Do I need planning permission for a timber garden office?

In England, garden offices under 15 m² with maximum 2.5 m eaves height typically fall under permitted development rights and do not require planning permission. Buildings between 15–30 m² may qualify if they meet additional criteria: single storey, no sleeping accommodation, not forward of the principal elevation, and within height limits (2.5 m eaves, 3.0 m ridge for flat roof, 4.0 m for pitched within 2 m of boundary).

In England, garden offices under 15 m² with maximum 2.5 m eaves height typically fall under permitted development rights and do not require planning permission. Buildings between 15–30 m² may qualify if they meet additional criteria: single storey, no sleeping accommodation, not forward of the principal elevation, and within height limits (2.5 m eaves, 3.0 m ridge for flat roof, 4.0 m for pitched within 2 m of boundary). Buildings over 30 m² or intended as separate dwellings (ADUs) almost always require full planning permission.

Why this matters

This question relates to Prefab Timber Cabins: Garden Offices, ADUs & Granny Annexes, which covers the broader topic in detail. Understanding this specific aspect helps architects, builders, and timber dealers make informed specification decisions.

For full context and additional technical detail, see our comprehensive guide:

→ Prefab Timber Cabins: Garden Offices, ADUs & Granny Annexes

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About this answer

This answer is part of the PuurModulair Knowledge Base — comprehensive timber specification guidance for architects, builders, and dealers across the UK, EU, and Scandinavia.