The usual reasons given by householders to justify proposals for enormous outbuildings include the accommodation of snooker tables, gym equipment and home cinemas. A recent appeal decision indicates that the list has now been extended to include home offices (DCS Number 400-030-497).

The inspector in this case recorded that “The GPDO at Article 3, Schedule 2, Part 1, Class E, paragraph E (a), grants planning permission for the provision of an outbuilding within the curtilage of a dwelling, provided it is required for a purpose incidental to the enjoyment of the dwelling as such and subject to the limitations on size, height and location set out at paragraphs E.1 to E.3.” He reasoned that the outcome of the appeal turned on whether the outbuilding could be considered as being required for purposes incidental to the enjoyment of the dwelling as such. In making an assessment in this respect, he recorded that relevant case law, Emin v SSE & Mid Sussex DC [1989], confirms that regard should be had to the use to which it is proposed that the outbuilding would be put and of the nature and scale of that use in the context of whether it is a purpose incidental to the enjoyment of the dwelling. He explained that the physical size of the outbuilding in comparison to the dwelling can be an important consideration but would not by itself be a conclusive factor. It is necessary to identify the purpose and incidental quality in relation to the enjoyment of the dwelling, he went on, and answer the question as to whether the outbuilding is genuinely and reasonably required or necessary in order to accommodate the proposed use or activity and thus achieve that purpose. 

The inspector related that the appeal property comprised a substantially enlarged detached dwelling in spacious grounds. The outbuilding would contain a home office and home gym, together with an entertainment room including a snooker table, craft studio and home cinema.

In the context of a dwelling, the inspector further explained, an incidental use would generally be regarded as a subordinate activity connected with the running of the dwelling or with the domestic or leisure activities of the persons living in it but would not include use as primary living accommodation. It is largely for the occupants of the dwelling to determine what incidental purposes they propose to enjoy, he continued, subject to a test of reasonableness, and he judged it not unreasonable for occupants of a dwelling to wish to work from home. In his view, a home office is more likely to be an incidental use rather than an integral part of the ordinary residential use as a dwelling. 

The inspector found that there was nothing to suggest other than that the interior space of the dwelling was already fully utilised, as claimed by the appellant. Whilst the inspector understood that two of the occupants already worked from home, he judged it unlikely that the space and range of facilities they required to do so efficiently for a sustained period, for example in response to the COVID-19 pandemic, could be provided in the dwelling. A home office, he reasoned, was also likely to require a location away from sources of noise and disturbance, such as a living room or kitchen. In the context of a family dwelling of the size before him, accommodating some or all of the activities proposed within the existing structure was unlikely to be a practical option, he found. As a result, he was satisfied that the activities for which the outbuilding was required could not properly be accommodated within the dwelling.

The inspector decided that the outbuilding was genuinely and reasonably required for purposes incidental to the enjoyment of the dwelling and would not be of a size that was excessive for its purpose. He concluded that the appellant had shown that the outbuilding was granted planning permission by Article 3, Schedule 2, Part 1, Class E of the GPDO.

There is a section on domestic curtilage home offices at 12.838 of DCP Online.