The Supreme Court handed down a further judgment in the case of Secretary of State for Communities and Local Government and Another v Welwyn Hatfield Borough Council [2011] UKSC 15 on 6 April 2011 concerning the application of planning law to a dwelling house disguised as a hay barn.

The first issue was whether there had been a relevant change of use of the building within the provisions of the Town and Country Planning Act 1990 (“the Act”) which impose a time limit for taking enforcement action against breaches of planning control. The second issue is whether the owner’s deceit should preclude him from benefitting from those provisions.

During 2001, Mr Beesley, the second respondent, applied for and obtained planning permission to construct a hay barn for grazing and haymaking on open land which he owned in the Green Belt. Between January and July 2002 he constructed a building which was to all external appearances the permitted barn, but internally was a dwelling house with full facilities, including garage, lounge, living room, toilet, etc. In August 2002 he and his wife moved in and lived there continuously for four years. Welywn Hatfield Borough Council, the appellant, in whose area the property lies, remained unaware throughout that the building was or was being used as a dwelling house.

Section 171B(2) of the Act provides that “where there has been a breach of planning control consisting in the change of use of any building to use as a single dwelling house, no enforcement action may be taken after the end of four years beginning with the date of the breach”. In August 2006 the second respondent submitted under section 191(1)(a) for a certificate of lawfulness for use of the building as a dwelling house, contending that the four year time limit in section 171B(2) was applicable and had elapsed.

The appellant initially had denied that the building constructed was a dwelling house, maintaining that a ten-year period of enforcement applied under s 171B(3) of the Act and refused the certificate. A planning inspector upheld the second respondent’s appeal, finding that however the building was classified, it had been in use as a single dwelling house, and this was sufficient to bring section 171B(2) into operation. The High Court, in turn, overturned the inspector's decision, the judge holding that since there had never been any intention to use the building other than as a dwelling house, this meant there had not been a change of use under section 171B(2). The Court of Appeal reversed the judge's decision, finding that there had been a “change of use” within section 171B(2) such that immunity from enforcement was established.

Lord Mance, delivering the lead judgment of the Supreme Court, held that use as a dwelling house should not be judged on a day by day basis, but on a broader and longer term basis. Dwelling houses were frequently left empty for long periods without any question of abandonment or of their not being in use. Change of use to residential development could take place before the premises were actually “used”, but not before the operations had been begun to convert to residential accommodation. It was artificial to say that a building’s use was as anything other than a dwelling house, when its owner had just built it to live in and was about to move in within a few days’ time. Even if the planning permission were to be treated as having been initiated or begun, it had not been implemented in any further or substantial respect; so the building constructed was not a building which could be regarded as having any permitted use. Therefore, there had been no relevant change of use so as to bring the building within s 171B(2).

Noting that the law should serve the public interest, the question then was whether it could have been the intention of the legislator that a person conducting himself like the second respondent could invoke the benefits of the Act. Although his conduct was not identifiably criminal, it had consisted of positive deception in matters integral to the planning process and had been intended to, and did, undermine the regular operation of that process. He would be profiting directly from that deception if the passing of the normal four-year period for enforcement which he brought about by the deception were to entitle him to resist enforcement. The apparently unqualified statutory language could not contemplate or extend to such a case. Sections 171B(2) and 191(1)(a) were thus inapplicable to the instant case.

The Supreme Court allowed the appeal and set aside the grant of the certificate of lawfulness.