Quick Summary
A garden room is a cost-effective and flexible way to add usable space to your home. Perfect for a home office, gym, yoga studio, study space, or hobby room, garden rooms can be customised to suit your lifestyle. Costs, planning permission, and construction timelines depend on size, design, and materials, but with the right guidance, your project can be smooth and stress-free.
What Is a Garden Room?
A garden room is a freestanding structure in your garden that provides extra living or working space without altering the main house. They are quick to install, highly versatile, and suitable for a range of uses – from personal gyms and office spaces to creative studios and leisure areas.
Do You Need Planning Permission?
Most garden rooms fall under permitted development rights, meaning planning permission is usually not required. A garden room will typically qualify if it:
- Is single-storey with a maximum eaves height of 2.5m and overall height of 4m (dual-pitched roof) or 3m (other roofs)
- Is not built in front of the principal elevation
- Is no closer than 2m to a boundary if taller than 2.5m
- Has no verandas, balconies, or raised platforms exceeding 0.3m
- Covers no more than half the land area around the original house
Original house refers to the property as it was first built or as it stood on 1 July 1948 if older.
When Planning Permission Is Required
Some homes require full planning permission:
- Flats and maisonettes
- Converted houses
- Certain new builds
- Listed buildings
- Properties in conservation areas, national parks, Areas of Outstanding Natural Beauty, or World Heritage Sites
In protected areas, garden room size allowances may be reduced.
Uses for Your Garden Room
Garden rooms are easier to install when used as offices, gyms, yoga studios, workshops, or hobby spaces. Occasional sleeping, e.g., with a sofa bed, is usually fine, but regular overnight use or self-contained accommodation requires planning permission and building regulations compliance.
Lawful Development Certificates
If you want peace of mind, apply for a Lawful Development Certificate from your local authority. This certifies that your garden room complies with planning regulations and can help avoid future disputes or issues when selling your home.
Do You Need an Architect?
While some garden rooms are modular and ready to install, more complex or bespoke designs benefit from an architect. They can:
- Deliver a custom design tailored to your needs
- Handle planning permission or lawful development certificate applications
- Advise on building regulations and compliance
Building Regulations for Garden Rooms
Compliance depends on size, placement, and intended use:
- Not required for single-storey garden rooms under 15m² with no sleeping accommodation
- Required for rooms over 15m² near boundaries or containing sleeping spaces
- Electrical installations require a compliance certificate from a registered electrician
Even if exempt, consulting an architect ensures safety, longevity, and legal compliance.
Construction Timeline
Construction time varies by design:
- Modular garden rooms: pre-built off-site, installed in a few days
- Bespoke garden rooms: custom-built, 4–6 weeks depending on scale
- Small shed-like rooms: 1–2 weeks
Cost of a Garden Room
Costs depend on design, materials, and purpose:
- Modular garden rooms: £2,000–£30,000
- Bespoke garden rooms: £800–£1,600 per m²
Factors affecting price include insulation, heating, glazing, flooring, and year-round usability.
Garden Room Design Ideas
Garden rooms are highly versatile, perfect for:
- Home office or study
- Yoga or fitness studio
- Home gym or spa
- Bar or games room
- Music or cinema room
- Hobby space or workshop
- Personal library
How NABC Can Help You Find Accredited Builders
For a smooth, professional project, hire NABC-accredited builders. Every builder in our network is fully vetted for quality, reliability, and compliance with building regulations, giving you peace of mind.
NABC can help you:
- Find local accredited builders with proven experience in garden rooms
- Compare quotes from vetted professionals
- Ensure your project is completed safely, on time, and to a high standard
Using an NABC-approved builder reduces risk, improves efficiency, and guarantees quality. Start your garden room project with trusted experts through www.nabc.org.uk.
Transform your garden into a stylish, functional space with a bespoke or modular garden room – designed to your needs and built by trusted, accredited professionals.