Whether you’re creating a home for an elderly relative or planning for the future, discover the benefits of granny annexes, along with expert advice on planning, costs, and design.
Complete home/living solution 
Price includes kitchen and bathroom 
Complies with building regulations 
At The Green Room, we design and build bespoke granny annexes for families across the UK. From planning applications and groundworks to utility connections and interior finishes, we manage every stage of the project. Our annexes are warm, energy-efficient, and built to the highest standards, creating comfortable homes that are ready to enjoy from day one.
Fully plastered internally
Flooring
Screwpile or reinforced concrete pad foundations.
Supply of all services for bathroom and kitchen facilities.
Trenching for drainage and make good including re-instating paving where necessary.
We design and build each granny annexe to the same standards you’d expect from a traditional home. Whether you choose a one-bedroom, two-bedroom or even a three-bedroom annexe design, you’ll enjoy a layout that works perfectly for everyday living.
Every garden annexe includes a fitted kitchen, en-suite shower room, heating, and built-in storage, all tailored to your needs. See the many options we offer on our kitchen, bathroom and furniture page.
We manufacture our granny annexes for comfortable, long-term use, combining highly insulated SIPs construction with engineered foundations and durable internal and external finishes.
Every annexe also comes with our 10-year comprehensive guarantee for added peace of mind.
A wide choice of custom options is available, including internal walls, doors, canopies, bathrooms, kitchens, fitted furniture and sliding doors. Everything can be tailored to suit your space and how you plan to use it.
Our space-saving kitchens include a sink, dual hob, extractor fan and fridge with freezer compartment. As a result, they’re ideal for smaller annexes where every inch of space counts.
For a neat finish, choose a hideaway kitchen that folds away when not in use. A practical choice that keeps your living area open and flexible.
We offer a wide range of kitchen styles, all finished in high-quality materials with modern appliances and clever storage options.
Each granny annexe includes a private bathroom with a walk-in shower, toilet and sink. Designed for comfort, safety and ease of use.
Built-in wardrobes with sliding doors, shelves and drawers come as standard. Perfect for keeping your annexe organised and clutter-free.
A combined toilet and sink in an L-shaped unit provides a neat, practical solution while maximising space without sacrificing style or storage.
Our en-suites feature chrome electric showers with thermostatic controls and built-in safety stop features for added peace of mind. As a result, they deliver safe and reliable showering for the whole family.
What’s more, these showers are designed with accessibility in mind, making them suitable for those with limited sight, hearing or dexterity, and have received the RNIB Approved Gold Award.
Ecostrad iQ Ceramic radiators provide efficient, controllable heating throughout the annexe, with built-in Wi-Fi, motion sensing and app-based energy monitoring for added convenience.
Our 12mm laminate flooring features Hydroseal technology for added water resistance and durability, making it a practical, low-maintenance choice for everyday annexe living.
Smooth plastered walls and ceilings create a traditional residential finish rather than the panelled interior often associated with garden buildings.
LED downlights are fitted throughout the annexe, with external sensor lighting at the entrance for added safety and convenience. Our low-profile downlights are fire-rated and available in a choice of colour temperatures.
These practical additions offer extra shelter at the entrance or along one side of your annexe. Ideal for keeping the area dry, shaded and usable in all weather.
Sliding doors are a smart, space-saving option that allow for smooth and easy access between rooms or built-in storage areas. As a result, they’re ideal for smaller layouts where making the most of the available space is important.
Most garden annexe companies stick to 2.1m ceilings. By comparison, ours are 2.3m as standard, creating a taller, brighter and more comfortable living space. In addition, the pitched-roof design and internal vaulted ceiling enhance the sense of space, creating a bright, open and airy feel throughout the lodge.
Our pitched roof option includes TapcoSlate tiles and a vaulted ceiling inside. It brings extra headroom and a more open feel throughout the space.
Whether you need space for one person or more, we offer a range of layouts and sizes to suit your garden and living needs. In addition, all of our garden annexes are fully customisable and built to match your preferred design.
A compact and comfortable granny annexe with an open-plan living area, fitted kitchen, separate bedroom, and walk-in shower room. As a result, it provides an ideal solution for independent living without taking up too much garden space.
Designed for families who need extra garden accommodation, this layout includes two bedrooms, a larger kitchen and living space, plus a walk-in shower room. In addition, it offers a practical and comfortable solution for couples or live-in carers.
Our three-bedroom granny annexe includes two double bedrooms, a single room that can also serve as a study, an open-plan living area, a fitted kitchen, and a walk-in shower room. As a result, it offers a practical and comfortable solution for families who need more space.
We build every granny annexe using 172mm Structural Insulated Panels (SIPs) to create a strong, highly insulated, and energy-efficient home that lasts for years. This modern construction method also speeds up the installation process, reducing disruption at your property. You can also read our guide to granny annexe construction methods, where we compare SIPs with timber frame and traditional brick and block construction.
Find out more about granny annexe construction methods, including how SIPs compare with timber frame and traditional brick and block construction.
Depending on the size of your annexe, our team typically completes the installation within 3 to 6 weeks, so you can start enjoying your new living space sooner.
SIPs panels provide excellent thermal performance, helping to keep your annexe warm in winter and cool in summer. As a result, energy use is reduced and running costs stay low throughout the year.
Find out more about granny annexe insulation and U-values, including how the floor, walls and roof affect thermal performance.
We use a mix of fibre cement and wood-grain effect composite cladding that is low maintenance and built to last. Fascias, soffits and trims are made from durable steel, aluminium or PVC.
Every granny annexe includes strong, secure PVCu windows and doors with 28mm argon-filled sealed units that meet A-rated energy standards. As a result, your annexe stays warm, energy-efficient, and comfortable throughout the year.
Our standard flat roof is finished with a seamless RubberCover EPDM membrane, providing long-lasting protection against the elements. A decorative gravel topcoat enhances durability while creating an attractive, low-maintenance finish.
If you prefer a more traditional appearance, we also offer a pitched roof option finished with premium TapcoSlate tiles. Inside, the pitched roof creates a vaulted ceiling, making the living space feel brighter, more spacious, and airy while adding character and style to your annexe.
Every garden annexe is built on either engineered screw piles or reinforced concrete pad foundations, depending on your site’s ground conditions and the structural requirements of the building. This provides a strong, stable foundation designed to support your annexe for many years while meeting Building Regulations requirements.
For complete peace of mind, we supply full construction drawings, structural calculations, and foundation load calculations as standard. This ensures every annexe is professionally engineered and fully documented before installation begins.
When you choose a granny annexe from The Green Room, your quotation includes the essential elements needed to create a complete, comfortable home. From foundations and utility connections to the kitchen, bathroom and internal finishes, we manage the project from start to finish.
Your annexe is fully insulated and built for comfortable year-round living. We provide a detailed, fixed-price quotation so you know exactly what’s included before work begins.
See our granny annexe process to find out how we take your project from the initial site survey and bespoke design through to planning, installation and final handover.
Internal painting and decorating are not included, as the newly plastered walls and ceilings need time to dry fully before decoration.
Granny annexe prices start from £85,000, including VAT where applicable, depending on the size, layout and specification. For a detailed breakdown of what’s included and the factors that can affect the final price, see our guide to garden annexe costs.
Browse our collection of completed granny annexes and garden lodges to see a range of layouts, sizes and finishes we’ve created for our customers. Every project is designed around the available space and the individual needs of the people who will live there.
Browse our Granny Annexe Gallery to explore completed one, two and three-bedroom annexes in a range of layouts, styles and finishes.
Watch our completed granny annexe videos to see the space, finish and build quality of our projects in more detail.
Granny Annexe - Installed near Peterborough
Granny Annexe - Installed near Corby, Northamptonshire
Granny Annexe - Installed in Barwell, Leicestershire
Granny Annexe - Installed in Bath, Somerset
Every family is different, and so is every granny annexe we build. That’s why our case studies show how we’ve helped customers create safe, comfortable garden accommodation for their loved ones, right at the bottom of the garden. In addition, each project highlights the flexibility and practicality of our bespoke designs. Take a look at some of our recent projects to see what’s possible.
The Burlington Lodge - Three Bedroom Garden Lodge
The Woodside XL Lodge – Two Bedroom Garden Lodge
The Carlton Lodge - One Bedroom Garden Annexe
Two Bedroom Garden Annexe in Maidstone, Kent
One Bedroom Granny Annexe in Luton
One Bedroom Annexe in Desborough
Every project starts with understanding your garden, requirements and how you want the space to work. Following your site survey, we’ll create a bespoke design and detailed, fixed-price quotation tailored to your project.
Request a free site survey to start planning your granny annexe.
We’ll first email you a selection of granny annexe plans with example layouts, specifications and guide prices. If you’d like to explore your project further, we’ll arrange a free, no-obligation site survey to assess the available space, access, ground conditions and utility connections.
Following the survey, we’ll prepare your bespoke design and detailed, fixed-price quotation. If you decide to proceed, we’ll manage the planning, groundworks, installation and internal fit-out through to final handover. You can see each stage in more detail on our granny annexe process page.
A granny annexe is a self-contained home built in your garden. It usually includes a bedroom, bathroom, kitchen and living space, allowing a relative to live close by while keeping their independence.
The best granny annexe is one that meets your family’s needs, fits your available space and is built to a high standard. Look for a company that offers bespoke designs, energy-efficient construction, transparent pricing and a comprehensive installation service. It’s also worth considering the quality of materials, warranty, customer reviews and aftercare support rather than focusing solely on the lowest price.
Read our guide to what makes the best granny annexe for a closer look at the construction, insulation, design, pricing, guarantees and aftercare worth comparing.
The key differences come down to size and the type of Local Authority approval required.
In short: Every Garden Lodge stays within Caravan Act size limits. A Granny Annexe can too, but it has the flexibility to go bigger if you need the extra space — you’ll just need full planning permission in that case.
Yes. Our granny annexes use Structural Insulated Panels (SIPs) in the floor, walls and roof to provide high levels of insulation for comfortable year-round living. Rather than relying on general claims about insulation, we calculate the U-values of the main building elements. Read our guide to granny annexe insulation and U-values to learn more.
Instead of maintaining a costly showroom, we’ve chosen a more efficient approach that keeps our prices competitive. The cost of running a showroom ultimately has to be passed on to customers, and we’d rather you invest your budget in your garden annexe than in our overheads.
Yes. Every granny annexe includes a kitchen and bathroom as standard. For garden rooms, we can add a toilet, shower, or kitchenette depending on your needs. Everything is fully fitted and connected by our qualified team.
Our fully fitted one-bedroom granny annexes start from £85,000, including VAT where applicable. The final cost depends on the size, layout, specification and site requirements. See our garden annexe cost guide for a detailed breakdown of what’s included.
For an annexe, you will typically need to apply for either Full Planning Permission or a Lawful Development Certificate (LDC) from your Local Planning Authority (LPA). We handle this process on your behalf.
Whichever route you take, our team handles the paperwork and contacts the local authority on your behalf. For further information, please see our planning page.
Most builds take between 4 to 6 weeks, depending on size and design. We manage the full project from groundwork to final fittings, so everything runs smoothly and on schedule.
Yes. Every garden annexe we build is made to order. You choose the floor plan, kitchen units, bathroom fittings, exterior cladding and more. We’ll help you design it to suit your space and needs.
Our quotations include the essential elements required for your completed annexe, including foundations, service trenching, electrics, heating, flooring, kitchen and bathroom installation and internal plastering. Internal painting and decorating are not included because the new plaster needs time to dry before decoration.
Yes. While often built for elderly relatives, granny annexes are also ideal for adult children, guests, or anyone needing independent space.
Some granny annexes are designed to meet the legal definition of a caravan under the Caravan Act, which means they can be relocated if necessary. However, moving an annexe is a specialist operation that usually requires professional lifting equipment and transport. In practice, most homeowners install a granny annexe as a long-term addition to their property.
If a granny annexe exceeds the size limits or does not meet the criteria set out in the Caravan Sites Act, it is generally treated as a permanent building. In these circumstances, the project will usually require full planning permission and must comply with the relevant planning policies and Building Regulations.
Most granny annexes are approved for family use only. If you plan to rent it out, different planning rules apply. We can advise on this during your consultation.
Yes. We offer free, no-obligation site surveys and quotations within a 120-mile radius of our Midlands base, covering Northamptonshire and many surrounding counties.
A well-designed granny annexe can add value and make a property more attractive to buyers looking for flexible or multi-generational living space. However, the effect on property value will depend on factors such as the property, location, annexe specification, planning status and local market.
Our team of down-to-earth experts genuinely care about great garden spaces and excellent customer service. Whether you’re just starting to explore your options or ready to move forward with your project, we’re here to help.
