LUNA 5M x 4M Garden Room

Spacious Garden Room for Modern Living

LUNA 5M x 4M

£22,950 + VAT

The LUNA 5m x 4m is our largest pre-designed garden room, offering generous internal space for those looking to create a statement outdoor room for both everyday use and entertaining.

Like all Backyard Cabins, LUNA is built with quality, comfort, and long-term performance in mind. Its spacious layout makes it ideal for hosting, working, relaxing, or combining multiple uses within one refined, well-proportioned garden room.

An extended front decking area can be added to enhance the connection between indoor and outdoor living, creating a natural space for seating, entertaining, or simply enjoying the garden.

Angled exterior view of the LUNA 5m x 4m garden room with decking, shown at dusk within a landscaped garden
Front view of the LUNA 5m x 4m garden room with large double-glazed doors open, revealing a styled interior used as a combined living and workspace

Design That Makes the Difference

The LUNA 5m x 4m garden room has been carefully designed to maximise space, comfort, and usability, creating a well-balanced layout that works beautifully for a wide range of uses.

With 18 square metres of internal floor space, LUNA offers generous room for working, entertaining, relaxing, or combining multiple functions within one versatile garden room.

Fully insulated throughout the walls, floor, and roof, LUNA is designed for comfortable, year-round use.

A horizontal window is included as standard to bring in natural light, with the option to add a floor-to-ceiling vertical side window if you’d like to further tailor the layout or increase light and outlook.

Interior view of the LUNA 5m x 4m garden room showing a styled, flexible space used for both work and relaxation

The Finer Details

Every element of the LUNA garden room is carefully considered to balance light, comfort, and long-term performance.

Large double-glazed openings at the front of the cabin create a bright, welcoming interior and a strong connection to the outdoors, while a fixed double-glazed window helps distribute natural light throughout the space.

Inside, matte black spotlights are fitted as standard, providing practical, well-placed illumination with a clean, contemporary finish suitable for both work and relaxation.

Externally, LUNA is finished in Thermowood cladding, chosen for its durability, stability, and natural appearance. Over time, the timber weathers gracefully, allowing the cabin to sit comfortably within its garden setting.

The result is a spacious garden room where design, materials, and usability work seamlessly together.

Illustration showing an example layout of the LUNA 5m x 4m garden room used as a wellness and relaxation space, including yoga and seating areas

Multiple Uses

The LUNA 5m x 4m garden room is designed as a flexible, multi-purpose space that can adapt to a wide range of uses over time.

It works equally well as a garden office, studio, summerhouse, treatment room, workshop, or creative space, but the layout is intentionally open — allowing you to shape the room around how you want to use it, rather than limiting it to a single function.

The illustrated layout shown demonstrates one possible configuration, combining a calm wellness or yoga area with a relaxed seating space. This is provided as inspiration only, helping to visualise how LUNA can comfortably support multiple uses within one generous, well-proportioned garden room.

What’s Included

The base price includes a complete, fully installed garden room designed for year-round use, offering generous internal space suited to shared use, multi-functional layouts, and more open, comfortable environments.

Premium Exterior

High-quality Thermowood or carefully selected, durable softwood cladding, chosen for its stability, longevity, and natural ageing over time.

Weatherproof Roofing

Firestone EPDM rubber membrane with a 20+ year life expectancy, providing long-term protection against the elements.

High-Quality Glazing

Aluminium or uPVC double-glazed doors and windows, designed to maximise natural light while maintaining thermal efficiency.

Fully Insulated Structure

SIPs panel construction (walls, floor, and roof) delivers excellent thermal performance and year-round usability.

Interior Finish

Internal walls and ceiling are plastered and painted in matte white as standard, creating a clean, bright, ready-to-use space.

Electrical Package

Internal LED downlights, matte black external porch spotlights, 4x double plug sockets (white as standard), and a dedicated consumer unit are all fully installed within the cabin, with all internal electrics completed and ready for connection. A qualified electrician will simply need to run a supply from your main property to the cabin.

Professional Installation

Your cabin is built on-site by our experienced team, ensuring a precise, high-quality finish.

Waste Removal

All waste generated during installation is removed and responsibly disposed of by our team, leaving your garden clean, tidy, and exactly as we found it.

Planning-Friendly Design

Designed under 2.5m in height to fall within most permitted development guidelines.

Warranty

10-year structural warranty for long-term peace of mind.

For full details on materials, construction methods, and performance, visit our Garden Room Design & Build Information page.

What’s Not Included

To allow flexibility depending on your garden and requirements, the following are not included in the base price:

  • VAT

  • Groundworks (e.g. ground screws or concrete base)

  • Electrical connection from the main house

  • Heating or air conditioning systems

  • Optional upgrades and bespoke features

Optional Extras

+ £2100: Ground screws supply and install.

+ £1650: Karndean LVT flooring.

+ £700: Opening double-glazed window.

+ £700: Integral blinds on bi-fold doors.

+ £150: Custom coloured bi-fold door.

+ £1800: Air conditioning unit. Hot and cold.

+ £550: WI-FI controlled Radiator.

+ £800: Matte black cladding.

+ £2250: Ply Lined interior finish.

+ £3500: Soundproofing.

• Additional window: Price on request

• Buster and Punch lighting and electrical details: Price on request.

• Extended, raised decking area: Price on request.

• Full electrical installation: Price on request.

- £3000: Raw internal finish.

Optional Buster + Punch light fittings shown as a premium lighting upgrade for our garden rooms
Side view of the LUNA 5m x 4m garden room showing external cladding, planting, and reflections in the window glass

Exploring Cabin Characteristics

For full details on how our cabins are designed and built, visit our Information page.

There, we take a closer look at the core elements that define every Backyard Cabin. This includes how our cabins are constructed, why specific materials are chosen, how insulation and structure work together for year-round comfort, and the design decisions that influence durability, performance, and appearance.

The Information page is designed to give you a clear understanding of what goes into our garden rooms, helping you make an informed decision and see how our approach differs from more generic off-the-shelf garden buildings.

LUNA 5m x 4m - Request Your Personalised Quote

  • A tailored price breakdown

  • installation timeline

  • Site suitability advice

No pressure. Just clear information to help you decide.

FAQs

Do I need planning permission for the LUNA garden room?

1

In most cases, no. The LUNA is designed under 2.5m in height to fall within permitted development guidelines, meaning planning permission is typically not required.


How long does it take to install a 5m x 4m garden room?

2

Installation is typically completed within around three weeks once the base is prepared, depending on site access and conditions.


Is the LUNA garden room suitable for year-round use?

3

Yes. The LUNA is built using fully insulated SIPs construction, ensuring it remains warm in winter and comfortable throughout the year.


What is the LUNA garden room best suited for?

4

The LUNA offers a generous internal footprint, making it ideal for shared workspaces, family use, larger studios, or multi-purpose garden rooms that require more space and flexibility.

Schedule your free consultation today.