75mm Kooltherm K103 is a high-performance floor insulation board engineered for use beneath solid concrete or suspended timber floors. Delivering thermal conductivity of 0.019 W/mK, this board achieves outstanding thermal performance in minimal thickness. Suitable for both new construction and renovation work, it represents a premium choice for floor insulation applications.
Brand: Kingspan
Thickness: 75mm
Length: 2400mm
Width: 1200mm
Dimensions: 2,400mm x 1,200mm x 75mm
Coverage: 11.52m2
Density: 40kg/m3
Compressive Strength: >120 (kPa)
Material: Premium performance lower-lambda rigid thermoset phenolic insulation core.
Profile: Square Edge
R-Value: 3.90m2K/W
Thermal Conductivity: Kingspan K103 maintains thermal conductivity of 0.019 W/mK across all thicknesses.
Weight: 2.67 kg (Approximate density of 3.70 kg/m2 at 100mm thickness)
Fire Classification: Achieves Euroclass C-s2,d0 to EN 13501-1: 2018.
Vapour Resistivity: 370MNs/gm
Facings: Glass tissue based facing, autohesively bonded to both sides during manufacture.
Finish: Glass tissue facings
Pack Quantity: 5
Applications: Floor insulation ǀ Underfloor Heating Insulation
BBA Certified: Yes (no. 16/5299)
Vapour Control Layer: Yes
Features: Premium ǀ Non-deleterious
75mm Kooltherm floor insulation boards feature lightweight construction, enabling straightforward transportation, handling, and installation on site.
Manufactured at Kingspan Insulation in Pembridge, Herefordshire, the 75mm Kooltherm K103 incorporates glass tissue facing bonded to the insulation core during production. Both sides of the board feature this facing, providing robust and long-lasting protection.
The 75mm K103 Phenolic insulation core comprises premium performance rigid thermoset phenolic material. This fibre-free formulation uses a blowing agent with zero Ozone Depletion Potential (ODP) and minimal Global Warming Potential (GWP), delivering an environmentally responsible insulation product with exceptional thermal properties.
Browse our full Kingspan range and refine by thickness or coverage using the left-hand filters. For product suitability advice or bulk quotations, contact us on +4402038839057, email sales@insulationbee, or use Live Chat for the best UK Insulation prices.








