42.5mm Kingspan Kooltherm K118 Insulated Plasterboard

42.5mm K118 from Kingspan Kooltherm is a high-performance insulated plasterboard engineered for mechanically fixed and adhesively bonded insulated drylining systems. This product delivers exceptional thermal performance with a thermal conductivity of 0.019 W/mK, enabling slim wall constructions without compromising on insulation quality. Combining insulation, drylining, and vapour control in a single board, it works effectively on solid stonework and brickwork, whether pre-lined or not.

The 42.5mm Kooltherm Kingspan offers significant advantages for internal wall projects. As one of the thinnest Internal Wall Insulation (IWI) solutions available, it maximises usable floor space in buildings where external insulation is not feasible. The integrated drylining and vapour control layer simplifies installation, whilst its lightweight nature ensures straightforward handling and fixing.

Properties

Model: 42.5mm K118

Thickness: 42.5mm

Pack Quantity: 18 sheets

Pack Weight: 486.26kg

Dimensions: 2,400mm x 1,200mm x 42.50mm (30mm Phenolic PIR bonded to 12.5mm Plasterboard)

Length: 2400mm

Width: 1200mm

Compressive Strength: >100 (kPa)

Material: Phenolic core ǀ Gypsum plasterboard

R-Value: 1.55m2K/W

Thermal Conductivity: 0.019 W/mK across all thicknesses.

Fire Classification: Euroclass C-s1, d0

Coverage: 51.84m2

Insulation Material: 42.5mm Kooltherm K118 is a premium-grade, low-lambda rigid thermoset phenolic pir insulation.

Finish: Kraft facing ǀ Composite foil

Front Facing: The front surface comprises tapered-edge gypsum-based plasterboard, compatible with dryjointing compounds and plaster skimming.

Reverse Facing: The reverse side of Kingspan K118 features a low-emissivity composite foil layer, factory-bonded to the insulation core.

Applications: Internal Walls ǀ Roofs ǀ Ceilings

BBA Certified: Yes (no. 16/5299)

Vapour Control Layer: Yes, built in

Fixing method: Dot and Dab ǀ Mechanically Fixed

Decoration: Skim plaster

Features: Premium-performance insulated plasterboard

About

This premium rigid thermoset phenolic insulation board delivers outstanding thermal performance at 0.019 W/mK whilst serving triple duty as insulation, drylining, and vapour barrier. The product resists air leakage and moisture transmission, making it ideal for new builds, retrofits, and refurbishment work. Installation is straightforward, and the board is manufactured using a zero-ODP, low-GWP blowing agent, supporting environmentally responsible construction practices.

Applications

The 42.5mm Kingspan board suits diverse construction scenarios, including cavity masonry wall systems, solid wall construction, timber frame assemblies, ceiling installations, metal furring applications, direct mechanical fixing to masonry, and both horizontal and sloped ceiling linings. It performs equally well in Masonry Wall constructions and timber-framed structures.

Benefits of Kooltherm

Deploying the slim-profile Kingspan k118 insulated plasterboard preserves valuable internal floor area, boosting lettable space and enhancing property value for buyers and tenants alike.

Sustainability

Kingspan has integrated Kooltherm into its Planet Passionate sustainability commitment.

The core

The 42.5mm K118 insulated plasterboard features a high-performance, rigid, thermoset, fibre-free phenolic core manufactured with a zero-ODP, low-GWP blowing agent.

About Kingspan Insulation

Kingspan Insulation Ltd is part of Kingspan Group plc, a leading European construction products manufacturer. The Kingspan insulation Group, established in the late 1960s and publicly listed, operates from headquarters in Kingscourt, County Cavan, Ireland.

Info

Browse our full Kingspan range and filter by thickness or coverage using the left-hand menu. For project-specific advice or bulk quotations, contact our team by phone on +4402038839057, email sales@insulationbee, or use Live Chat for the best UK Insulation prices.