New research has revealed one property feature that could significantly boost a property’s value by up to £165,000. Properties equipped with this sought-after addition command an average premium of 20.7 per cent – equivalent to £129,300 more than comparable properties without it, rising to over £167,000 depending on where the property is located, making it an appealing upgrade for property investors, developers and landlords to consider.
The analysis of market listings across England has revealed that properties with an annexe consistently outperform their counterparts. The uplift is particularly notable in Yorkshire and the Humber, where sellers can expect a 24.3 per cent premium, adding £110,500 to their property’s value. Similarly, properties in the West Midlands and North East with annexes also see a 23.9 per cent uplift, equating to additional values of £135,095 and £101,252, respectively.
The South East leads in absolute value gains, with properties achieving a £167,500 premium, representing a 21.4 per cent price uplift. Even in London, where property prices are already among the highest, the feature commands a 10.3 per cent premium, adding £107,550 to property values.
Adam Day, Head of eXp UK, which conducted the research, explains: “An annexe provides the perfect compromise, allowing family to stay, but within their own separate part of the house. It’s no surprise that an annexed property commands a pretty penny more, and those looking to sell can expect to do so for around 21% more versus comparable properties without.”
Whether attached to the main property or detached, an annexe provides flexibility, appealing to buyers seeking multi-generational living options, rental income potential or additional private space. The cost of building an annexe in the UK depends on factors such as size, materials and location. However, transforming existing spaces, such as garages or lofts, into annexes can be more economical. Some annexes are fully self-contained with kitchens and bathrooms, while others may lack these amenities. Notably, omitting certain facilities can influence council tax assessments. For instance, an annexe without a kitchen might not be classified as a separate dwelling for council tax purposes.
This insight offers a clear message: in a competitive market, the right property upgrades can significantly boost return on investment, making annexes a feature worth serious contemplation while also considering the associated construction costs and council tax implications.
