Are you running out of space in your home but not ready to move? A house extension might be the perfect solution to get the room you need without the hassle of moving. Whether you're adding an extra bedroom, expanding your kitchen house extensions can add significant value to your home. But how much does it actually cost to extend your house in the UK?
Here are a few reasons why homeowners choose to extend their homes:
The cost of a house extension in the UK can vary widely depending on a number of factors. The average cost is between £1,500 to £2,500 per square meter for a basic single-storey extension. However, this price can increase depending on the complexity and location of the build.
| Extension Type | Cost Range (per square metre) |
|---|---|
| Single Storey | £1,500 - £2,500 |
| Two Storey | £1,700 - £2,500 |
| Basement Extension | £3,000 - £4,000 |
| Loft Conversion | £1,800 - £3,000 |
| Conservatory | £10,000 - £25,000 (for entire project) |
Note: These costs do not include VAT, which adds 20% to the final bill.
There are many variables that can affect the final cost of a house extension. Here are some key factors to consider:
The larger the extension, the more expensive it will be. For instance, a simple 20m² extension could cost between £40,000 - £60,000, while a larger 50m² extension might set you back £100,000 or more.
The cost of labor and materials varies greatly depending on where you live. House extensions in London and the Southeast of the UK tend to be more expensive compared to other parts of the country.
Different types of extensions come with different price tags. For example, a loft conversion is generally less expensive than a basement extension because of the excavation work required.
The materials you choose will significantly impact the cost. High-end finishes, bespoke windows, or a luxury kitchen will increase the overall price of your extension.
Before you start building, you’ll need to get planning permission and hire an architect or designer. These costs can vary from £3,000 to £7,000 depending on the complexity of the design.
Building a house extension doesn’t have to break the bank. Here are some tips to help you save on costs:
If you have the skills, consider doing some of the work yourself, such as painting or demolition. Just be sure to leave the more complex jobs to professionals.
Custom materials can quickly drive up the cost. Opt for standard sizes and materials for windows, doors, and fittings to reduce expenses.
The simpler the design, the cheaper it will be to build. Straightforward, square or rectangular shapes will always be more cost-effective than complex structures with curves or odd angles.
If you're confident in managing contractors, you can act as the project manager. This can save you 10-15% of the overall cost but will require a lot of time and organization.
To get a rough idea of how much your extension will cost, you can use a house extension calculator. Here's how it works:
For example, a 30m² extension at £2,000/m² would cost around £60,000 before VAT. With VAT, the total would be £72,000.
While the costs can vary, understanding the factors that influence the price and making smart choices along the way will ensure your project stays on budget.
Not always. Many extensions fall under 'Permitted Development Rights', meaning you don't need planning permission. However, there are limits to size and location. It's always best to check with your local planning authority before starting work.
The duration can vary, but on average:
These timelines can change based on the complexity of the project and any unexpected issues.
In most cases, yes. A well-designed extension can add 10-20% to your home's value. However, it's important not to over-develop your property beyond what's typical for your area, as this might limit the return on your investment.
Usually, yes, but it can be disruptive. Discuss this with your builder beforehand. You might need to temporarily relocate for certain stages of the work, especially if you're extending your kitchen or bathroom.
It's wise to set aside 10-20% of your total budget for unexpected expenses. This contingency fund can cover unforeseen issues like structural problems or changes to your plans.
While not always necessary, an architect can be valuable for complex projects. They can help with designs, planning applications, and project management. For simpler extensions, you might only need a good builder or a design-and-build company.
Consider these options:
Possibly. Adding value to your home might move it into a higher council tax band, but this usually only happens when the property is sold. It's worth checking with your local council for specific rules in your area.
If you're skilled in DIY, you might be able to handle some aspects like decorating or basic carpentry. However, leave structural work, electrics, and plumbing to the professionals. DIY mistakes can be costly and potentially dangerous.
Look for these qualities:
A quote is a fixed price that the builder agrees to stick to, barring any agreed changes. An estimate is a rough guide that might change. Always try to get a detailed, fixed quote before work begins.
Yes, but you'll need permission from the freeholder. Check your lease agreement and consult with your freeholder early in the planning process.
