A guide to garden room planning permission

If you’re thinking about adding a garden room, one of the first questions is usually whether planning permission is required.

The good news is that, in most cases, garden rooms fall under permitted development rights, meaning planning permission is not usually required provided certain rules are followed.

Understanding the difference between planning permission and building regulations — along with the situations where approval may be needed — can help you move forward with confidence.

Planning Permission vs Building Regulations

Planning permission and building regulations are often confused, but they deal with different things.

Planning Permission

Planning permission relates to how buildings and land are used and how a structure may affect the surrounding area.

This includes things such as:

• the size and position of the building

• its height

• how much garden space it occupies

• how the building will be used

Building Regulations

Building regulations focus on how a building is constructed and whether it meets current standards for:

• structural safety

• insulation and energy efficiency

• drainage

• ventilation

• electrical safety

Depending on the size, location, and intended use of your garden room, you may need one, both, or neither.

When planning permission is not usually required

Most garden rooms are classed as permitted development, meaning planning permission is normally not required if certain conditions are met.

In general, planning permission is not usually required if the garden room:

• is used for incidental purposes such as a home office, gym, studio, hobby room, or garden salon

• is single-storey

• is positioned behind the principal elevation of the house

• does not cover more than 50% of the land surrounding the original house, including other outbuildings

• is not used as a separate self-contained living space

• does not include satellite dishes or antennas

Garden room height restrictions

Height restrictions are one of the most important permitted development rules.

If a garden room is positioned within 2 metres of a boundary, the overall height must not exceed 2.5 metres.

Outside of this:

• buildings with a dual-pitched roof can be up to 4 metres high

• other roof types can generally be up to 3 metres high

At Garden Living Spaces, our garden rooms are designed at 2.45m high to sit within the common 2.5m permitted development height restriction when positioned within 2 metres of a boundary, while still maximising internal headroom.

When Planning Permission May Be Required

There are some situations where planning permission may still be required.

This can include:

• listed buildings

• conservation areas

• National Parks

• Areas of Outstanding Natural Beauty

• properties where permitted development rights have been removed

• buildings positioned forward of the principal elevation of the house

• certain outbuildings positioned to the side of the property on designated land

Requirements can vary depending on the property and local authority, so if you are unsure, it’s always best to check directly with your local council before proceeding.

Building Regulations Explained

Building regulations are separate from planning permission and relate to how the building is constructed.

Buildings Under 15m²

Building regulations approval is not normally required if the garden room:

• is under 15m²

• is single-storey

• contains no sleeping accommodation

Buildings Between 15m² and 30m²

For garden rooms between 15m² and 30m², building regulations approval is usually not required if:

• the building contains no sleeping accommodation, and

• it is positioned at least 1 metre from any boundary

At Garden Living Spaces, our garden rooms are designed for incidental garden use and are available in sizes below 30m².

Buildings Over 30m² or Residential Use

Building regulations approval is generally required if:

• the building exceeds 30m², or

• it is intended for sleeping or residential accommodation

Garden Living Spaces buildings are designed for incidental garden use rather than self-contained residential accommodation.

Regulations That May Still Apply

Even where planning permission or building regulations approval are not required, certain regulations may still apply depending on the project.

This can include:

• electrical safety regulations (Part P)

• drainage regulations where plumbing or drainage connections are installed

Depending on the intended use, some homeowners may also choose to include plumbing for sinks or WC facilities. Requirements can vary depending on the setup and local authority, so it’s always worth checking before proceeding.

Important Note for Homeowners

While we’re always happy to provide general guidance based on standard national rules, it is ultimately the homeowner’s responsibility to confirm planning permission and building regulation requirements with their local authority.

Local interpretations, site-specific conditions, and property restrictions can all affect what is permitted.

If there is any uncertainty, we would always recommend checking directly with your local council before proceeding.

Ready to create your perfect garden room?

Use our Garden Room Visualiser to design and price your garden room online, or contact us to discuss your ideas with the team.