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Home Extension Ideas | A Complete Guide

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Many homeowners are deciding against moving and extending their property instead. Moving home is expensive and so more and more people are deciding to extend their homes instead of moving into a new one. With that in mind, we’ve put together a guide with some helpful home extension ideas, along with what you can expect to pay and how to go about extending your property.

Home extension ideas reasons

Home renovation projects that include extensions are seen by many as a way to add a new lease of life to their house, and homeowners extend their homes for lots of reasons. Some want additional space, while others are keen to increase the value of their home. 

Home extension ideas that could increase house value

For some homeowners, the idea of increasing their home’s value via a house extension is a bonus rather than the sole reason for adding additional space. Others, however, do it solely to increase the value of their home. This is especially true for buy-to-let landlords, who may decide to add another bedroom to a property and increase its rental value. A single-story extension can add around 10% to the value of your home. So if your property was initially worth £350,000, adding 10% would take its value to £385,000. You can use different tools to determine if the home extension idea you have in mind is worth it, you could use for example an extension value calculator or you could even look into a home extension loan.

Extension Value Calculator

Additional space

One of the most common ideas for a home extension is to create more space in the house. Adding another room is more cost-effective than moving home and adds another dynamic to your property. Many people who want to upsize look at the possibility of adding another room before looking for a new house.  


Some homeowners want to be creative with their space and do so by adding an extension. For instance, they may decide to add a workshop to the property so they can focus on their personal projects, be it art, design or anything else creative. 

Common home extension ideas

Loft extension

Number one of the home extension ideas is a loft conversions, they can add up to approximately 10% to the value of a home. While increasing the size of your house via another bedroom or bathroom. Or you can convert a loft into a games room, cinema room or another bedroom for your children. Depending on the type of loft conversion you do they can start from around £30k and rise.

Kitchen extension

Many homeowners wish they had a larger kitchen and are looking at ways to either renovate the kitchen or extending their current space. Most people add a home extension to the back of their property, using bi-fold doors opening up to the garden. Not only will the home look more contemporary, but it’ll also help bring the outside in and improve the property’s overall aesthetics. Average kitchen extensions cost between 10% and 20% of a property’s value. 

Converting the garage

There’s a lot you can do with a garage. For instance, garages attached to your property can be converted into another bedroom or even a second living room. At the same time, a stand-alone garage can be transformed into a creative space like a workshop, a gym or a home office. Single garage conversions cost a maximum of £10,000, while double garages are closer to £20,000. For a more comprehensive conversion with insulation, heating, and basic plumbing, you can expect to pay between £20,000 and £40,000.

Add a utility room

Many properties don’t have a utility room or only a small one for the basics, such as a washer-dryer. Home extension ideas like an extension down the side of the property is popular with large families that want to dry their clothes, and it rarely compromises the garden. Utility rooms can also be great for dogs and other pets, acting as a wet room if they get muddy after a few hours in the park. 


Conservatories are popular and cost-effective ways of extending the downstairs of your home. They cost between £5,000 to £15,000 for a basic, small conservatory with standard materials and finishes and can add 5% to your home’s value. Before deciding on a conservatory, consider what you’d like to use it for. Will it be a year-round space or just for the summer? An all-year-round conservatory costs more as it needs to be insulated, so it’s warm during the colder months. 

Homeowner Loan Quotes

Are there any restrictions to my home extension?

What size extension can you build without planning permission? Additions or extensions to your house is generally considered as a permitted development. That means you won’t need to go obtain planning permission as long as your home meets the following requirements:

  • The extension isn’t more than half the area of land around the original house
  • It isn’t higher than the highest part of the roof
  • Nor is it forward of the principal elevation or side elevation onto a highway
  • Single-story extensions mustn’t extend beyond the rear wall of the original house by more than eight metres for a detached house and more than six metres for any other property
  • The maximum height of your single-storey rear extension mustn’t be higher than four metres
  • Extensions of more than one storey don’t extend beyond the rear wall of the original house by more than three metres
  • Side extensions are single-storey with a maximum height of four metres and a width no more than half that of the original house
  • The extension doesn’t include verandas, balconies or raised platforms
  • The materials are similar in appearance to the existing house
  • Two-storey extensions are at most seven metres to the rear boundary.

Planning permission is generally required when you make significant changes to the building, such as structure and appearance or change the use of your building. In most cases, however, you should be fine without planning permission if you make extensions. It’s still probably worth contacting your local authority to see if the home extension ideas you have in mind need planning permission. 

Can I extend a new-build property? 

Most new-build homes don’t require an extension as they’ve recently been built and therefore are more or less complete. In rare cases where you’d like to extend a new build, it’s essential to check the warranty. In some cases, the warranty may become null and void if you decide upon a new build extension.

A home extension idea to make more of your home

Home extension ideas are a clever way of adding more space to your home while increasing its value. When done right, it adds another dimension to the property and gives it a new lease of life, whether it’s a kitchen extension, loft conversion or additional room in the home.

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Last Updated: October 20th, 2023