How much can I extend my house without planning?

We would all love to add an extension or sun room to our home to create more space. But the thought of going through the planning process stops many home owners before they even start. How much can I extend my house without planning?

Yes you can extend your house without planning so get your imagination into gear! Here we explain how much you can extend your house without the need for planning in both England & Scotland.

You can extend your home without the need to apply to planners. But how much can I extend my house without planning?

Rules in Scotland

In Scotland you can add an extension to your house under their ‘permitted developments’. This means you do not need to seek approval from your local planning department. Of course this comes with rules and rear extensions seem to come with far less restrictions and red tape. The rules mainly depend on how many storeys the extension will have.

Single Storey Extensions – Scotland

The Scottish Government rules for single storey extensions are as follows:

Must be located at the back of the house
Must not go back further than 3 metres if it’s a terraced house, or 4 metres if it isn’t
the height of the eaves (where the wall meets the roof) is no higher than 3 metres
Must not be higher than 4 metres, including sloping roofs
Must not cover more ground area than your house does
Must not take up half the ‘curtilage’ – the grounds behind your home
Cannot be within a conservation area (check the Historic Environment Scotland website if your not sure)

If the extension exceeds any of the above limits then an application for planning permission will be needed. In Scotland, you do not need planning permission for a conservatory if it falls within permitted development.

Multi Storey Extensions – Scotland

Here are the rules for multi storey extensions that do not require planning permission:

Must be located at the back of the house
Must be at least 10 metres between the extension and the boundaries of your grounds
Must not be higher than your house (excluding chimneys)
Cannot cover more ground area than your original house does
Must not take up half the ‘curtilage’ – the grounds behind your home
Cannot be within a conservation area (check the Historic Environment Scotland website if your not sure)

Rules In England

England has a very similar process to Scotland. They too have a ‘permitted developments’ scheme which allows you to extend without applying for planning. Yay!

They have a pretty smart interactive planning portal which you can see by clicking here

Single Storey Extensions – England

Here are the keys points to consider when asking How much can I extend my house without planning?

No more than half the area of land around the “original house”* would be covered by additions or other buildings. Sheds and other outbuildings must be included when calculating the 50 per cent limit
No extension forward of the principal elevation or sideelevation fronting a highway.
Materials to be similar in appearance to the existing house.
Maximum height of a single-storey rear extension of 4m.
Materials to be similar in appearance to the existing house.
Side extensions to be single storey. Width of side extension must not have a width greater than half the width of the original house
Side extensions to have a maximum height of four metres and width no more than half that of the original house.
If the extension is within 2m of a boundary, maximum eaves height should be no higher than 3m to be permitted development.
Single-storey rear extensions must not extend beyond the rear wall of the original house* by more than 4m if a detached house; or more than 3m for any other house.
Maximum eaves and ridge height of extension no
higher than existing house.

Conservatories fall under the same planning regulations as any extension or addition to a house.

Multi Storey Extensions – England

Here are the multi-storey rules under the permitted development scheme.

Extensions (including previous extensions) and other buildings must not exceed 50% of the total area of land around the original house.
Maximum eaves and ridge height of extension no higher than existing house. If extension is within two metres of a boundary maximum eaves height should be no higher than three metres to be permitted development.
Extensions of more than one storey must not extend beyond the rear wall of original house by more than three metres or be within seven metres of any boundary opposite the rear wall of the house.
Roof pitch of extensions higher than one storey to match that of the existing house, as far as is practicable.
Materials used in exterior work to be similar in appearance to those of the exterior of the existing house.
Any upper-floor window in a wall or roof slope in a side elevation must be obscure-glazed and nonopening unless the parts which can be opened are more than 1.7 metres above the floor of the room in which it is installed.
No balconies or verandas are permitted development.

Designated Land rules in England

In England there are stricter rules for their permitted development rules if your property is in ‘designated land’ which includes national parks and the Broads, Areas of Outstanding Natural Beauty, conservation areas and World Heritage Sites. If in doubt I would be contacting your local planners to discuss this.

Although planning permission is not required in England & Scotland’s permitted development schemes, I would still advise that you give them a ring anyway. First of all to confirm that you don’t need planning for what you are wanting to do. But also to ensure there are no other necessary approval you may need. They are there to help so always reach out to your local planning department if your in doubt or have any questions.

How much can I extend my house without planning? I think this blog pretty much sums it up. There are plenty options for you to consider to extend your home, which involve no planning permission at all. Just make sure you read up on the rules and understand all the restrictions. Tada!

If your improving and extending your house why don’ t you give your house a name? Here is a good place to start Names for houses with meaning and also this may be helpful too Does naming your house increase the value?

Thinking of selling and have solar panels on your house?