Kingspan TW50 Thermwall Partial Fill Cavity Insulation Board

Kingspan Thermawall TW50 is a high-performance insulation board designed specifically for use in partial fill cavity wall applications. With a thermal conductivity of just 0.022 W/mK, this PIR (polyisocyanurate) board helps achieve impressive thermal efficiency with less thickness—ideal when space and performance are both priorities. TW50 insulation boards are lightweight and easy to handle, making them a popular choice for both new build and retrofit projects. Whether you're a professional contractor or a confident DIYer, these boards are easy to cut to size, position, and install, helping save time on site.

Performance-Driven Design

These boards come with low emissivity foil facings that significantly enhance the thermal resistance of the air cavity, boosting energy efficiency. TW50 also helps maintain a clear cavity, which is vital for moisture resistance, keeping your internal structure protected from the elements over the long term. If you're looking for an insulation solution that balances performance, practicality, and ease of installation, Thermawall TW50 is a dependable choice.

Available Sizes

Kingspan TW50 boards are available in a range of thicknesses to suit your build needs: 40mm (1200mm x 450mm) – covers 6.48m² per Pack 50mm (1200mm x 450mm) – covers 5.4m² per Pack 60mm (1200mm x 450mm) – covers 4.32m² per Pack 70mm (1200mm x 450mm) – covers 3.24m² per Pack 75mm (1200mm x 450mm) – covers 3.24m² per Pack 100mm (1200mm x 450mm) – covers 2.7m² per Pack

Key Features

High-performance PIR insulation with thermal conductivity of 0.022 W/mK Maintains a clear cavity, reducing the risk of moisture bridging Low emissivity foil enhances thermal resistance of cavity Lightweight and easy to cut and install

Frequently Asked Questions

1. Can Thermawall TW50 be used in all types of cavity walls?

Yes, it's designed for use in **partial fill masonry cavity walls** and is suitable for both domestic and commercial buildings.

2. How does TW50 help with moisture control?

Its design ensures a **clear air cavity is maintained**, helping prevent moisture transfer and protecting internal walls from damp.

3. Is additional insulation needed with TW50?

That depends on your target **U-values** and local building regulations. In many cases, TW50 can meet requirements on its own, but it's best to check with your architect or energy assessor.

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