Certificate of Lawfulness for a Sauna and Gym in the Surrey Green Belt
Certificate of Lawfulness for a Proposed Development from Mole Valley District Council for a large outbuilding in the Surrey Green Belt containing a sauna, gym and storage, by establishing the use was incidental rather than ancillary to the dwelling.
COL APPROVALSMOLE VALLEYSURREYGREEN BELT
Andrew Ransome
7/4/20262 min read
In 2020, Mole Valley District Council approved a Certificate of Lawfulness for a Proposed Development confirming that a large outbuilding in the Surrey Green Belt — containing a sauna, shower room, gym and garden storage — constituted permitted development.
My case turned on the critical planning distinction between an 'incidental' use, which falls within permitted development rights, and an 'ancillary' use, which requires formal planning permission — particularly important in a Green Belt location where ancillary outbuildings of this scale would face significant policy resistance.
Certificate of Lawfulness in Mole Valley, Surrey
I secured a Certificate of Lawfulness for a Proposed Development (CLOPUD) from Mole Valley District Council for a large outbuilding in the rear garden of a dwelling in the Surrey Green Belt.
The building was over 100 sq m in floor area and contained a sauna, shower and bathroom facilities, a gym, and garden storage.
The application arose after the building had been constructed and was subject to an enforcement investigation by the Council's planning enforcement team.
The key legal question in this case was whether the proposed use of the outbuilding fell within the definition of an 'incidental' use — in which case permitted development rights under Part 1 of the General Permitted Development Order applied — or whether it constituted an 'ancillary' use, which would require formal planning permission and, in a Green Belt context, would face near-certain refusal.
The distinction is a nuanced but important one.
An incidental use is one that is subordinate in nature and secondary to the primary residential use of the dwelling — something enjoyable but not essential, such as a hobby room, workshop or storage.
An ancillary use, by contrast, is one that involves an activity which could ordinarily be carried out within the dwelling itself, such as cooking or sleeping.
Where an ancillary use is proposed in a new outbuilding, a full planning application is required. In a Green Belt location with restrictive local policies against large outbuildings, that would have been very difficult to secure.
My planning argument successfully advanced was that a sauna with associated shower and bathroom facilities, together with a gym and garden storage, constituted an incidental use reasonably required for the enjoyment of the dwelling — not an ancillary use of a residential character.
Mole Valley District Council accepted this analysis, the enforcement investigation was closed, and the Certificate was granted.
Planning Application Advice
If you have built or are considering building an outbuilding and are unsure whether it falls within permitted development rights, a Certificate of Lawfulness provides certainty and legal protection. I can advise on the incidental/ancillary distinction and manage the application. Contact me to discuss your project.
Andrew Ransome MRTPI - Email: andrew@andrewransome.co.uk
About me
Andrew Ransome is a Planning Director and a Chartered Member of the Royal Town Planning Institute (RTPI), with more than two decades of experience in town planning.
He specialises in delivering strategic planning solutions for complex developments across both rural and urban environments, helping clients navigate planning challenges and unlock development opportunities. Connect with Andrew on Linkedin.
Certificate of Lawfulness Successes
Permitted Development Information
Get in touch for planning advice: Email: andrew@andrewransome.co.uk
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