In Hill v London Borough of Bromley, an inspector dismissed the landowners’ appeal after the local planning authority had refused to grant an application for a lawful development certificate (‘LDC’) (decision letter issued 19 March 2019). That decision was subsequently overturned by the Planning Court, and the appeal sent back for a re-determination.

The LDC appeal concerned an important point of legal principle over the lawful status of a semi-finished residential development which had been built pursuant to a grant of prior approval. The case will be of particular interest to any developer intending to convert a building into multiple units under ‘change of use’ permitted development rights.


In December 2013, the landowners acquired prior approval to exercise permitted development rights to convert an office building to residential use (under the former Class J of the 2013 GPDO). The landowners had every intention of progressing the development as quickly as possible, and in enabling the eight flats to be occupied for rent.

What happened next is covered in a previous article: see Hill v London Borough of Bromley: Round 1 – When does an unauthorised change of use gain immunity from enforcement?

Essentially, the council raised doubts over whether the building had been lawfully used as an office, and hence, there was a question mark whether the permitted development rights could be exercised. In July 2017, this dispute was eventually resolved in the landowners’ favour, after a public inquiry; however, completion of the development was seriously delayed as a result.

By the end of May 2016 just one flat had been finally fitted out, and was occupied, whilst basic services had also been laid to the shell of the former office building. By December 2016, works to the other seven flats had progressed to various stages of completion, but none of them was finally fitted out or occupied. Some of the flats just lacked bathrooms, whereas others had no fixtures or fittings at all.

A legal wrangle then ensued over whether the development work which had been carried out was enough to keep the benefit of the permitted development rights alive. That question was also complicated by legislative changes made to the GPDO since the time the prior approval had been obtained. On 15 April 2015, the 2013 GPDO was consolidated and replaced by the 2015 GPDO, with Class J becoming Class O. The 2015 Order was then subsequently amended on 6 April 2016, introducing a new time limit condition.

All this meant that one of two different legal requirements might potentially apply:

  • Either, the use of the building within Class C3 (‘dwellinghouses’) of the Town and Country (Use Classes) Order 1987 (‘the UCO’) had to be begun before 30 May 2016 under limitation J.1(c) of the 2013 GPDO; or
  • The permitted development under Class O had to be completed within three years of the prior approval date (i.e. by December 2016) by reference to condition O.2(2) of the amended 2015 GPDO.

The landowners applied for an LDC to confirm that the eight flats were lawful, but the council refused, and an appeal followed.

What did the inspector decide?

At the initial public inquiry the planning authority successfully argued that seven of the eight flats had not been completed by the December 2016 cut-off date, having regard to condition O.2(2) of the 2015 GPDO. The inspector agreed with the council that these matters were to be decided with reference to the court’s decision in Gravesham, and the fact that each flat formed its own separate planning unit.

Gravesham is commonly cited as the defining legal test of what constitutes a ‘dwellinghouse’, but the landowners had disputed its relevance to the appeal. They argued that the guiding test was set down by the court decisions in Welwyn Hatfield and Impey instead. These rulings confirmed that a residential change of use might occur prior to ‘physical’ completion in the sense normally contemplated by Gravesham – and also, that actual, intended or attempted use of the building (as a dwellinghouse) were equally relevant considerations which the council had totally ignored. These matters had to be considered “in the round”.

The landowners subsequently took their fight to the Planning Court on three separate grounds and won.

What did the court decide?

The Secretary of State and the council conceded the landowners’ claim, by consent order, and without a hearing, on the following ground:

The Inspector regarded Gravesham BC v. SSE [1984] P&CR 142 as superseding Impey v SSE (1984) 47 P&CR 157 (as approved in Welwyn Hatfield BC v SSCLG [2011] UKSC 15) as to the definition of a dwellinghouse, such that the question he asked himself was ‘Does the building in question (or part thereof) meet the definition of a dwellinghouse, i.e. does it have the distinctive characteristic of the ability to afford to those who used it the facilities required for day to day private domestic existence?’ The Inspector should have given regard to the test in Welwyn/Impey as to when a material change of use can have occurred in the process of conversion to a residential use, as well as considering what that residential use was, and the Inspector did not directly do so. The answer he would have come to may well have been the same if he did, but in failing to consider the test in Welwyn/Impey and preferring to apply Gravesham instead he may have fallen into error on the correct lawful test to apply.


The landowners subsequently won their case at the subsequent re-determination hearing, following the court quashing. For an exploration of those issues, please see article Hill v London Borough of Bromley: Round 3 When is permitted development completed?

Ben Garbett advised the successful landowners, Mssrs Hill, throughout the course of their dispute. If you would like to discuss any of the issues raised in this article, please contact Ben.

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This article is for general information purposes only and does not constitute legal or professional advice. It should not be used as a substitute for legal advice relating to your particular circumstances. Please note that the law may have changed since the date of this article.