Space 3 S | 6.3m x 3m SIP Garden Room | Fully Installed | Home Office | Gym | Garden Bar | Mainland UK

Fully Installed Space 3 S Garden Room | Home Office | Gym | Garden Bar — Professionally Installed Across Mainland UK

The Space 3 S is our largest single-width garden room — a commanding mono-pitch SIP-panel structure that delivers 18.9m² of genuinely usable, thermally efficient space in a 6.3m x 3.0m footprint. With 97mm polyurethane-core wall and floor panels, a 122mm roof panel, and a wall U-value of just 0.34 W/m²K that exceeds Building Regulations, this is a garden room with the scale and the specification to function as a serious home office, a fully equipped gym, a premium garden bar, or a commercial studio.

At 6.3 metres wide, the Space 3 S has a presence that smaller garden rooms simply cannot match. Full-height glazing runs the length of the front elevation, flooding the interior with natural light and creating a connection to the garden that makes the space feel expansive rather than enclosed. The mono-pitch roofline keeps the profile clean and contemporary — a building that looks like it belongs in an architectural magazine, not a garden centre catalogue.

The price shown includes the full supply and professional installation of your Space 3 S anywhere on Mainland UK, including foundation preparation and installation, EPDM rubber roofing, and windows and doors professionally installed and weather-sealed. There are no hidden costs, no separate groundworks quotes, and no surprises. What you see is what you pay.

Built to Building Regulations — Not Just a Garden Shed

The Space range is engineered to a fundamentally different standard from timber-frame or log cabin garden buildings. The SIP construction delivers airtightness of less than 1 m³/hr/m² at 50 Pascals, Part L compliance, and thermal performance that makes the Space 3 S genuinely comfortable to use year-round without excessive heating costs. This is a building you can work in every day of the year — not just when the weather is kind.

Key Features

• 18.9m² floor area — 6.3m x 3.0m footprint — our largest single-width garden room
• Mono-pitch roof — clean contemporary profile with full-length glazed elevation
• Full-height glazing — floods the interior with natural light across the full 6.3m width
• Corner entry option — flexible positioning to suit your garden
• 97mm SIP wall and floor panels — polyurethane core, prefabricated
• 122mm SIP roof panels — superior thermal performance
• Wall U-value: 0.34 W/m²K — exceeds Building Regulations
• Roof U-value: 0.26 W/m²K — superior thermal performance
• Airtightness: <1 m³/hr/m² at 50 Pascals
• Part L Compliant — UK Building Regulations
• EPDM rubber roof — included as standard. Fully fitted, seamless, and long-lasting. We will never install standard shed felt on any building we are responsible for.
• Foundation preparation and installation — included. No separate groundworks quote.
• Composite DPC strip, ground membrane, and anti-insect and rodent mesh — included as standard — we fit a composite damp-proof strip along the base of the foundation beneath all pressure-treated timber, lay a ground membrane beneath the building, and install anti-insect and rodent mesh as standard on every installation. These measures are not optional extras — they are part of how we build, because we want every building we install to last as long as possible.
• Basic cladding package — included as standard

Product Specifications

What Is Included in the Price?

• Supply and delivery of your Space 3 S
• Foundation preparation and installation — included. Ground screws, concrete slab, or composite pads — assessed and installed as part of the price. No separate groundworks quote.
• Composite DPC strip — included as standard. Fitted beneath all pressure-treated timber at foundation level.
• Ground membrane — included as standard. Laid beneath the building on every installation.
• Anti-insect and rodent mesh — included as standard. Installed on every build — a detail most installers do not include.
• Full structural assembly — prefabricated SIP panels installed to specification
• Windows and doors — professionally installed and weather-sealed
• EPDM rubber roof — included as standard. Fully fitted and seamless.
• Basic cladding package — included as standard
• Site clean-up and handover

Island locations and certain remote areas of Scotland may be subject to additional logistics costs — please contact us prior to ordering.

Optional Upgrades

Personalise your Space 3 S with a range of premium upgrades, available at an additional cost:

• Electrical package (lighting, sockets, consumer unit)
• Bi-fold or sliding door upgrade
• Premium cladding colour and finish upgrades
• Decking installation
• Guttering and drainage
• Internal lining and plastering
• Custom built-in seating
• Bar installation — custom-fitted bar unit

Contact us to discuss your requirements and receive a tailored quote for any upgrades.

Interested? Let’s Talk.

Every project is different. Contact us today and we will get back to you promptly.

Frequently Asked Questions

Do I need planning permission for the Space 3 S?

Quite possibly — at 6.3m x 3.0m and 18.9m², the Space 3 S is a substantial building and planning permission is more likely to be relevant than for smaller models. In many cases it will still fall within Permitted Development rights for residential properties in England and Wales, provided it is used as an ancillary garden building, is sited within the curtilage of a dwelling house, is not forward of the principal elevation, and does not cover more than 50% of the garden area. However, the 6.3m width and 18.9m² footprint mean the 50% coverage rule and boundary setback rules need careful checking. For commercial use, permitted development rules are different. We always recommend confirming with your local planning authority before ordering.

Does the price include everything — foundations, roofing, and cladding?

Yes. Foundation preparation and installation, EPDM rubber roofing, and the basic cladding package are all included. Optional upgrades such as electrical packages, premium cladding, bi-fold doors, and internal lining are available at an additional cost. No hidden costs, no separate groundworks quotes.

What type of foundation does the Space 3 S need?

We assess each site individually and install the most appropriate foundation as part of the price. For most residential gardens, this will be ground screws or a concrete slab given the larger footprint. We will advise you on the best option during the pre-installation survey.

What extra protection do you install at foundation level?

On every installation, we fit a composite damp-proof strip along the base of the foundation beneath all pressure-treated timber. We lay a ground membrane beneath the entire building to manage moisture and suppress weed growth. And we install anti-insect and rodent mesh to prevent ingress beneath the floor — a detail that most garden room installers simply do not include. We do everything we possibly can to make every structure we install last as long as possible.

What is SIP construction and why is it better?

SIP stands for Structural Insulated Panel — a prefabricated building system consisting of a rigid polyurethane foam core bonded between two structural boards. SIP panels deliver exceptional thermal performance, airtightness, and structural rigidity. The Space 3 S achieves a wall U-value of 0.34 W/m²K and airtightness of less than 1 m³/hr/m² at 50 Pascals — performance that exceeds UK Building Regulations and makes the building genuinely comfortable to use year-round.

Can I use the Space 3 S as a year-round home office or gym?

Yes — this is what it is designed for. At 18.9m², there is room for a proper desk setup with a meeting area, or a fully equipped gym with space to move. The SIP construction, Part L compliance, and EPDM roof make it a genuinely four-season building. Please contact us to discuss the electrical package if you would like heating or lighting included as part of the installation.

Can I add electricity, lighting, or a bar?

Yes. Electrical packages, internal lining, custom bar installations, and built-in seating are all available as optional upgrades. Please contact us before placing your order to discuss your requirements and receive a tailored quote.

How long does installation take?

The Space 3 S is typically installed in two to three days, depending on site conditions and foundation type. We will confirm the installation schedule with you in advance.

How long does delivery take after ordering?

Typically 4 to 8 weeks from order confirmation. Please contact us if you have a specific deadline.

Do you install across the whole of the UK?

We install across Mainland UK. Island locations and certain remote areas of Scotland may be subject to additional logistics costs — please contact us before ordering.