Planning permission

You may need planning permission, even if you are only carrying out small alterations or an extension to your property. This section outlines how to work out whether or not you need to apply for planning permission.

Always get advice from your local planning office if you are unsure whether you need planning permission or not.

When do I need planning permission?
I live in a listed building
I'm building an extension
I am carrying out a roof extension
I am building a garage or carport
I'm converting a house into flats
Other alterations and additions

When do I need planning permission?

You do not always need planning permission. It usually isn't required for changes to the inside of your home, or for small alterations to the outside. for example, installing telephone connections and alarm boxes.

You will usually need planning permission if:

you want to alter or add an extension to a flat
you want to divide part of your home to be used as a separate house
you want to build a separate house in your garden
you want to divide part of you house off to be used as part of a business
the work may obstruct the views of road users

This section only briefly outlines when you may need planning permission. Contact your local planning office or visit the Planning Service site for more detailed information on when you need planning permission.

I live in a listed building

You are more likely to need planning permission if you live in:

a listed building
a conservation area
an area of outstanding natural beauty

You may also need listed building consent if you live in a listed building.

Contact your local planning office for more information on carrying out alterations and extensions to listed buildings.

I'm building an extension

You usually won't need planning permission for an extension if it is within certain limits. These limits depend on:

the size of the house
the size of the extension
the location of the house

Size of house

The size of the house is calculated from external measurements. There is an upper limit of 115m³. Any extension built after 1973 won't count as part of the original volume of the house. You can calculate the volume of your house by using this volume calculator.

Size of the extension

You will usually need planning permission if the extension is more than:

70 m³, or
15% of the original volume of the house

However, if the property is in a conservation area, or is a terrace house you will need planning permission if the extension is more than:

50 m³, or
10% of the original volume of the house

My extension doesn't need planning permission

Even if you extension is within the permitted guidelines there are certain rules you must follow:

the design and materials must be 'in keeping' with the original house
the extension mustn't be closer to the road than the original house
the extension mustn't be higher than the original house
the extension must be lower than 4metres high if it is within 3 metres of your property boundary
the extension and any other outbuildings must be less than half the ground area of the house.

Contact the planning service for more information on rules to follow when building an extension.

I am carrying out a roof extension

You will usually need planning permission if you are installing dormer windows. You usually don't need planning permission if you are simply converting a roof space to provide extra living room. The roof space conversion must be less than 25 m³, or 20m³ in a terrace house.

You will need to get building control even if you don't need planning permission.

I am building a garage or carport

You won't need planning permission if:

the garage is for domestic purposes
the garage isn't nearer the road than the house
the garage isn't higher than 3 metres, or 4 metres if it has a ridged roof

You will need planning permission if you live in a listed building.

A garage is treated as an extension if:

you live in a conservation area
it is within 5 metres of the house

I'm converting a house into flats

You will need to get planning permission because this is considered a 'change of use'.

Other alterations and additions

Planning permission may be required for smaller alterations. Contact your local planning office or visit the Planning Service site for more information on when you need planning permission. Even if you don't need planning permission you may need to get building control approval from your local council.

Building a porch

You wont need planning permission if:

the floor is smaller than 2 square metres
the porch is lower than 3 metres
the porch is further than 2 metres from the road or footpath
the design and materials are in keeping with the original house

Conservatory

You won't need planning permission for a conservatory if you follow the rules for building an extension.

Adding a 'granny flat'

You will need to get planning permission if it is a separate and self-contained unit. If it isn't self-contained you must follow the rules for extensions.

Reroofing

You usually won't need planning permission if you don't increase the height of the roof, and the new roof looks similar to the old one

Walls and fences

You usually won't need planning permission if you want to build a wall or fence up to 2 metres high. If the wall is next to a road you can only build a 1 metre high wall without planning permission. You will always need planning permission to build a wall or fence next to a listed building.

There are rules about getting planning permission for walls or fences in an open plan development. Contact your local planning office for more information.