If you’re looking for a high-performance external wall insulation solution, Kingspan Kooltherm K5 is a standout choice. Designed specifically for use on masonry walls, K5 offers excellent thermal performance with a lambda value as low as 0.021 W/mK. This means you can achieve low U-values without needing thick insulation layers.
The beauty of K5 lies in its simplicity and efficiency—it’s suitable for both traditional and lightweight polymer-modified render systems and can be fitted externally, making it ideal for retrofit projects. Best of all, it causes minimal disruption, as all work is done from the outside—no need to disturb the interior of the building.
Why Choose Kooltherm K5?
One of the thinnest commonly used insulation boards for external walls, helping meet regulations without bulk.
Especially useful for properties that cannot be insulated internally due to design or occupancy.
A perfect solution for refurbishment or retrofit projects, improving energy ratings with minimal fuss.
Because installation is carried out externally, it does not reduce internal living space, unlike insulated plasterboard.
Offers the added benefit of improving external aesthetics when paired with a render system.
Lightweight and easy to handle, transport, and install.
Part of Kingspan’s premium Kooltherm insulation range, backed by strong technical support.
Available Sizes & Pack Coverage
50mm thick – 1200mm x 600mm boards – approx. 7.2m² per Pack
60mm thick – 1200mm x 600mm boards – approx. 5.76m² per Pack
70mm thick – 1200mm x 600mm boards – approx. 4.32m² per Pack
Frequently Asked Questions
1. Can Kooltherm K5 be installed on existing homes?
Yes, Kooltherm K5 is ideal for retrofit projects. It’s applied to the outside of the building, so there’s no disruption to the interior, making it a convenient choice for occupied homes.
2. Will it affect the appearance of my property?
It can actually enhance the appearance! K5 is typically used with a render system, which can be chosen to match or refresh the look of your home’s exterior. It’s a great way to modernise older buildings.
3. Is Kooltherm K5 difficult to install?
No, it's lightweight and easy to cut and fix. It’s suitable for use by professionals familiar with external wall insulation systems, and Kingspan provides guidance and support for proper installation.
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