Kingspan Greenguard GG300R XPS Insulation Board

Kingspan GreenGuard GG300R is a robust extruded polystyrene (XPS) insulation board specifically engineered for applications where high strength and moisture resistance are essential. With a thermal conductivity of 0.033 W/mK, this rigid insulation board delivers dependable thermal performance across a wide range of specialist projects. Its exceptional compressive strength makes it particularly suited for high-load environments like inverted flat roofs, basements, car park decks, cold storage floors, and heavy-duty industrial settings. Ideal for building insulation applications, this product helps create an efficient thermal envelope. It also works seamlessly with insulation systems. Whether you're working on a commercial project or an intensive residential build, GG300R can withstand pressure from both vehicles and equipment.

Moisture Resistance and Long-Term Performance

Thanks to its minimal water absorption and resistance to ground moisture, Kingspan GreenGuard GG300R maintains its thermal integrity in damp and below-ground conditions. It’s also designed to handle freeze-thaw cycles without degradation, making it an excellent choice for external insulation beneath waterproofing membranes or green roof systems. The board is easy to install, lightweight yet strong, and compatible with most common building materials and finishes.

Available Sizes

Kingspan GG300R comes in multiple thickness options to suit your specification needs: 30mm (1250mm x 600mm) – covers 10.5m² per Pack 40mm (1250mm x 600mm) – covers 7.5m² per Pack 50mm (1250mm x 600mm) – covers 6m² per Pack 60mm (1250mm x 600mm) – covers 5.25m² per Pack 80mm (1250mm x 600mm) – covers 3.75m² per Pack 100mm (1250mm x 600mm) – covers 3m² per Pack 120mm (1250mm x 600mm) – covers 2.25m² per Pack 150mm (1250mm x 600mm) – covers 1.5m² per Pack

Key Features

Rigid XPS insulation for high-load bearing applications Thermal conductivity of 0.033 W/mK Withstands vehicle and heavy equipment loads Excellent resistance to moisture and ground penetration Freeze-thaw resistant for long-term durability Compatible with green and inverted roof systems

Frequently Asked Questions

1. Can Kingspan GG300R be used below ground?

Yes, it is ideal for below-ground applications like **basement walls and floors** due to its moisture resistance and compressive strength.

2. Is this insulation suitable for car parks or industrial floors?

Absolutely. GG300R is designed to handle **heavy-duty loads**, making it perfect for areas that experience frequent vehicle traffic or industrial use.

3. Does this insulation absorb water over time?

No, GG300R is designed with **very low water absorption** and maintains performance even in wet or humid conditions, including freeze-thaw environments.

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At JJ Building Materials, we're committed to supplying quality building products at competitive prices, backed by the service and expertise you'd expect from an established independent merchant. Whether you're a trade professional managing large-scale projects or a homeowner taking on a DIY renovation, we're here to help you find the right products for the job.

As part of the JJ Roofing Supplies Group, we build on decades of experience supplying construction materials across the UK. We've expanded beyond roofing to offer a growing range of building materials, including timber, insulation, landscaping products, plumbing supplies, flooring, doors, bricks, fencing, garden buildings and much more – all available to order online with nationwide delivery.

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Every order is personally reviewed by our experienced team to ensure everything is correct before dispatch. We offer delivery from as little as the next working day on selected products, so please refer to the dark blue Estimated Delivery box above for the expected delivery timeframe for this item.

We work with trusted manufacturers and specialist delivery partners to ensure your order arrives safely and on time. You'll receive tracking details once your order has been dispatched, and if we need to confirm any delivery details, one of our team will contact you directly to keep everything running smoothly.

Roof Tiles & Fittings:

We recommend ordering an additional 10% of roof tiles to allow for any breakages that may occur during delivery or handling. Roof tiles are naturally fragile, and having a few extra on site helps prevent delays and ensures your roofing project can be completed without interruption.

Multiple Products from the Same Supplier

If you're ordering multiple products from the same supplier, your order will be dispatched together once all items are ready. This means the longest lead time will apply.

If you need part of your order sooner, please call us on 01202 113233. We can arrange a split delivery, although an additional shipping charge will apply.