Kingspan Kooltherm K108 Partial Fill Cavity Board Insulation

When you're aiming for top thermal performance without compromising space, Kingspan Kooltherm K108 is a smart insulation choice. Designed for use in partial fill cavity wall constructions, K108 offers an impressively low thermal conductivity of 0.019 W/mK—one of the best in its class. This allows you to meet U-value targets with a slimmer insulation board compared to standard alternatives, giving you more flexibility in your wall design. Whether you’re building new or upgrading existing structures, K108 is a practical option. Its slim profile not only helps reduce the thickness of external walls but can also boost natural daylight in internal spaces by allowing larger window openings. It’s ideal for energy-conscious projects where every bit of space and performance matters.

Benefits of Kingspan K108

Exceptionally thin insulation with excellent thermal performance, perfect for achieving compliance without bulky build-ups. Slimmer walls make room for larger window areas, which can increase natural light inside the building. Designed to maintain a clear cavity, ensuring resistance to moisture penetration and long-term reliability. The low emissivity foil facing adds extra thermal resistance to the cavity, improving overall wall performance. Lightweight and easy to handle, K108 makes installation straightforward and efficient. Compatible with BIM systems to aid digital project planning.

Available Board Sizes & Coverage

50mm thick – 1200mm x 450mm – approx. 5.4m² per Pack 60mm thick – 1200mm x 450mm – approx. 4.32m² per Pack 75mm thick – 1200mm x 450mm – approx. 3.24m² per Pack 100mm thick – 1200mm x 450mm – approx. 2.7m² per Pack

Frequently Asked Questions

1. Can Kingspan K108 be used in all types of cavity wall construction?

K108 is specifically designed for **partial fill masonry cavity walls**. It provides excellent thermal performance while maintaining a clear air cavity, which is crucial for moisture resistance.

2. Does it require any special tools or fixings for installation?

No specialist tools are needed. The boards are **lightweight and easy to cut**, and they fit between standard wall ties. Just make sure the cavity is clean and the boards are installed snugly for best performance.

3. How does K108 compare to full-fill insulation?

While full-fill options may offer slightly higher thermal mass, **K108 excels in moisture resistance and design flexibility**. It’s a great option when you want high performance without filling the entire cavity, especially in wetter climates.

Check out our full range of insulation.

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