Planning Permission for Garden Projects: What to Know

Kerb appeal and a tidy garden attract tenants and buyers, but be careful how much you improve your plot without permission, as you may risk a hefty fine.

Many homeowners and landlords must balance adding value by tweaking outdoor spaces and breaking strict planning laws.

Councils can penalise green-fingered gardeners up to £20,000 if they plough ahead with improvements without planning permission.

Paving over tatty grass, laying decking, or erecting an oversized gate without planning permission can all result in fines, although most councils will accept a retrospective planning application.

Height restrictions

Depending on their size and location, timber garden structures like outside rooms, sheds, greenhouses, and garages require council approval.

For example, if you erect a shed or garage less than two metres from the garden boundary, the maximum height allowed is only 2.5 metres. Moving the building more than two metres from the boundary raises the height limit to 2.5 metres at the eaves and an overall height of four metres for a dual-pitched roof and three metres for a flat roof.

Significantly, the building or buildings cannot add self-contained living space, have an antenna, or cover more than 50 per cent of the plot. The building should have a floor area of 15 to 30 square metres.

Although councils can grant retrospective permission after work has started, they can also issue enforcement notices. These notices are orders to demolish or remove any improvements and to return the garden to its original state.

Rules for decking, gates and driveways

Some works, such as converting a garage into a living space, may be subject to building control regulations rather than planning.

Here are some common garden improvements that need planning permission:

• Installing decking that is more than 30 centimetres above ground
• Installing decking that covers more than 50 per cent of the garden
• Fitting gates, fences or walls more than a metre high that open onto a road or two metres high elsewhere
• Paving a driveway with concrete or an impermeable layer, like tarmac, that measures more than five square metres without a run-off for water.

Difference between building regulations and planning

Building control regulations set standards for the design and construction of buildings, including personal safety, access for the disabled and energy performance.

Planning rules cover how a building or land is used, the look of buildings, access to roads and a development’s impact on the environment.

In many cases, garden works may need planning permission and to comply with building control regulations.

Councils may enforce both sets of rules more strictly if a property is listed or near a listed property or conservation area.

To learn more about planning permission and building control regulations, visit the government’s Planning Portal or contact the local council.