In recent years, the rules regarding extensions and planning permission has been somewhat relaxed in order to make it easier for homeowners to really make their property theirs, meaning there’s more of a lean towards improving over moving, which is great news.

You may have seen us mentioning permitted development in previous posts, but it’s such a useful topic that we can’t stop ourselves from sharing it with you.

At the moment, permitted development means that you can build an extension without planning permission of up to six metres, or eight metres if you have a detached house.

However, there are still things you need to consider! Let’s take a look at some of the things that you’ll need to keep on your checklist when it comes to permitted development.

Firstly, what type of property do you have? At the moment permitted development only covers houses. So, flats, maisonettes, bungalows etc. won’t automatically be covered by permitted development. Make sure to check if your particular property has undergone any change of use or even been converted into a house in the past as this may affect your rights to permitted development.

When was the last time the home was extended? If the home has been extended in the past, this may eat into your permitted development allowance. Understandably, permitted development can only cover so much, and while it may not have been you as the current owner who last extended the home, a line has to be drawn somewhere, so it’s worth checking with your local authority.

Do you live on protected land? Properties that reside on conservation areas, national parks, work heritage sites etc. will more than likely not fall within permitted development. It could be that you need to apply for planning permission the old-fashioned way through your local authority or that your permitted development rights have been restricted. It’s a similar story for if your property is listed too, so it’s best to investigate this one further.

So up until now we’ve discussed how your property might block you from being able to take advantage of permitted development, but will the type of extension you’re getting affect it too? Short answer, yes. Let’s have a look then.

If you’re looking to extend the front of your property, this is not allowed under permitted development, however this doesn’t mean that it isn’t possible, you’ll just need to apply for planning permission from your local authority.

How about side extensions? There are a few conditions including:

  • It must not front onto the road
  • Must be single storey
  • Max 3m out from the original house
  • Must not be more than half the width of the original house

Rear extension maybe? The rules differ between single storey and two-storey extensions.

When it comes to a single storey extension, you can extend up to six metres or up to eight metres if you have a detached house. For the larger end of these extensions, you’ll need to get support from your neighbours, objections may result in obstacles for your plans.

Now let’s look at two storey rear extensions, there are a lot more parameters that the build needs to meet in order for it to still be able to fall under the permitted development act. 

  • Firstly, the height of the structure must not exceed that of the existing house. However, if the building is within two metres of a boundary, the height can be restricted to 3 metres. 
  • Under permitted development rules, you can extend up to three metres from the original house, but it must be more than seven metres from the rear boundary. 
  • The materials for a two-storey extension typically should be of similar appearance to that of the existing house, however this can change from region to region so would be worth checking this one with your local authority.
  • This advice does not transfer to two-storey side or front extensions.
  • The placement of windows and doors will also need to be double checked with your local authority to make sure you’re not accidentally encroaching on your neighbours privacy.

We’ve only really touched on the surface of what should be considered when planning to extend your home without planning permission, your main method will be if your plans do fall within permitted development. This list is by no means exhaustive, and we would highly recommend checking the government website for more detailed information.

When we set about designing our HAB’s, it was important to us to make the process as simple as possible. We made sure that our selection had something for most and also that each of our HAB’s would sit within permitted development for the majority of people. If you have any doubts about whether you need planning permission or not though, we make sure to do an assessment at every site visit that is booked with us. If it happens that we recommend you get planning permission, we will build this into the price of your HAB for you.

If you have any questions or would like to book a consultation to discuss your plans with us, why not send us an email? We make sure to be as responsive as possible with the majority of queries responded to by the end of the next working day 

Exterior Example - Living Room Layout - Hab 2 Prefab Extensions
Hab 2 Interior Example - Living Room Prefab Extension

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We can install our prefab extensions anywhere the UK including London, Oakham, Manchester, Northampton, Leicester, Coventry, Cambridge, Bedford, Lincoln, Birmingham and more.