Many single-storey rear extensions fall under permitted development, but there are strict limits on size, height and location. Larger or two-storey extensions usually require full planning permission. Always check with your local council.

Even if planning permission isn’t needed, building regulations approval is almost always required. These cover structural integrity, fire safety, insulation, drainage and energy efficiency.

In most cases, a well-designed extension can increase your property’s value by adding extra living space and improving functionality. However, the amount of added value depends on factors such as location, quality of the build and whether the extension compliments your home’s style. It’s also worth checking local property price ceilings to ensure your investment makes financial sense. Consulting an estate agent before starting can give you a realistic idea of potential returns.

For most extensions, yes – especially if you’re altering load-bearing walls or adding multiple storeys.