Do I Need Planning Permission for an Extension in the East Riding?

How big you can extend without planning permission, where conservation areas change the rules, and what Building Regulations approval you'll still need.

If you're thinking about an extension, planning permission is probably your first concern. The good news is that many single-storey extensions don't need it. The rules can be confusing though, and getting it wrong can be expensive.

We build extensions across Hull and the East Riding as part of our renovation and development service, so this is a question we answer most weeks. This guide explains the current rules in plain English. If you'd like us to review your plans, contact us and we'll talk you through them. And if you're weighing up an extension against updating the rooms you already have, our guide to the cost of a new bathroom in Hull is a good place to start budgeting.

The short answer

You often don't need planning permission for a single-storey rear extension in the East Riding. Under permitted development rules, a detached house can usually extend up to 4 metres from the original back wall and a semi-detached or terraced house up to 3 metres. The extension must be no more than 4 metres high. You'll need planning permission if you go beyond these limits, build at the front of the house or live in a flat. Homes in a conservation area also have tighter rules. Whatever the size, most extensions still need Building Regulations approval.

In places like Cottingham and Willerby, planning is handled by East Riding of Yorkshire Council. If you live within the Hull city boundary, it's Hull City Council. The national rules apply to both.

How big can I extend without planning permission?

Permitted development is a set of national rules that lets you carry out certain building work on a house without applying for planning permission. Here are the main limits for extensions in England as they stand in 2026.

A few other rules apply to all of these:

• If the extension is within 2 metres of a boundary, the eaves can't be higher than 3 metres.
• Extensions and outbuildings together can't cover more than half the land around the original house.
• Materials must look similar to the existing house.
• Nothing can go in front of the main front wall facing the road.
• Balconies, verandas and raised platforms aren't allowed.

One thing that catches people out is the word "original". It means the house as it was first built or as it stood on 1 July 1948. If a previous owner already added a conservatory or an extension, that counts towards your allowance.

Do conservation areas have different rules?

Yes. Parts of the East Riding sit within conservation areas, and the rules there are stricter. In a conservation area you'll usually need planning permission for a side extension or any extension of more than one storey. The larger extension scheme (up to 6m or 8m) doesn't apply either. Some streets also have what's called an Article 4 direction, which removes certain permitted development rights altogether.

If your home is listed, you'll need listed building consent for almost any change, inside or out. The quickest way to check your address is to contact East Riding of Yorkshire Council or look at the conservation area maps on its website.

What is prior approval for a larger extension?

Prior approval lets you build a bigger single-storey rear extension than standard permitted development allows. That means up to 8 metres on a detached house or 6 metres on a semi-detached or terraced one. It sits between permitted development and a full planning application.

You send the council the extension details, and they write to your neighbours. If nobody objects or the council decides the objections don't outweigh the plans, you get approval. The council has 42 days to decide. You must have the decision before building starts.

Do I need Building Regulations approval for an extension?

Almost always, yes. Planning permission and Building Regulations are two separate things. Planning is about how the extension looks and how it affects the area. Building Regulations make sure it's safe, warm and built properly. That covers things like foundations, insulation, drainage, fire safety and electrics.

Even if your extension falls under permitted development, it will still need Building Regulations sign-off. A building inspector will visit at key stages, and you'll get a completion certificate at the end. Keep that certificate safe because a buyer's solicitor will ask for it when you sell.

Should I get a Lawful Development Certificate?

It's not a legal requirement but we'd usually recommend it. A Lawful Development Certificate is written confirmation from the council that your extension counts as permitted development. It costs a fee to apply, but it gives you proof if a neighbour complains or a buyer asks questions later. It's especially useful if your plans are close to the limits.

How do I apply for planning permission in the East Riding?

Most people apply online through the Planning Portal, which sends your application to the right council. You'll need drawings of the existing house and the proposed extension, a site location plan and the application fee. A decision on a householder application usually takes around 8 weeks.

It's worth talking to the council or a builder before you submit. Small design changes, such as reducing the depth or roof height, can sometimes bring a project back within permitted development.

Planning an extension?

The rules are there to protect you and your neighbours, but they shouldn't stop you getting the extra space you need. If you're not sure where your plans stand, we're happy to come out, look at the house and give you an honest view before you spend money on drawings.

CHM Yorkshire has been building extensions and renovating homes around Hull since 2014. We're CHAS Elite accredited, fully insured and rated 5/5 on Google. Call 07816 581858 or request your free quote and we'll get back to you within 24 hours.