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50mm Kingspan Kooltherm K5 External Wall Board is a premium insulation solution for external walls. With a fibre-free thermoset phenolic core, K5 provides a thermal conductivity of 0.020 W/mK.


Key Features


  • Use in external masonry walls
  • Fibre-free rigid thermoset phenolic core
  • 0.020 W/mK thermal conductivity
  • Easy to handle and install
  • Zero Ozone Depletion Potential (ODP)
  • BBA certified


Technical Specification



Material Type:Phenolic
Pieces Per Pack:10
Sales Unit:Pack
Sales Unit Coverage:7.2m2
Thermal Conductivity:0.02W/mK
Facing:Glass Tissue Based
Application:External Insulation for Masonry Walls



Kingspan Kooltherm K5 External Wall Board is a premium performance insulation solution for installation on external walls. Made up of a fibre-free thermoset phenolic core, this rigid insulation board is suitable for use behind traditional and lightweight polymer modified renders and dry cladding systems. Kooltherm K5 insulation boards have a glass tissue face on either side, and are resistant to the passage of water vapour. 

They are manufactured using a low GWP blowing agent that has zero ODP. With a lambda value of 0.20 W/mK, these 50mm phenolic boards are highly thermally efficient when compared with other insulation boards. Kingspan K5 external wall boards are 1200mm x 600mm in size, making them lightweight and easy to handle and install. They are sold in packs that are wrapped in plastic.

50mm Kingspan Kooltherm K5 external wall board is external insulation for masonry walls. The term masonry wall refers to any wall that is comprised of single units such as stones, rocks, tiles, and blocks that are used in conjunction with mortar to create a solid structure. K5 insulation boards are most efficient when they are installed alongside a range of polymer modified renders within external wall insulation systems.

K5 external insulation is management system certified to ISO 14001: 2015. It is manufactured using a blowing agent that has zero Ozone Depletion Potential and low Global Warming Potential. It has an insulation core of fibre free rigid thermoset phenolic foam, with a compressive strength of 120 kPa at 10% compression.


50mm Kingspan K5 Phenolic Core



Kingspan external wall insulation is comprised of a rigid fibre-free thermoset phenolic core and glass tissue facings on both sides. Kingspan is the only manufacturer in the UK that creates phenolic foam insulation.

The 50mm Kingspan Kooltherm K5 board provides a thermal conductivity of 0.020 W/mK. Thermal conductivity ratings reveal how well an insulation material transmits heat. The lower the number, the better the material will insulate your home. Phenolic insulation has the lowest thermal conductivity rating of all insulation materials.


Kingspan External Wall Insulation Applications


50mm K5 insulation will reduce the amount of heat that you lose through external walls. Homeowners lose over a third of the heat in their homes through the walls. We recommend external wall insulation from Kingspan for both new build and refurbishment projects. Kingspan has decades of experience creating high-performance insulation materials that will improve the thermal envelope of your domestic or commercial space.


Kooltherm K5 Insulation Thicknesses


You can purchase external wall insulation from Kingspan in 50mm, 60mm, and 70mm thicknesses. Our range of thicknesses makes it easy for insulation installers to find the perfect fit. You can get the same great thermal protection from Kingspan K5 boards as you can with other boards whilst still meeting your project requirements. Our selection of thicknesses is also ideal for people who want to replace a board in their existing build-up without starting from scratch.

50mm Kingspan Kooltherm K5 External Wall Insulation Board 1200mm x 600mm

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