Have you been thinking about adding more space to your house in 2025 and searching for home extension prices? In this blog, we will break down the average home extension cost in 2025 by size and location so you can make an informed decision.ย
What is a Home Extension?ย
A home extension is when you add extra space to your existing house. This could mean adding a new room, building above your garage, extending out into the garden or going up into the loft.
There are lots of reasons why people choose to have a home extension including:ย
- A growing family so people need more bedrooms
- Creating an open plan kitchen and dining area
- Building a home office or studio
- Adding value to their home
Home extensions are often more cost effective than moving house.
If youโre looking to have a home extension built, at Consumer Advisory we will put you directly in touch with professional accredited contractors. Click on the following link to get up to 3 free quotes. Get Free Quotes
Types of Home Extensionsย
There are different types of home extensions, these are the most common ones:ย
1. Rear Extension
A rear extension is added to the back of your house this is usually leading out into the garden. This type of home extension is great for expanding your kitchen and creating a large dining area or adding a lounge.
2. Side Return Extension
If you have a narrow alleyway or unused side area next to your house, then a side return home extension can make the most of that space.
3. Wrap Around Extension
This combines a rear home extension with a side return home extension this forms an L shape. This type of extension gives you plenty of room and is popular for open plan living.
4. Double Storey Extension
If you need a lot more space, then a double storey extension can add rooms on both the ground and first floor. These types of home extensions are perfect for adding extra bedrooms and bathrooms.
5. Over Structure Extension
This type of home extension is built above an existing structure such as a garage. Itโs a good idea if you donโt want to take up any garden space.
6. Loft Conversion
This is technically not an extension outwards but upwards. Loft conversions are a great way to add an extra bedroom or office without changing the footprint of your home.
Why Do the Cost of Home Extension Vary?
All home extensions are unique and there are certain factors that will determine the overall cost of your home extension. This includes:ย
- Type and size – Single storey, double storey, kitchen or bathroom etc.
- Finish quality – Basic, mid-range, or luxury.
- Location – Labour, transport and materials in London cost more than in areas such as Kent, East Sussex or West Sussex.
- Complexity – Steel beams, foundations, planning or wall issues add costs.
- Additional fees – architects, structural engineers, planning permission, VAT and contingencies.
Standard Cost Ranges Around the Whole of the UK
This is the industry estimates in 2025 for home extensions:
- Single storey home extensions – ยฃ2,100 to ยฃ3,800 per mยฒ depending on quality
- Double storey home extensions – ยฃ1,950 to ยฃ3,550 per mยฒ; often 50-60% more total cost but cheaper per mยฒ than single storeyย
House Extension Prices by Regionย
Letโs have a look at the average prices of house extensions in 2025 by region.
London
- Single storey home extensions – ยฃ2,700 to ยฃ3,800/mยฒ, depending on finishย
- Double storey home extensions – add 50-60%, so ยฃ4,320 to ยฃ6,080/mยฒย
Surrey
- Single storey home extensions – ยฃ2,900 to ยฃ3,900/mยฒ, depending on finishย
- Double storey home extensions – add 50-60%, so ยฃ4,640 to ยฃ6,240/mยฒย
East Sussex
- Single storey home extensions – ยฃ1,400 to ยฃ2,400/mยฒ, depending on finishย
- Double storey home extensions – add 50-60%, so ยฃ2,240 to ยฃ3,840/mยฒย
West Sussex
- Single storey home extensions – ยฃ1,600 to ยฃ2,200/mยฒ, depending on finishย
- Double storey home extensions – add 50-60%, so ยฃ2,560 to ยฃ3,520/mยฒย
Kent
- Single storey home extensions – ยฃ2,200 to ยฃ2,800/mยฒ, depending on finishย
- Double storey home extensions – add 50-60%, so ยฃ3,520 to ยฃ4,480/mยฒย
How Long Does a Home Extension Take?
Here is a brief breakdown of how long an average home extension takes to build:
- Initial design and planning stage โ 4 to 8 weeksย
- Planning permission โ 8 to 12 weeksย
- Building control approval โ 1 to 2 weeksย
- Construction of a single storey home extension -10 to 16 weeksย
- Construction of a double storey home extension โ 12 to 20 weeks
- Final touches and any snagging โ 2 to 4 weeksย
How to Choose the Best House and Extension Builders?
Your choice of builder makes a huge difference to the result of extending your home. Here are some tips when searching for a professional:
- Check reviews and references – Look for builders with consistently good feedback.
- Ask to see past work – A reliable accredited contractor should have a portfolio.
- Get multiple quotes – Donโt settle for the first estimate, you should compare at least three.
- Make sure they’re accredited – Look for membership with trade bodies like FMB (Federation of Master Builders).
- Read the contract carefully โ Ensure the contract outlines payment terms, timeline and guarantees.
At Consumer Advisory Ltd we only work with reliable accredited contractors, so you can ensure you are receiving quality workmanship. We will put you directly in touch with house and extension builders who are qualified and work to legal safety standards. Click on the following link to get up to 3 free quotes. Get Free Quotes
Conclusionย
Itโs important to know the different types of home extensions and their average costs by region. If youโre looking to have a home extension built you need to hire a professional accredited contractor to ensure high quality of work and for safety and legal reasons. A house and extension contractor offers experience and knowledge and will build your home extension efficiently and to the highest standards. Consumer Advisory will put you directly in contact with approved and accredited contractors.ย
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