Help to reduce heat loss through external walls with cavity insulation

Cavity wall insulation either fills or partially fills the gap between the layers of an external wall, and can contribute to the thermal performance of a building. Without it, the building can be thermally inefficient, leading to increased energy consumption.

Take a closer look at the benefits of cavity wall insulation

There are lots of benefits to using mineral wool cavity wall insulation, from improving energy efficiency to fire performance. Let’s look at the core elements.

Thermal insulation

The small pockets within the mineral wool structure trap air, which is a poor conductor of heat, and significantly reduces heat transfer, making mineral wool an effective thermal insulator. Used as part a system to provide thermal insulation, mineral wool can help to improve thermal efficiency and reduce overall energy costs.

Sustainability 

Our Isover glass wool products manufactured in the UK contain 82% recycled glass. This is a combination of 52% externally sourced recycled glass and 30% internally sourced glass cullet. They’re produced in plant where all electric equipment is powered by 100% renewable electricity.

Reaction to fire 

A significant number of our Isover glass mineral wool products achieve Class A1 reaction to fire to BS EN 13501-1, this is the highest level of performance. Please check Declaration of Performance for individual product’s reaction to fire classification.

Ease of install

Mineral wool cavity wall insulation comes in slabs, making installation easier as the slabs maintain their shape without slumping. They are designed to fit the recommended cavity width and are secured using standard wall ties with retaining clips—no separate mechanical fixings required.

Flexible specifications

Isover cavity wall insulation slabs are available in a range of thicknesses, giving you flexibility to meet different cavity sizes and thermal requirements.

Mineral wool cavity wall insulation can be beneficial for thermal insulation and energy efficiency. Certified by the British Board of Agrément (BBA Certificate No. 18/5560), Isover Cavity Wall Slab (CWS) 32 is fit for use in defined full fill and partial fill masonry cavity wall applications if installed, used and maintained as set out in the certificate. Please read the certification available to download here for full details and restrictions.

Get to know mineral wool insulation for cavity walls with these articles written by our development teams and insulation specialists.