Kingspan KoolTherm K118 Insulated Plasterboard x 1200mm x 2400mm

Kingspan KoolTherm K118 Insulated Plasterboard 1200mm x 2400mm

Kingspan KoolTherm K118 is a premium insulated plasterboard designed for high-performance drylining applications. Whether you’re upgrading the thermal efficiency of solid walls or working on a refurbishment project where space is limited, this innovative board offers outstanding insulation in a slim profile. Combining insulation, drylining and vapour control in one product, KoolTherm K118 helps create warmer, more energy-efficient interiors with less material and installation time. It’s suitable for both mechanical fixing and adhesive bonding, working seamlessly on solid brick or stone walls — even those with existing linings.

Why Choose Kingspan KoolTherm K118?

KoolTherm K118 is one of the thinnest internal wall insulation (IWI) solutions on the market, making it perfect for projects where every millimetre counts. Its exceptional thermal conductivity of just **0.019 W/mK** ensures maximum performance in minimal space. Lightweight yet durable, the boards are easy to handle, transport, and fit — helping you achieve quick, clean installations and faster heating response times. With integrated vapour control and drylining layers, this system simplifies wall upgrades, improving comfort and energy efficiency while reducing condensation risks. It’s especially ideal for buildings that can’t be insulated externally due to design, planning or heritage restrictions.

Pack Sizes

Insulation Thickness	Overall Thickness	Boards Per Pack	Pack Coverage
25 mm	37.5 mm	21	60.48 m²
30 mm	42.5 mm	18	51.84 m²
40 mm	52.5 mm	15	43.20 m²
45 mm	57.5 mm	14	40.32 m²
50 mm	62.5 mm	12	34.56 m²
60 mm	72.5 mm	11	31.68 m²

FAQs

Can Kingspan KoolTherm K118 be used on existing plastered walls?

Yes — KoolTherm K118 can be bonded directly to existing plaster or masonry surfaces using mechanical fixings or adhesive, making it ideal for refurbishment projects.

Is a separate vapour control layer required?

No — the board includes an integrated vapour control layer, so there’s no need for an additional membrane in most applications.

What makes KoolTherm K118 different from standard insulated plasterboards?

KoolTherm K118 uses advanced phenolic insulation with an ultra-low thermal conductivity of **0.019 W/mK**, making it one of the thinnest and most efficient drylining solutions available.

Check out our full range of insulation.

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