Two Storey Extension Plans

Some two storey extensions can be built without needing planning permission, under what are known as “permitted development rights“, however, there are several restrictions. If your proposed plans do not meet these restrictions, then a planning application will be required.

Restrictions under permitted development rights for home extensions include that:

• No more than 50% of the curtilage of the dwelling will be covered by buildings (excluding the original dwelling).
• No extension will exceed the height of the highest party of the roof of the existing dwelling.
• The eaves should not exceed the height of the existing dwelling’s eaves.
• If the extension is within 2m of a boundary, the eaves height should not exceed 3m.
• The extension should not include a balcony or raised platform.
• Materials that match the existing should be used.
• They must be at the rear of the property.
• The property is not designated under Article 2(3) land. This most commonly means that it is not in a conversation area or an area of outstanding natural beauty (AONB), but there are other types of land and areas where permitted development rights do not apply.

This is not an exhaustive list, and there are other considerations as well. We would recommend reading the Planning Portals guide to Permitted Development Rights to get a good understanding of whether your proposal needs planning permission.

If your proposed two storey extension doesn’t meet these criteria then you will need to apply for planning permission.

Our advice is that even if your proposed two storey extension falls within permitted development rights, that you apply for a Lawful Development Certificate which will confirm in writing that your extension meets permitted development. This will make selling the property considerably easier later on.

A two storey extension will be a good idea if you want to add space to both storeys of your house. Commonly this will include creating an additional bedroom or increasing the size of existing bedrooms. This will increase your home’s value.

A two storey extension will also allow for a larger living space downstairs, perhaps for creating an open plan living space, or increasing natural lighting.

Most commonly, two storey extensions are either constructed entirely to the rear of the property, or as part of a wrap-around extension.

The first option will create additional space to the rear of your property and typically allows for the creation of a larger, open plan living space on the ground floor, and for another bedroom on the first floor.

A wrap-around two storey extension will allow for the same as a rear two storey extension, but adds even more space and can completely transform the space and feel of your home.

Both options are great, and it depends on the specific nature and characteristics of the property, as well as your budget for the works, as to which option would work best for you.