Garden Annexes
Garden Annexes, designed and built by GX Modular Ltd, offer a collection of highly insulated timber-framed living annexes, manufactured in Suffolk and installed on-site typically in 5 to 10 days. Their four pre-designed ranges combine precision engineering with customisable layouts to create comfortable homes in the garden.
Garden Annexes
Garden Annexes, designed and built by GX Modular Ltd, offer a collection of highly insulated timber-framed living annexes, manufactured in Suffolk and installed on-site typically in 5 to 10 days. Their four pre-designed ranges combine precision engineering with customisable layouts to create comfortable homes in the garden.
Garden Annexes
Garden Annexes, designed and built by GX Modular Ltd, offer a collection of highly insulated timber-framed living annexes, manufactured in Suffolk and installed on-site typically in 5 to 10 days. Their four pre-designed ranges combine precision engineering with customisable layouts to create comfortable homes in the garden.
Introducing Garden Annexes
Garden Annexes is the dedicated annexe brand of GX Modular Ltd, a Suffolk-based manufacturer specialising in self-contained timber-framed homes built with a blend of traditional craftsmanship and modern CAD/CAM precision. Their annexes are factory-prepared and delivered in sections for rapid on-site assembly by their in-house team, typically completed within 5 to 10 days. Designed for comfortable residential use, these highly insulated buildings are suitable for both close family use and broader accommodation needs.
Garden Annexes offer four annexe styles, each available in 24 sizes with numerous layout configurations. The Annexxa range is defined by its modernist European aesthetic and high-spec detailing. XB adds stainless steel and contemporary architectural touches. For those seeking more traditional styling, the dual-pitched St George and barn-inspired Ivyo ranges include tiled roofs and vaulted ceilings. All designs prioritise comfort, efficiency, and long-term durability.
Garden Annexes is also one of the few specialists with a dedicated show site, where you can explore annexes in different sizes and layouts. This gives you a clear feel for the quality, finishes, and design details across the range. Viewings are by appointment at their Suffolk site, with availability seven days a week.
Design
Garden Annexes offers four pre-designed ranges that can be tailored to suit the client’s needs. While each model has a fixed architectural identity and roofline, the interior layout, glazing configuration, finishes, kitchen and bathroom specification, and electrical positions are all highly customisable. Clients can choose from a variety of flooring, paint colours, and window placements, and work with the design team to create a layout that reflects how they want to live.
Layouts
Each annexe range is available in 24 sizes and can be partitioned into multiple rooms or left open-plan, depending on the client’s needs. Internal walls are built using v-grooved, fire-rated MDF panels, spray-finished in the factory. Options include open-plan living with zoned areas, defined bedrooms, storage rooms with internal or external access, and fully integrated bathrooms and kitchens. Mono-pitched ranges feature a decorative lattice ceiling with integrated lighting, while pitched roof models include vaulted ceilings with exposed trusses and optional gable-end glazing.
Approval Process
Garden Annexes designs its buildings to comply with the requirements of the Caravan Act, but can also handle Full Planning Permission if that is the route required for your project. Their experienced in-house team supports both approval paths and will advise on the most appropriate route based on how the annexe will be used and who will be living in it.
For Caravan Act projects, Garden Annexes regularly secures Lawful Development Certificates to confirm the building’s status as a mobile home, allowing it to be installed without Planning Permission in qualifying situations. Where Full Householder Planning Permission is necessary — such as for non-family use or commercial letting — they prepare and submit the planning application on your behalf. In both cases, the approval process is managed in-house as part of their full-service approach.
Service
Garden Annexes offers a complete turnkey service, handling all elements from initial design to final commissioning. Their Site Pack includes a detailed site survey, after which they provide a tailored quotation for the groundwork and mains service connections. This covers the concrete base, service trenches, and the installation of cabling and pipework for electricity, water, waste, and drainage. All of this work is undertaken by the Garden Annexes team as part of their overall service, avoiding the need for clients to coordinate with multiple contractors.
Kitchens and bathrooms are included as standard, fitted and tested by the in-house plumbing and electrical team, so the building is ready for occupation as soon as the installation is complete.
Structure
The buildings use a traditional multi-layer timber frame construction made from Glulam timbers, manufactured in-house using high-precision CAD/CAM machinery to achieve a 0.1mm component tolerance. The structure is insulated with 100mm PIR insulation in the floor, walls, and roof, and finished with specialist membranes, OSB sheathing, and a fire-rated wrap. Externally, MTX cladding is double spray-coated in the factory and colour-matched to doors, windows, and trims, requiring minimal maintenance. Roof finishes include Firestone EPDM rubber membranes or lightweight profiled roof tiles, depending on the model. All glazing units are 28mm Argon-filled double glazing, and each annexe includes electric heating for year-round comfort.
Site Challenges
Garden Annexes are experienced in working on complex garden plots, including sloping ground, narrow access, and sites near existing trees or with Tree Preservation Orders. During the site visit, they assess the terrain and discuss excavation or base-pivoting options to suit the conditions. Their installation team is equipped to manage bespoke groundwork as part of the Site Pack, ensuring a level and secure base even on challenging sites.