proposed development would reuse the same footprint as the existing building. Given the matter of layout is not reserved, it would have been preferable to have a proposed layout plan specifically relating to the proposed development. However, given the clear intention of the appellant, this may have been resolved through a condition requiring the existing building to be first removed with the proposed dwelling being put in its place. Putting one in place of the other means that theoretically speaking there would be no increased risk in flood risk terms. This includes in terms of access and egress from a dwelling on the site which would be similar in either instance.

A new build dwelling would offer the potential to build in flood resilience measures, including in terms of finished floor levels. Had the recommendation been to allow the appeal, the discrepancy between the FEP and floor plans could also have been resolved through the submission of amended floor plans to show no sleeping accommodation at ground floor. However, given that such an amendment would not overcome the wider uncertainty regarding the scheme’s compliance with [name] requirements, no revised plans have been sought.

I have found that the proposed development would not be in an acceptable location in terms of flood risk. In that regard, the existing approval for the conversion of a barn on the site to a dwelling is a fallback consideration of considerable weight and which would outweigh the harm identified under the first main issue as the risk would be comparable in either instance.

However, as there is no suitable mechanism to secure the proposed development as a self-build/custom-build dwelling, it does not benefit from a BNG exemption. For the reasons set out, this cannot be resolved by condition. This is a matter of overriding concern and in the circumstances, I can only recommend that the appeal should be dismissed.

I have considered all the submitted evidence and my representative’s report and on that basis the appeal is dismissed.