Do I Need Planning Permission for an Outbuilding?

The Short Answer

Most outbuildings in England do not need planning permission. Garden sheds, workshops, home offices, and similar structures can usually be built under permitted development rights when they are incidental to the house and stay within Class E size and placement limits.

Permitted Development Limits

Not forward of the principal elevation of the house (so usually rear or side garden, not the front)
Total area covered by outbuildings and other additions does not exceed 50% of the curtilage
Single storey with maximum eaves height of 2.5 metres
If within 2 metres of a boundary, maximum overall height is 2.5 metres
If more than 2 metres from boundaries, maximum 4 metres for a dual-pitched roof or 3 metres otherwise
Incidental use only — not sleeping accommodation or a self-contained living space
No veranda, balcony or raised platform

Home Offices and Garden Rooms

A garden office is treated the same as any other outbuilding. As long as it meets the limits and is used as a home office rather than sleeping or living accommodation, it is often permitted development.

When You Need Planning Permission

Forward of the principal elevation (for example in the front garden)
Exceeds size or height limits
Used as sleeping accommodation or a separate self-contained dwelling
Property is a listed building
On designated land where Class E rights are restricted (for example side of the house)
PD rights removed

Conservation Areas and Listed Buildings

Listed buildings and conservation areas have restricted or removed permitted development rights. On designated land, outbuildings to the side of the house are often not permitted development, and further local restrictions may apply.

Building Regulations

Planning permission and building regulations are separate. An outbuilding with electrics, heating, plumbing or structural foundations may still need building regulations approval even when planning permission is not required.

Check Your Specific Project

Planning rules change and can vary by location. Height, boundaries, intended use and designated land status all matter. Confirm with your local planning authority, or use our free checker for your specific project.