Kooltherm Cavity Closer


Premium performance insulated cavity closer

Kingspan Kooltherm Cavity Closer is a uPVC extrusion with a premium performance fibre-free rigid thermoset phenolic core, for use in England and Wales only.

It provides a simple and efficient method of closing cavities around openings in masonry cavity walls, and has a thermal conductivity of 0.022 W/mK.


Our product brochures include construction details, handling advice and installation guidance.

Kooltherm Cavity Closer

Technical & downloads

Thermal conductivity  0.022 W/mK
Sheathing uPVC extrusion
Core Premium performance rigid thermoset phenolic insulant manufactured with a blowing agent that has zero Ozone Depletion Potential (ODP) and a low Global Warming Potential (GWP)
Length 2.4m
Available widths 50, 75, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145 and 150 mm
Note that sections can be joined together to suit cavity widths up to 300 mm
There are potential restrictions placed upon this product which vary dependant on building type, height, construction and location. For guidance regarding the routes to compliance for meeting the fire safety requirements of the Building Regulations / Standards, refer to the relevant links to Government websites here.

Learn more


Net Zero Energy / Renewable Energy Kingspan Kooltherm Cavity Closer is manufactured in our Selby, North Yorkshire facility. By the end of 2020, 100% of the non-renewable operational energy used in manufacturing processes in this site will be matched through the use of renewable energy and the purchase of renewable energy certificates (to offset any remaining non-renewable energy use). Visit our Net Zero Energy area to learn more.
Net Zero Carbon manufacturing Our groupwide aim is to achieve net zero carbon (CO2e) emissions (scope 1 & 2) from our manufacturing activities by the end of 2030. For more info, visit Planet Passionate.
Waste to Landfill At Selby, we currently send 0% of our manufacturing waste to landfill.
Our Planet Passionate goal is to send zero waste to landfill by 2030.
Responsible sourcing This product is certified 'Excellent' to BES 6001 (Framework Standard for the Responsible Sourcing of Construction Products) for our Pembridge manufacturing site. 
Kingspan Kooltherm Cavity Closer is manufactured at one site and offers the following sustainability performance.

Responsible sourcing

Kingspan Kooltherm Cavity Closer produced at Kingspan Insulation’s Selby, North Yorkshire manufacturing facility is certified to BES 6001 (Framework Standard for the Responsible Sourcing of Construction Products) ‘Excellent’.
Planet Passionate
Through our new Planet Passionate 10-year groupwide sustainability programme, we aim to make significant advances in the sustainability of our business and of our products.

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