Garden Living Annexes Less Than 25sqm in Size
Updated: 1 December 2025
On this page, we are featuring garden annexe projects that are less than 25 square meters in size. As you scroll through, you’ll see that although these annexes are classed as small buildings, each one is a fully functional, well-designed, and well-specified living space. These projects, completed by a range of companies, showcase how talented designers can maximise every square metre, whether the annexe is used for guest accommodation, independent living, or as a multifunctional space.
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Each project has been tailored to meet the owner’s specific requirements and the available space in their garden. Some serve as guest bedrooms with en-suite facilities, offering flexibility for when friends or family visit, while others are compact living annexes, allowing a relative to live independently but close to the main house.
These garden annexe buildings have been designed to comply with either Full Planning Permission and Building Control regulations for permanent residences, or the rules of the Caravan Act, ensuring their legal status as mobile homes.
We hope these projects inspire you and give you an idea of the different spaces that can be created within this footprint range. The annexe projects are listed by size, from smallest to largest. If you're interested in exploring larger annexes or different room configurations, feel free to check out our case studies on one-bedroom, two-bedroom, and open-plan studio annexes.
This 16.5 sqm boutique garden bedroom with an ensuite, designed by Timeless Garden Rooms, highlights the versatility of garden annexes. Measuring 3m by 5.5m, it includes a comfortable double bedroom, ensuite shower room, and a covered porch—perfect for removing muddy shoes. The clients had clear design ideas, and Timeless Garden Rooms worked closely with them to refine the layout, delivering a high-spec finish reminiscent of a boutique hotel. Externally, soft green cladding pairs beautifully with a Cedar shingle roof, while inside, a feature panelled wall enhances the room's stylish aesthetic. Built on the Isle of Wight, the project complies with Building Regulations, making it an ideal guest accommodation solution.
This 19.84 sqm granny annexe by Ark Design Build demonstrates how small gardens can still accommodate fully functional living spaces. Measuring 3.2m by 6.2m, this contemporary annexe in Esher was designed for the client’s mother to stay in during extended visits. Despite its modest size, the building includes a spacious main room with a mono-pitched roof, a large roof window, and sliding doors that flood the space with natural light. It also features an ensuite shower room and a kitchenette, making it a fully self-contained unit. Ark Design Build oversaw every aspect of the project, from Planning Permission to Building Control sign-off, ensuring a smooth, hassle-free build.
This 20.65 sqm ensuite garden bedroom, designed by Executive Garden Rooms, provides a practical and stylish guest accommodation solution. Measuring 5.9m by 3.5m, the building features a double bedroom with a cosy living area and an adjacent shower room, creating a self-contained annexe. The exterior, clad in low-maintenance Cedral fibre cement boards in a soft green-grey, is paired with anthracite grey uPVC frames. Executive Garden Rooms managed the project from start to finish, including groundworks and compliance with Planning Permission and Building Regulations, ensuring a seamless experience for the client.
This 21 sqm student den by Timeless Garden Rooms showcases how adaptable their buildings can be, offering younger family members a private space for study and relaxation. Part of their modern Studio Range, the mono-pitched structure is clad in feather-edge Larch and features sliding doors along with additional windows for enhanced natural light. Inside, partition walls create two separate living spaces and a shower room. Timeless Garden Rooms handled the entire process, from groundworks to final decoration, delivering a contemporary, comfortable space for the client’s university student son.
This 21.5 sqm granny annexe by Executive Garden Rooms is a compact yet functional living space, designed for comfortable one-person living. The open-plan layout includes a combined bedroom and lounge area, with a kitchenette and a shower room. The project required Full Planning Permission and Building Control approval, both managed by Executive Garden Rooms as part of their turnkey service. The exterior is clad in low-maintenance Cedral weatherboard, while the interior features plastered walls, wood flooring, and a well-equipped kitchenette. Despite its compact size, the annexe offers all the essentials for independent living within a small garden space.
This 21.6 sqm en-suite garden bedroom, designed by Executive Garden Rooms, provides a comfortable and stylish guest space for a family in Dorset. The building, measuring 6m by 3.6m, features a double bed, sofa bed, and storage, with floor-to-ceiling windows and French doors allowing natural light to flood the room. A sleek, fully equipped shower room with porcelain-tiled flooring completes the design. Finished with white walls, laminate wooden flooring, and bespoke wrap-around glazing, the space feels open and modern. Executive Garden Rooms handled the entire project, including planning approval and utility connections, ensuring a turnkey solution for the client.
This 21.76 sqm ensuite garden bedroom, designed by Annexe Spaces, provides a smart alternative for homeowners unable to pursue traditional house extensions. After a rejected planning application for their house extension, the client opted for a sleek garden annexe finished with crisp white Silicon K-Render on three sides, complemented by dark grey doors, windows, and composite decking. Inside, the main room provides space for a bed and seating, while the fully tiled shower room features modern fixtures and a generous shower. Oak-effect laminate flooring, plastered walls, and LED lighting throughout create a high-quality, modern finish, ideal for extra living space.
This 24 sqm one-person granny annexe, designed by Executive Garden Rooms, is a compact yet fully functional living space for independent living. Built for the client’s father, the annexe features a combined living and sleeping area, a kitchen with space for a washing machine, and a well-appointed shower room. Cat6 cabling for fast internet, plentiful power sockets, and LED downlights ensure modern conveniences, while a sedum roof enhances insulation and helps the building blend into its surroundings. Executive Garden Rooms managed every aspect, from Planning Permission and Building Control approval to groundworks, ensuring a seamless build.