Is your home getting more crowded around the build up to Christmas? Does it leave you wishing that you simply had more space to fit the family in your kitchen or living area? Thankfully help is at hand. Utilise that dead space or expand your home outwards with a side extension! We’ve put together a helpful article on everything you need to know about side extensions. Here it is.
What are side extensions?
Side extensions are essentially a project that increases the square meterage of your home to the sides rather than front or back, typically into an alleyway at the side. Victorian or other period buildings often are seen with side extensions due to the design of the build. Typically very small in nature, some homeowners choose to combine a side extension with a rear extension to create a wraparound, as shown on the image below.
You can also choose between single and double storey side extensions, even opting to build over a garage although the foundations and walls may not be strong enough to build over this due to the added weight.

Why would you go for a side extension or wraparound?
There are a lot of reasons to opt for a side extension or wraparound! You could:
- -Add living space if you do not have a garden or a rear extension is not possible. An average side extension adds 25 square metres!
- -You can redesign your kitchen or living room
- -Utilise ‘dead space’ in alleyways that are seldom used
- -Add property value up to potentially £60,000!
As any property with a side alley (including ground floor flats, new builds and investment properties) can opt for a side extension, why wouldn’t you take the chance to develop your home’s living space and property value?

There are however strident rules over how large a side extension or wraparound extensions can be, or whether you would need planning permission. It is also worth noting that not every home will be able to increase their value by as much as £60,000, as this depends on the ‘ceiling value’ of homes. Homes are also affected by the area, local amenities, access to shops, schools, services as well as the condition of the rest of the home. However, even if it is not as much as £60,000, it surely is worth a trip to the Estate agents to see just how much it can benefit you. Another good gauge is by looking at houses on your street with extensions, and then heading to Zoopla or Rightmove to see their recent sold price information.
Here are some of the rules and factors to consider when planning your side extension:
- -If you have a semi detached home and you are planning a two storey extension, your local council may ask you to keep it a certain distance from your neighbours to prevent a ‘terracing effect’.
- -If you are planning to extend a listed building, you will need to justify why it is a good idea and almost certainly need listed building consent. However, if there is a reason such as the original design had a larger width or side extension, you can justify that you are keeping with the character and history of the original design.
- -If you live in a conservation area, area of outstanding natural beauty or national park your design would have to be in keeping with the character of the surrounding countryside.
Similarly you will not qualify for permitted development if:
- -You are planning on using the extension as a self contained space, as this is essentially creating another abode.
- -You want to extend your proposed extension more than half the width of the original house.
- -You wish to raise the proposed roof size higher than the highest part of the existing roof, nor can you elevate the eaves higher than what already exists.
- -You wish to develop your single storey side extensions more than 4 metres high.
- -Your proposed extension is taller than 3 metres or within 2 metres of the property’s boundaries.
- -Changing the original design of your roof.
- -You want to use a different material on the outside of the building, as everything should match.
Extension over a rear extension
You can also add a side extension to your rear extension if you lived in a terraced house. This is sometimes referred to as an infill extension.
There are however some rules on how far you can extend. For Detached houses, your side extension must not extend more than 4 metres to the rear. For Semi detached or terraced houses, you cannot extend more than 3 metres to the rear.
Pitfalls to avoid
Some common errors we have seen usually are in finding the correct architect and structural engineer, or in checking extension plans for assumptions and whether this will require planning permission. To help alleviate this, we have a few questions you can ask a prospective architect:
- Ask about their experience. You need to ensure that your architect has the expertise you require and what similar projects they have worked on to get a feel for this.
- What is their style? Similarly, you need to ensure that the style of your project is in alignment with previous architect’s projects. Ask about their style to ensure they can encapsulate your dream design.
- Do they envision any additional fees needed for planning permission or building regulations approval? As single storey extensions can average at £1,500- £2,500 per square metre, or £1,750 – £3,000 for double storey extensions you need to ensure you have the budget for this. Typically you can expect to pay around £12,000 for an architect or structural engineers fee, and for double extensions around £15,000 for design, planning permission and building regulations approval.
Our top tips
In order to get your side extension or wraparound just perfect, here are some of the top factors to consider when planning your side extension.
1) Are you going to break down the wall and make it a wider living space or will it be self-contained like a granny flat? Being crystal clear on what this space will be used for can help inform your planning. Will this be an extension to your kitchen or living room? Will you use this as a flat for Gran or even a storage space? For example if this will be occupied, you will want to consider the following.
2) Painting and decorating – Will the extension have the same colour scheme as the rest of the home? Will it be different as a self contained space? Ensure that you are able to source the correct match of paints for a seamless finish, or even start over and re-paint the whole kitchen!
3) Windows – How much natural light do you want to flow into your new space? You can give the appearance of even more space by installing new double glazed windows. If you live in West Yorkshire, our sister company Bingley Windows & Glass can assist you with this.
4) The type of roof – for single storey extensions, you also have the option of a flat roof which is substantially cheaper. However, in comparison to pitched roofs can be less weather resistant as water doesn’t run off the roof as easily.
Contact Us
There we have it, everything you need to know about side extensions. If you have any questions about planning a side extension or are looking for a construction company in West Yorkshire to accomplish this, contact us today on 01535 653530 or fill out our online contact form.