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Extensions and Planning Permission

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  • 13-10-2021
Extensions and Planning Permission

Whether this is your first extension project or your third, each project is unique and requires something different. Read over this short article to find out if you need planning permission for your extension project today. 

Do I need planning permission for Extensions?

Put simply, if you want a significant change or development to your property, then you'll probably need some form of a planning application. Any major change to your house or the area of land around the building (curtilages) will require planning permission before development can begin. This can also sometimes include interior extensions, like a loft conversion, for example.

If the proposed extension is less than half of the area of land surrounding your house, then you're okay to continue without former paperwork.

The original house, which is defined as the building as it was in 1948 and onwards, must be considered when you're planning an extension. Also, if you want an extension higher than the original roof, or at least the highest part of it, you must consider an application.

Smaller jobs can still sometimes require planning permission, like in the case of bungalows and other single-storey extensions. For example, if you're considering a rear extension on your single-storey house, then it must meet the Building Regulations and not be higher than four metres.   

It's best to discuss your plans with a designer or architect, so they can advise you on if further approval will be needed. If you fail to complete paperwork, then you can be fined and legally forced to undo all the work you've completed up to that point. 

How to get planning permission

If you don't want to receive this Enforcement Notice, you should get your planning application in before starting any work. To get planning permission, you can contact your local council and speak to the Planning Department. The Planning Authority have experience and will advise you on what is possible and what paperwork is needed.

The design and drawings of your proposed work will also be a key part of getting the planning permission approved. This can be done by a designer or an architect but must show how the original building will be respected and how the proposed extension will benefit not only your house but the surrounding areas without being intrusive. You must also show how the structural integrity has been planned out and how it will be constructed safely. 

There are many different planning permissions options, as they are meant to cover a wide variety of project sizes and types. Once you have the drawing completed, you must provide proof of ownership of the land also. There will also be an application fee, which must be paid upon submission. You'll receive a receipt via email if done electronically, giving you clarity that the permission has been approved. 

Since most people will be working with smaller extension projects, the needed paperwork isn't as grand and scary as bigger projects. You must show how the materials used will complement the original house and how you've considered Nature Conservation, especially if building a rear extension into your garden. 

How big can I build an extension without planning permission?

As we've said, however, there are instances where you're already protected and don't need further permission to build an extension. Permitted Development Rules have been put into place so small pieces of work can be constructed. 

If you live in a detached house, then you're able to build an extension up to 8 metres and six metres in attached houses. It's worth noting the type of property you live in, as most flats (if not all) do not have these rights, and therefore no legal work can be carried out without official planning paperwork. 

It's worth contacting your council if you're unsure, as you may be in a property that doesn't meet these requirements. 

Are there conditions for extending without planning permission?

There are, of course, many restrictions to building an extension without planning permission, as it's advised to get the paperwork done. 

Semi-detached or terraced houses can extend as far as six metres without having to consult neighbours. However, it must be no taller than 4 metres, or you're looking at paperwork being completed.    

Detached houses have to follow the same rules, but they can only extend up to 4 metres from beyond the rear wall. If you've heard of the Neighbour Consultation Scheme, then this will protect you, as you're legally allowed to extend up to 8 metres without permission. Be sure to check, though.    

Any listed property must attain Listed Building Consent, regardless of the scale of the project. This is to ensure that the building and the surrounding land are not disrupted and respected. Any extensions that want to take place on this land should be approved.

Single-storey properties follow the same rules and should be wary of their extensions not being higher than 4 metres. It's more common to see rear extensions, as they're easier to approve.

A front extension has to take into account the road, as do side elevations or extensions. They must not extend beyond the wall of the original house that faces the road and should try to match the appearance of the original property, as not to be offensive. 

Two-storey rear extensions have restrictions and height requirements too. Pitches and eaves cannot extend higher than the original building, and if the building is within two metres of a rear boundary, then the height is restricted to three metres. Any form of nature conservation should be taken into account, and the conservation area should be mapped out if the extension will intrude. 

You should consult an architect or designer as to whether you should apply for planning permission or not, as you could end up in a legal bind otherwise. Be sure to get an opinion on the design of the existing house, as the idea you have in your head may not match and not get approved.


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