Kingspan Kooltherm New Lower Lambda Products - Frequently Asked Questions


Kingspan Insulation has launched a new ultra-low lambda cavity board which offers a thermal conductivity of just 0.018 W/m.K.

The BBA-certified Kingspan Kooltherm K106 and K108 cavity boards feature Kingspan’s fibre-free thermoset phenolic insulation core. This allows for a U-value of just 0.17 W/m2.K to be achieved, with an overall cavity of just 100mm in a standard masonry construction.

The K106 cavity board can installed with a mere 10mm air gap instead of the standard 50mm that is required in a standard partial fill cavity wall construction. It also features a water-tight and vapour-open polypropylene fleece outer facing which protects against moisture penetration.

All of this means that building envelope requirements can be met or exceeded without sacrificing space or moving away from preferred cavity sizes.

Manufactured with a blowing agent that has no Ozone Depletion Potential (ODP) and very low Global Warming Potential (GWP), the cavity boards are non-deleterious, easy to install and are unaffected by air infiltration.

Kingspan Kooltherm K106 and K108 are certified to BES 6001 (Framework Standard for the Responsible Sourcing of Construction Products) ‘Excellent’.

What is a 'lambda' Value?

The lambda of a product is its thermal performance. The lower the lambda value, the more difficult it is for heat to pass through. Therefore thermal performance is improved and a reduced thickness of insulation is needed to achieve the desired U-value.

What is the lambda value of the new Kingspan Kooltherm products?

The new products have a lambda value of just 0.018 W/m.K across all thicknesses.

Here are the thicknesses required for commonly used insulation materials to achieve the same level of thermal perfomance:

Lambda W/m.K Type of Insulation Thickness

0.018