When considering a 2 storey extension for your home in 2024, figuring out the cost must be a top priority for you. Because you’re making a major investment in your property, all money aspects of it must be thoroughly covered.
The cost of 2 storey extension UK can vary based on factors like size, materials, and design complexity. With the right information, you can make informed decisions and move forward without unexpected house extension costs. So keep reading and know these important numbers before proceeding.
Average Cost of 2-Storey Extension UK
The amount you pay to get more space will be influenced by the house extension ideas you’ve shortlisted. Because if you like bespoke interiors and fittings, the cost of 2 storey extension will be massive—and vice versa.
But on average, here’s what you’ll likely pay to get two more storeys in the house:
Average Cost of a 2-Storey Extension in the UK in 2024
In 2024, the financial landscape for constructing a two-storey extension in the UK presents a range of costs that potential homeowners need to consider. Understanding these costs is crucial for planning and executing your home extension without encountering financial surprises along the way.
For a typical two-storey extension, the average cost per square meter ranges between £1,800 and £2,800. To provide a clearer perspective, let’s explore the estimated total costs based on two common extension sizes:
● 40 Square Metre Extension (20 sqm per floor)
The cost for a 40 sqm extension varies from £72,000 at the lower end to £112,000 at the higher end. This size is great if you want to add a couple of rooms—like a new bedroom upstairs and a larger living area or kitchen on the ground floor. For instance, if you go for mid-range finishes and standard construction materials, the cost will be closer to the middle of this range.
● 60 Square Metre Extension (30 sqm per floor)
A larger 3 meter house extension covering 60 sqm will cost between £108,000 and £168,000. This size allows for more extensive additions, such as an additional bathroom and a spacious master bedroom on the new upper floor, alongside an expanded family room or kitchen below. Opting for high-end finishes and custom features will push your budget towards the upper limit.
Also, when planning your budget for the 2 storey extension, remember that some costs might not be immediately obvious. These can include planning permissions, architectural design fees, and landscaping changes that happen post-construction. That’s why it’s smart to set aside a contingency fund of around 10-15% of the total project cost to cover unexpected expenses so your project isn’t halted by unforeseen financial hurdles.
Detailed Cost Breakdown of a 2 Storey House Extension in the UK
The house extension London cost will depend on how simple or fancy you go with the project. Or if you want a single storey extension right now will opt for another one later. But some of it stands solid, regardless of the extension scale.
Here’s a detailed breakdown of house extension cost you must remember:
Please note, these costs are not fixed and may vary depending on project specifics. They’re provided here to give you a general idea of what to expect.
| House Extension Component | Cost Range |
| Architect Fees | £3,600 – £10,000 |
| Structural Engineer | £1,000 – £2,000 |
| Groundworks and Foundations | £5,000 – £10,000 |
| Brickwork and Structure | £25,000 – £40,000 |
| Roofing | £6,000 – £12,000 |
| Windows and Doors | £4,000 – £8,000 |
| Electrical and Plumbing | £5,000 – £15,000 |
| Plastering and Decorating | £3,000 – £6,000 |
| Flooring | £2,000 – £5,000 |
| Kitchen Installation (if needed) | £8,000 – £20,000 |
| Bathroom Installation (per bathroom) | £4,000 – £10,000 |
| Waste Removal | £500 – £1,500 |
| Landscaping | £2,000 – £5,000 |
Make Your 2 Storey Extension Go Well With the Help of Expert Contractors
Executing a two-storey extension can seem like a tough task, but with the help of the right contractors, it doesn’t have to be. Experienced professionals at Chaboun Construction will guide you through every step, from initial cost estimates to the final touches, so your project stays on budget and on schedule. We’ll handle the complexities of design and construction so you get to focus on the exciting parts—like enjoying your new space. Choose expert contractors at Chaboun and let’s bring your home extension dream to life.
Benefits of a Double Storey Extension
- Space That Grows with Your Family A double storey extension adds substantial living space by building up instead of just out. You get twice the extra room compared to a single-storey addition, making it perfect for growing families. The upper floor can house new bedrooms and bathrooms, while the ground floor might become a larger kitchen, living room, or home office.
- Better Use of Your Land Building upward is a smart way to use your property. Unlike single-storey extensions that take up more garden space, double storey extensions leave more of your outdoor area free. This means you keep more of your yard for gardening, children’s play areas, or outdoor entertaining.
- Boost Your Home’s Value Adding a double storey extension often increases your property’s value significantly. The extra bedrooms and living spaces make your home more attractive to future buyers. Many families look for homes with more rooms, so this investment can pay off when you decide to sell.
- Save Money in the Long Run While a double storey extension costs more upfront than a single storey, it’s usually more cost-effective per square foot. You’ll only need one foundation and one roof for twice the space. Plus, you won’t need to move to a bigger house, saving you money on moving costs, stamp duty, and legal fees.
- Keep Your Home’s Look Balanced Double storey extensions often look more natural and balanced than single-storey additions. They blend better with your existing house design and don’t stick out as much. This helps maintain your home’s overall appearance and street appeal.
- Less Disruption During Building Building up means workers focus on one area of your property instead of spreading across your yard. While construction takes longer than a single storey, the overall impact on your garden and outdoor space is usually smaller. You’ll also only need to set up scaffolding and building equipment in one spot.
Double vs Single Storey Extensions: Which is Right for Your Home?
| Aspect | Double Storey Extension | Single Storey Extension |
| Cost Differences | Costs 50-75% more than a single storey but provides more space for the money. | Cheaper to start with, but offers less added living area for the price. |
| Space and Layout | Adds space on two floors, ideal for bedrooms upstairs and living areas downstairs. | Expands only the ground floor, suitable for larger kitchens or open-plan areas, not extra bedrooms. |
| Garden Space | Builds upward, conserving garden space for outdoor activities. | Spreads outward, using more garden space, which may impact smaller yards. |
| Planning Permission | Often requires stricter planning approval due to height and impact on neighbors. | More likely to fall under permitted development rights with fewer restrictions. |
| Build Time and Disruption | Typically takes 4-6 months, with work focused in one area of the property. | Generally takes 3-4 months, but may extend across more of the yard, causing more disruption. |
| Light and Ventilation | May affect light in existing rooms; windows on two levels allow for better airflow between floors. | Can include skylights and roof lanterns to increase natural light. |
| Resale Value | Often adds more value due to additional space and potential for extra bedrooms. | Enhances living space but may not increase resale value as much without extra rooms buyers desire. |
7 Most Popular Double Storey Extension Designs for Your Home
- Traditional Double Extension This classic design matches your existing house style perfectly. It uses similar bricks, windows, and roof tiles to create a seamless look. The extension feels like it was always part of your home, with matching features both upstairs and downstairs.
- Modern Glass Extension Glass plays a big role in this striking design. Large windows and glass walls bring in lots of natural light. The style often includes sleek metal frames and modern materials, creating a bright, contemporary feel that can contrast nicely with older homes.
- Kitchen-Master Suite Combo This popular layout puts a large kitchen-diner downstairs with a master bedroom and bathroom above. It’s perfect for families who want more social space and a private retreat upstairs. The design often includes French doors or sliding doors that open to the garden.
- Terraced House Extension Made specially for terraced homes, this design works within narrow spaces. It usually extends into the back garden, adding a kitchen or dining room below and a bedroom or bathroom above. Smart window placement helps bring in light without overlooking neighbors.
- L-Shaped Design By wrapping around a corner of your house, this design creates lots of space. Downstairs might include an open-plan living area, while upstairs adds bedrooms or a home office. It’s great for creating a natural flow between old and new spaces.
- Split-Level Extension Perfect for sloping gardens, this design uses different floor levels creatively. It might step down from your existing house, creating interesting spaces and making the most of views. The split levels add character and make each room feel unique.
- Gable-End Extension This design features a pointed roof that matches traditional house styles. The high ceiling space upstairs can include skylights or tall windows, making rooms feel bright and spacious. It works well for both period and modern homes.
FAQs
How much does a second storey extension cost UK?
The cost of adding a second storey extension in the UK ranges from £1,800 to £2,800 per square meter. This cost of 2 storey extension UK translates into total project costs of £72,000 to £112,000 for a 40 square meter extension and £108,000 to £168,000 for a 60 square meter extension.
How much value does a 2 storey extension add?
A two-storey extension can notably increase your home’s value, which often exceeds the initial investment made into the project. The added value depends on several factors, like the quality of construction, the design, and the market conditions. Generally, a well-designed and executed extension can boost your property’s market value by 10-20%, sometimes even more, especially in high-demand areas.
Is a double storey extension worth it?
Deciding whether a double storey extension is worth it depends on your situation. For many homeowners, the benefits of increased living space, possible rental income from more rooms, and increased property value outweigh the costs of construction. If your family is growing or you want to add substantial living space without moving, a double storey extension can be worth it.
Do you need planning permission for a 2 storey extension?
In most cases, you will need planning permission for a two-storey extension if it alters the footprint of your existing home. If you’re unsure what rules you’ll have to follow, consult with your local planning authority early in the project planning stage to ensure compliance and smooth progression of your extension project.
