Is permitted development the same everywhere in Cornwall?

The national rules are the same, but the exceptions are local. Conservation Areas, Areas of Outstanding Natural Beauty, Article 4 directions and conditions on individual properties all narrow what is permitted, and Cornwall has a lot of all four. Always check the specific address rather than a general rule.

Does permitted development mean I can skip building regulations?

No. They are separate systems. A project can be permitted development and still need full building regulations approval, and most structural work does. Planning is about whether you may build it, building regulations are about how it must be built.

Can I ask the council before applying?

Yes. Cornwall Council offers a pre-application advice service, which gives you a written officer view before you commit to a full application. It is often worth it on anything unusual, sensitive or borderline.

How do I know if my rights have been removed?

Look at the original planning permission for the house and read the conditions. Newer estates in particular often carry a condition removing permitted development rights for extensions, outbuildings or hard standing, and it is easy to miss.

Can you check for me?

Yes. Working out the consent route is part of our free first consultation, and we will tell you what applies before any drawings are commissioned.

Guide · Cornwall

Do I need planning permission, or is it permitted development?

This is the first question almost every project starts with, and the honest answer is that it depends on the property, not the project. Two identical extensions on the same street can land in different places, because one house has already used its allowance, sits in a Conservation Area, or has a planning condition on it from when the estate was built. What follows is how to work out which side of the line you are on before you spend anything.

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What permitted development actually is

Permitted development is a national grant of planning permission for certain types of work, so you can build without applying, provided the work stays inside the published limits on size, height, position and materials. It is a set of rules, not an opinion, and the rules are published by government on the Planning Portal. The limits are detailed and they change, so treat any summary, including this one, as orientation rather than a decision.

It applies to houses, not to flats, maisonettes or most converted buildings
It can be withdrawn on a specific area by an Article 4 direction
It can be removed on individual properties by a planning condition, which is common on newer estates
Previous extensions count against your allowance, even if a previous owner built them

Situations in Cornwall that usually mean an application

Cornwall has a high proportion of designated and protected settings, so the exceptions bite more often here than in much of England. If any of the following apply, assume an application until someone confirms otherwise.

The building is listed, in which case listed building consent is a separate requirement as well
The property sits in a Conservation Area or an Area of Outstanding Natural Beauty
The work involves a change of use, for example a barn, a garage into a separate dwelling, or a holiday let
You are building to the front of the house, raising the roof, or adding a balcony or raised terrace
The plot is in the open countryside, near a protected tree, or within a flood zone

How to check properly rather than hopefully

Start with the deeds and the original planning history of the house, which is public on the Cornwall Council planning register. Read any conditions attached to the original permission, because that is where permitted development rights are most often removed. Then check the current national rules on the Planning Portal, and if there is any doubt, apply for a lawful development certificate, which is a formal confirmation that what you are proposing does not need permission.

Why a certificate is worth having even when you are confident

A lawful development certificate is the document a buyer's solicitor asks for. Building under permitted development and relying on your own reading of the rules is fine until you sell, at which point the absence of paperwork can hold up the sale or reduce the price. It is a small cost against the value of the certainty.

Frequently asked

Straight answers.

Is permitted development the same everywhere in Cornwall?: The national rules are the same, but the exceptions are local. Conservation Areas, Areas of Outstanding Natural Beauty, Article 4 directions and conditions on individual properties all narrow what is permitted, and Cornwall has a lot of all four. Always check the specific address rather than a general rule.
Does permitted development mean I can skip building regulations?: No. They are separate systems. A project can be permitted development and still need full building regulations approval, and most structural work does. Planning is about whether you may build it, building regulations are about how it must be built.
Can I ask the council before applying?: Yes. Cornwall Council offers a pre-application advice service, which gives you a written officer view before you commit to a full application. It is often worth it on anything unusual, sensitive or borderline.
How do I know if my rights have been removed?: Look at the original planning permission for the house and read the conditions. Newer estates in particular often carry a condition removing permitted development rights for extensions, outbuildings or hard standing, and it is easy to miss.
Can you check for me?: Yes. Working out the consent route is part of our free first consultation, and we will tell you what applies before any drawings are commissioned.

Not sure which route your project takes?

Send us the address and what you have in mind. We will tell you the likely consent route at no cost.

Free · No obligation

Book your free consultation

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