Specific Planning Rules for Single-Storey Rear Extensions

Are you considering a single-storey extension for the rear of your property? To ensure your project meets permitted development rules, you'll need to understand these specific planning guidelines:

How Far Can Your Extension Project? (Standard Limits)

When planning your single-storey rear extension, you must ensure it does not extend beyond the original rear wall of your home by more than these maximum distances:

• If you own a **detached house**, you cannot extend your new single-storey rear extension more than **four metres** beyond the original rear wall of your home.

• For **any other type of dwelling** (such as a semi-detached or terraced house), you cannot extend more than **three metres** from the original rear wall.

Building a Larger Extension? (Increased Limits with Prior Approval)

You might be able to build a significantly larger rear extension, but this comes with specific conditions and requires an application process:

• This increased allowance applies only if your property is **not situated on 'Article 2(3) designated land'** (these are typically sensitive areas like National Parks, Areas of Outstanding Natural Beauty, or conservation areas) **or within a Site of Special Scientific Interest**.

• Under these conditions, if you have a **detached house**, you could extend up to **eight metres** from the original rear wall.

• If your home is **any other type of property**, the maximum distance your extension can project is **six metres** from the original rear wall.

• Crucially, for any extension that uses these increased limits, you **must submit a 'prior approval' application** to your Local Planning Authority (your local council's planning department) before starting work.

What About Height?

Regardless of its length, a single-storey rear extension must not exceed a total height of **four metres** at any point.