Planning permission for a garden office
Usually no application needed at all — if you respect the Class E limits. Height is the variable that causes the trouble.
Class E: the garden building rights
Outbuildings "incidental to the enjoyment of the house" — offices, gyms, studios, stores — are the textbook Class E case. Limits apply to height (2.5 metres within 2 metres of a boundary), coverage (no more than half the garden), and siting (not forward of the house).
“This provides permitted development rights within the curtilage of a house for: (a) any building or enclosure, swimming or other pool required for a purpose incidental to the enjoyment”PD technical guidance, Class E · full text in the library → · official source →
Where it tightens
In conservation areas, buildings at the side of the house lose Class E rights, and anything visible above fence lines invites scrutiny of the area's setting. "Incidental" also matters: a garden office is fine; a self-contained annexe with sleeping accommodation is not incidental and needs permission.
The pattern in refusals is consistent: height and forward siting. A garden office that sits low and defers to the boundary passes almost by construction.
See it in a complete report
In our Richmond example, 77 of 85 decided outbuilding applications within 1 km were approved — 91%, the most-approved project type we measured.
General guidance ends here. Your property is specific.
The free check reads the designations on your exact property in seconds. The full report applies the policies above — and your council’s own Local Plan — to your project, with every quote verified against its source.