Planning guidance
Do you need planning permission for a garden room?
Usually not. Almost every garden room we supply is built under permitted development. Here are the rules in plain English, and the handful of situations where you do need to apply.
Normally permitted development
- Single storey, with a maximum eaves height of 2.5m
- No more than 2.5m total height where it sits within 2m of a boundary
- Positioned behind the principal elevation of the house
- Covering no more than 50% of the land around the original house
- Used ancillary to the home: office, gym, studio, hobby room
Permission usually needed
- Sleeping accommodation, an annexe or anything self-contained
- A building in front of the principal elevation, facing a highway
- To the side of the house in a conservation area
- Over 10 square metres and more than 20m from the house in a conservation area
- Any work to, or in the curtilage of, a listed building
- Homes where permitted development rights have been removed by condition
The 2.5m rule, and why our rooms are designed around it
The single condition that catches most people out is height. Within 2m of a boundary, an outbuilding cannot exceed 2.5m. Every Pent Haus garden room is exactly 2.5m to the top of the roof across all 15 sizes, so you can place it tight against a fence without triggering an application. Both the Astana flat roofline and the Abri, with its 60cm overhang, keep to the same height.
Your local planning authority
Rules are national, but conservation area boundaries and removed permitted development rights are local. These are the authorities across our patch.
Southampton City Council
Conservation areas across Bassett, Highfield and the Old Town.
Portsmouth City Council
Extensive conservation areas in Southsea and Old Portsmouth.
Fareham Borough Council
Covers Whiteley, Titchfield and Portchester.
Winchester City Council
Large conservation area across the city centre and villages.
Eastleigh Borough Council
Covers Hedge End, Botley and Bishopstoke.
Havant Borough Council
Covers Emsworth, Hayling Island and Waterlooville.
New Forest District Council
National Park rules apply in much of the district.
Chichester District Council
South Downs National Park covers part of the district.
Planning questions
This page is general guidance, not formal planning advice. Always check with your local authority before ordering if you have any doubt. Happy to talk it through — get in touch.
Within the rules, and ready in weeks
Every size we supply is 2.5m high by design. Configure yours and see the price instantly.