Self Contained Garden Annexe Buildings

Growing levels of design sophistication and finish mean that garden annexes are becoming increasingly popular as a way of creating extra living space without the expense of moving or extending your home.

These self-contained garden annexes are often more affectionately referred to as a ‘granny annexe’, created to provide safe and comfortable accommodation of the highest standard, right on your doorstep, yet retaining a great level of independence and autonomy.

Make Room Outside designs and builds garden annexes to match your individual specification and potential use. We focus on creating beautifully crafted, stylish and versatile garden annexes with kitchens or kitchenettes, bathrooms, bedrooms and sitting rooms, where your close relatives can enjoy all the benefits of totally independent living.

It’s the perfect solution for supporting the safety and independence of an elderly or less mobile relative. What’s more, it’s a flexible solution matching other accommodation challenges, such as young people returning from university who aren't yet in a financial position to get on the property ladder.

Is a garden annexe suitable for year-round living?

Absolutely. As with all garden rooms designed and built by Make Room Outside, your annexe will benefit from advanced levels of insulation, guaranteeing warm year-round comfort.

Constructed from approved materials and equipped with capable heating systems, our garden annexes are insulated throughout, including roof, walls and floor, ensuring they remain warm in winter and cool in summer.

These advanced levels of insulation also ensure a peaceful environment, acting as an effective sound barrier, yielding energy savings and ensuring advanced thermal performance.

Planning permission for garden annexe buildings

Planning regulations and building regulations will differ depending on the projected use of the garden annexe. Make Room Outside always recommends seeking advice from your local planning department on planning permission before any work commences on the project.

Where the garden annexe is intended as a permanent and full-time place of residence, planning permission will likely be required. Where it is to be used as occasional overnight accommodation, it may not be required.

The building may fall under the auspices of permitted development, as with many garden rooms, but there are instances where planning permission will be necessary, and this will be dictated by the intended use.

Garden annexes constructed by Make Room Outside are deemed to be permanent and non-transportable buildings and are not governed by the Caravan Act, which was created to provide essential protections and guidelines for both occupiers and local authorities.

If required, our experienced Make Room Outside team can assist with securing the correct planning permission for garden granny annexes, which is a chargeable option subject to a small additional fee.

Top Tips

Research the local council planning permission requirements for building an annexe
Think about the amenities you require, as well as the inherent safety aspects
Don’t forget to consider creating a welcoming outdoor space, too
Choose the best you can afford – remember a garden annexe will add value to your home too

Visit the Make Room Outside Show Village to see the quality and finish of our bespoke garden rooms.

How much does a granny annexe cost?

As a guideline, typical prices for Make Room Outside one bedroom granny annexes start from around £45,000 based on a 6m x 4m footprint (Summer 2025).

Prices will vary depending upon several factors, including:-

Size
Structural materials and plumbing/electrical requirements
Foundation and landscaping requirements
Door and window options and interior finishes
Additional features such as canopy side roof extensions, creating a covered patio area

When considering an investment in a granny annexe, it’s worth remembering the cost of care homes in the UK today. Dependent upon where in the UK you live, annual costs range from £27,000 to £39,000 for residential care, rising to £35,000 to £55,000 when nursing care is required.

Benefits of garden annexes

A professionally designed and built garden annexe or granny annexe provides an extensive range of features and benefits.

Granny annexes provide self-contained accommodation with all the benefits of proximity to supporting family, combining independence and valuable own space with peace of mind for all.
Insulated buildings with heating for year-round independent living space, insulated to offer excellent thermal performance and seasonal comfort.
Granny annexes are ideal for a senior family member or a younger person with a disability, bringing the generations together yet retaining an important level of independence and self-determination.
Exempt from council tax for dependents – granny annexes are exempt from the Council Tax charge when occupied by a dependent relative of the household as their main home, covering those over the age of 65, those with a substantial or permanent disability and those who are severely mentally impaired.
Make Room Outside can design self-contained granny annexes to your individual specification, equipped with everything you need and built to the highest quality standards.
In the future, if no longer required as a granny annexe, the space could be rented out to generate an income or used as additional living space.
Granny annexes will usually add value to a property, providing additional space which can be used in a variety of ways in the future, such as a home office. Typical increases in property values range from 20% to 30%, enhancing the appeal of the property.
In general, properties with an annexe are in high demand and often sell more quickly.

Next steps

If you would like to explore the potential for granny annexe buildings for your home to create additional living space, visit the Make Room Outside show village in Copley, West Yorkshire, or give us a call to chat through your requirements with our friendly and knowledgeable team.