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Fill out the form and give us brief details.
We will get back to you with an indicative SIPs extension cost, so you know what to expect.
Once you have an idea of the price of a SIPs extension, you can then make an informed decision.

Or call the experts today on 0330 166 0877

Maximise Your Space with SIPs

Traditional cavity wall construction typically uses up to 350mm of wall thickness, which can eat into your usable floor space—especially in smaller extensions. In contrast, SIPs (Structural Insulated Panels) use just 147mm of thickness while still exceeding modern insulation and strength standards.

In a 4m x 5m extension, this difference alone can free up around 2m² of additional internal space—enough for extra storage, a larger dining area, or simply a more open feel. With SIPs, you’re not just building faster and stronger, you’re building smarter.

Space gained with SIPs

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Frequently Asked Questions

Frequently asked questions

What is a SIP panel?
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Structural Insulated Panels (SIPs) are a modern, high-performance construction solution that combine structural strength and thermal efficiency in a single system. They use advanced composite panel technology to deliver superior performance in both residential and light commercial builds.

Each SIP consists of a PUR insulating foam core (Polyurethane) sandwiched between two layers of oriented strand board (OSB). The foam chemically bonds the two layers of OSB to create an extremely strong and thermally efficient system. Produced in a controlled factory environment, the panels can be custom-made to suit almost any design. The result is a lightweight, durable building system that offers excellent energy efficiency, rapid installation, and minimal thermal bridging.

SIPs are engineered, load-bearing, timber-based components suitable for walls and roofs. As they are prefabricated offsite and delivered ready for assembly, they offer significant time and cost advantages. This panelised construction method enables the creation of highly airtight, thermally efficient building envelopes, making SIPs an ideal choice for modern construction projects.

Do I need planning permission to build a garden room?
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Many garden buildings can be installed without planning permission, but it is always a good idea to check with the local planning office before beginning a garden room project.

Customers are welcome to contact us for advice as we have many years of experience in applying for planning permission.
What materials are in a garden room extension kit?
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Our garden room extension kits contain everything the customer needs to construct a garden room, including easy-to-use assembly details.

The main components are the structurally insulated panels or SIPs, that provide the walls and floor of the garden room.

SIPs are made in our own factory and are constructed by sandwiching two structural facing boards together with thermally efficient foam.

The SIPS method of construction gives unrivalled versatility as the panels can be made to measure, providing an ideal solution for the installation of buildings of most sizes. The glazing and door will also be included in the kit when requested.

The kit also includes all the information required for the assembly and installation of the garden room.
How long does it take to build?
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As soon as an order is received, our factory team starts to work on cutting and sizing the SIPs to meet the customer’s requirements.

Once the panels have been cut, including the apertures for windows and doors, the garden room will be fully assembled as part of our quality checking. As the components are disassembled, they are numbered to make it easy to reassemble them on-site.

Delivery of the garden room extension kit usually takes about 10 to 15 days after the order has been received the monies as per your agreed payment terms.
How much does a garden room extension kit cost?
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The final cost of your project will depend on its size and the choice of cladding, roof tiles and glazing.
Once you have decided on the dimensions of your garden room, you can find an indicative cost by using our Quick Quote form.
How strong are SIPs panels?
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Extensions and Garden Rooms created with one of our extension kits will give many years of pleasure and require minimal maintenance as SIP panels do not rot or degrade with time or exposure to the elements.

SIPS panels are up to seven times stronger than timber and can withstand all the wind and weather can throw at them.

Our SIP panels have been subjected to the most rigorous testing and comply with or exceed all British building standards, including British Fire Safety regulations.

We are so confident in the longevity and durability of our SIPS products that our garden room extension kits have a ten year guarantee.
Planning a project?
If you are planning a garden room project and would like to find out more about our extension kits, why not contact our friendly team for more details?
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