Extensions & Conversions
Take a look at our cost guides to see how much large building work like extensions and conversions will set you back so you can put together a realistic budget for your project.
Whether you’re looking to extend your kitchen with a side return extension or you want to convert your basement into a liveable space, read our cost guides to get an idea of how much each project costs before getting a more accurate quote from our database of reliable tradespeople.
Whether your extension or conversion is seen as budget or premium is mainly down to its size, but also the quality of the final fixtures and fittings. For example, a budget extension may include a single uPVC patio door that opens out into the garden, whereas a luxury extension quote may include full-width bifold doors.
Extensions and conversions can cost as little as £40,000 up to £150,000, but here are the average costs:
Budget extension cost
A basic, budget extension of around 20 square metres will cost an average of £45,000. This figure includes basic electrical and plumbing work, basic painting and decorating and flooring such as vinyl or laminate.
Mid-range extension cost
If you’re looking for a slightly larger extension with a higher standard of finish, for example with recessed downlights or wooden flooring, expect to pay a bit more. A mid-range extension of around 30 square metres will cost an average of £72,000.
Luxury extension cost
A luxury extension with premium, high-end fittings such as aluminium windows, engineered wood flooring and underfloor heating will cost an average of £92,000, but you could pay as much as £150,000 depending on the finishes you choose. The sky really is the limit when it comes to premium fittings and finishes for your extension, so it’s important to set a realistic budget to keep your spending under control.
