A garden room or shed may be permitted development in England when it qualifies as an incidental outbuilding and meets the applicable conditions. Calling a building a garden office does not settle its planning status: the intended use matters.
How high can an outbuilding be?
The usual Class E limits are single storey, eaves up to 2.5 metres and overall height up to 4 metres for a dual-pitched roof or 3 metres for another roof. Within 2 metres of the property boundary, overall height is limited to 2.5 metres.
It cannot sit forward of the principal elevation. Additions and other buildings together cannot cover more than half the land around the original house. Existing development counts.
Read the Planning Portal's full outbuilding conditions. Height alone does not establish eligibility.
Can you use it as an annexe or separate home?
Class E does not authorise separate self-contained accommodation. A building's actual use must be incidental to enjoyment of the house. Establish the intended use before ordering a garden building or commissioning drawings.
Describe who will use the space, what they will do there and whether it is intended for independent occupation. A supplier's generic description cannot answer those property-specific questions.
Where are rights restricted?
Designated land has additional location and size restrictions. Class E does not permit outbuildings within the curtilage of a listed building. Flats and some houses created through permitted development are excluded. Planning conditions or Article 4 directions may remove relevant rights.
What should you check before buying a garden room?
Gather the proposed footprint, roof height, distances to boundaries and existing buildings. Include decking or other associated work in your description. Keep the supplier's dimensioned specification so it can be compared with the proposed position on your plot.
Find your planning authority for the register and local information. If the site slopes or the boundary is uncertain, flag that before relying on an approximate measurement.
Check the route for your property
Start a free property check, or read about a lawful development certificate if you want formal confirmation of the proposed scheme.
Our permitted development overview links the other home improvement routes. Separately check building regulations requirements; permitted development does not resolve them.