When You Don’t Need Planning Permission

When You Don’t Need Planning Permission

In many cases, you can extend your home without applying for full planning permission, thanks to permitted development (PD) rights. These rights allow you to carry out certain types of extensions and alterations without formal approval from the council, provided the work stays within strict size and design limits.

Here are some situations where you typically don’t need planning permission:

1. Small Rear Extensions

You can often build a single-storey rear extension under permitted development if it meets the following:

• For terraced or semi-detached homes, the extension can project up to 3 metres from the original rear wall.
  
• For detached homes, this increases to 4 metres.
  
• The height of the extension must not exceed 4 metres, and the eaves height should be no more than 3 metres if within 2 metres of a boundary.
  
• The materials should be similar in appearance to the rest of the house.
  
• The extension must not cover more than 50% of the original garden (as it was in 1948 or when first built, not including any previous additions).
  

2. Side Extensions

Side extensions can also fall under PD if:

• They are single-storey only
  
• They are no wider than half the width of the original house
  
• They are no taller than 4 metres
  
• They stay within 2 metres of the boundary and don’t exceed the allowed eaves height
  

3. Loft Conversions

Loft conversions are often permitted as long as:

• The new space does not exceed 40 cubic metres (for terraced houses) or 50 cubic metres (for detached/semi-detached)
  
• The conversion does not extend beyond the existing roof plane on the front
  
• Any dormer windows are to the rear of the property and set back at least 20 cm from the eaves
  
• Materials are in keeping with the rest of the property
  
• There are no balconies, verandas or raised platforms
  

4. Garage Conversions (Internal Only)

If you are converting an integrated garage into a living space and not altering the external appearance, you may not need planning permission, although building regulations approval will still be required.

When You Do Need Planning Permission

While permitted development covers many types of extensions, there are several scenarios where you’ll need to go through the full planning application process.

You will likely need planning permission if:

1. Your Property Has Restrictions

Some homes do not benefit from permitted development rights, including:

• Flats and maisonettes
  
• Listed buildings
  
• Homes in conservation areas, national parks, Areas of Outstanding Natural Beauty (AONB) or World Heritage Sites
  
• Homes in areas where permitted development rights have been removed by the council via an Article 4 Direction
  

If you’re unsure whether your home falls into one of these categories, our team can check this for you as part of your online consultation.

2. You’re Building a Large or Complex Extension

Even if your home qualifies for permitted development, certain types of work exceed the PD limits and will require full planning approval:

• Rear extensions that are more than 3 or 4 metres deep
  
• Extensions that are more than one storey and close to a boundary
  
• Extensions that are higher than the current roof
  
• Extensions to the front of the house
  
• Any extension that significantly alters the appearance of the home, such as using different cladding or materials
  

3. You’re Making Changes to the Roof

Alterations to the roof that go beyond PD limits, such as raising the roof height, adding front dormers, or installing roof terraces or balconies, will usually need planning permission.

4. You Want to Build a New Outbuilding

While many garden rooms and outbuildings are covered by PD, planning permission is needed if:

• The outbuilding is intended for living accommodation
  
• It takes up more than 50% of the garden
  
• It is closer to a road than the main house
  
• It exceeds 2.5 metres in height within 2 metres of the boundary
  

Need Help Checking Your Project?

It’s not always obvious whether your extension needs permission. The best approach is to get advice from an architectural professional early on, especially if your home is in a conservation area or has had previous extensions that may affect what’s allowed.

At Online Drawing UK, we offer:

• Free consultations to assess your project’s planning needs
  
• Affordable planning application drawing packages
  
• Support with Lawful Development Certificates to confirm PD rights
  
• Full submission and management of planning applications where required
  

We make the whole process straightforward and remote, no need for site visits, and no surprises later down the line.