How much does a house extension cost in Solihull? (2026 guide)
A house extension is one of the biggest investments most homeowners will make in their property, so it is completely understandable to want a clear idea of the cost before you begin. In this guide we set out realistic price ranges for extensions in Solihull and the wider West Midlands, explain what drives the cost up or down, and share practical advice on keeping your project on budget. All of the figures below are indicative ranges based on typical projects, and the only way to get a genuinely accurate price is a site visit and a detailed quote.
Typical house extension costs
Extension costs vary a great deal from project to project, but the ranges below give a realistic starting point for budgeting. They assume a good quality finish and include the building work, though not always fixtures such as kitchens, which are covered separately.
| Project | Indicative cost |
|---|---|
| Single storey rear extension | £30,000 to £70,000 |
| Double storey extension | £55,000 to £120,000 |
| Wrap around extension | £60,000 to £130,000 |
| Side return extension | £35,000 to £75,000 |
| Typical build rate | £1,800 to £3,000 per m² |
Figures are indicative UK ranges to help you budget and are not a quote. Actual costs depend on size, specification and site conditions.
What affects the price of an extension
Two extensions of exactly the same size can cost very different amounts, and understanding why helps you plan sensibly. The biggest factors are:
- Size and shape. Larger extensions cost more overall, but the price per square metre often falls as the project grows, because fixed costs such as scaffolding are spread further.
- Specification and finish. Underfloor heating, high end flooring, bespoke joinery and premium glazing all add cost. A simple, well built extension can be very good value.
- Glazing. Bi fold doors, large roof lights and full height glass are popular but expensive. They transform a space but can add several thousand pounds.
- Kitchens and bathrooms. If your extension houses a new kitchen or bathroom, the fittings and appliances are a significant part of the budget and are usually quoted separately.
- Structural work. Steel beams, underpinning and removing load bearing walls to create open plan space all add to the cost.
- Access, drainage and ground conditions. Difficult rear access, moving drains or poor ground can increase the groundworks element of the project.
Single storey or double storey?
If you are weighing up your options, it is worth knowing that a double storey extension is often better value per square metre, because the foundations and roof serve two floors rather than one. A single storey extension, on the other hand, is usually quicker and less disruptive. We cover this in detail in our guide to single storey versus double storey extensions, which is worth a read if you are still deciding.
Do not forget the extra costs
The build itself is the largest cost, but there are others to budget for. These can include architectural drawings, structural engineer calculations, a planning application fee if one is needed, building control fees, and party wall agreements where your extension is close to a neighbour. A good builder will explain all of these to you up front so there are no surprises. It is also sensible to keep a contingency of around ten per cent for the unexpected, particularly with older properties.
Planning permission and building regulations
Many single storey extensions fall under permitted development and do not need a full planning application, which can save both time and money. Almost all extensions, however, need building regulations approval. We explain the difference clearly in our guide on whether you need planning permission, and we handle the whole process for you as part of our house extensions service.
How to keep control of your budget
The single most useful thing you can do is insist on a clear, itemised quote before any work begins, so you can see exactly where the money is going and make informed choices about the specification. We also recommend agreeing a written schedule and a payment plan tied to stages of the build, which keeps everyone accountable and avoids surprises later. Choosing an established, properly accredited builder is just as important as the price itself, and our guide on how to choose a builder in Solihull sets out the checks worth making.
See real examples and get a quote
You can view examples of completed work on our case studies page, and if you are ready to talk figures for your own home, we offer a free, no obligation site visit and quote across Solihull, Shirley, Knowle, Dorridge and the wider West Midlands. The ranges above are a guide only, but a short conversation will give you a much clearer picture.
Call 07393 194 336Get a free quote