Isover Insulation

Cavity Wall insulation is a type of insulation applied within the cavity walls (usually the exterior) of residential and commercial buildings. Many people are familiar with the form of cavity wall insulation that involves blowing small foam pellets into the cavity of existing houses, but modern houses and extensions are instead often built using Cavity Slab insulation batts or boards. Instead of being applied retroactively, this is added during the process of constructing the wall - literally from the ground up. It is designed to “friction fit” between the cavity walls, in between the steel wall ties, and provides effective thermal insulation.

Isover Cavity Wall insulation comes in two varieties - Isover Cavity Wall System 36 and Cavity Wall System 32. The numbers refer to their thermal conductivity value, with the lower number being less conductive a material, and therefore a more effective insulation. It is similar to Knauf Dritherm products and provides largely the same function.

Mineral wool insulation is a type of insulation material made from natural minerals like glass or rock, which are melted down and spun into fibres. These fibres are then compressed into mats, "slabs" or rolls. Mineral wool is known for its excellent thermal insulation properties, as well as its ability to resist fire, moisture, and pests. It is commonly used in residential and commercial buildings to improve energy efficiency by reducing heat transfer through walls, ceilings, and floors. Additionally, mineral wool is favoured for its durability and resistance to mould and mildew, making it a popular choice for both new construction and retrofit projects.

Isover Mineral Wool is rated Euroclass F Reaction to Fire classification, according to BS EN 13501-1. 

Isover are well known for their loft insulation, known as "Spacesaver" insulation roll. It is made from glass mineral wool and is sold in a range of thicknesses from 100mm insulation roll up to 200mm insulation roll. 100mm and 200mm are the most popular sizes. Isover loft insulation is sold in one long roll of insulation, and is perforated in multiple places, so it can be easily split at the correct width to fit your joist spacing. it is then rolled between the joists of your loft "floor" to provide further insulation against cold temperatures.

Isover's Acoustic insulation, known as "partition roll" is a mineral wool insulation roll designed that is most commonly used as internal wall insulation to dampen and reduce the travel of sound between rooms- particularly in bedrooms or hallways and corridors. It can also be used as floor insulation in suspended timber flooring/ceilings when rolled out between joists. It is cut to a 600mm to suit common sizes of stud spacing. They can be used as one 600mm roll or split into 2 x 300mm rolls. The most popular thickness of Isover acoustic roll is 100mm.

At DIY Building Supplies, we've partnered with Saint-Gobain's Isover brand because they're renowned for their pioneering approach to sustainable, high-performance glass mineral wool insulation. Whether you're insulating lofts, cavity walls, or partition spaces, Isover delivers exceptional thermal and acoustic performance that exceeds expectations.

Outstanding Performance Characteristics:

• A1 Euroclass Fire Rating – one of the highest grades available
• Superior thermal conductivity from 0.032 to 0.044 W/mK
• Exceptional acoustic properties for sound reduction
• Non-combustible, water-resistant, and mould-proof

Our Complete Isover Range

Isover Spacesaver – The professional's choice for loft insulation. Pre-perforated at 3 x 386mm and 2 x 580mm for perfect installation between common joist spacing, these rolls make DIY installation remarkably straightforward whilst delivering professional results.

Isover APR 1200 (Acoustic Partition Roll) – Specifically engineered to reduce sound transmission between adjoining spaces whilst providing excellent thermal insulation. Perfect for creating peaceful, comfortable environments in homes and commercial properties.

Isover Cavity Wall Slabs (CWS 32 & CWS 36) – Designed specifically for external cavity walls where condensation build-up is often a concern. These robust slabs provide exceptional thermal performance and long-term durability.

Isover RD Party Wall Rolls – Specifically engineered to diminish flanking transmission through party walls whilst maintaining excellent thermal performance. Essential for apartment complexes and semi-detached properties.

Expert Support That Makes the Difference

What sets DIY Building Supplies apart isn't just our premium Isover range – it's our commitment to your project's success. Our technical team understands the complexities of modern insulation requirements and provides the expert guidance you need to choose the right products for your specific application.

From calculating precise quantities to ensuring Building Regulation compliance, we're here to support every stage of your project. Because at DIY Building Supplies, we don't just supply materials, we deliver solutions.

Ready to start your project? Browse our complete Isover insulation range below, or contact our expert team for personalised recommendations tailored to your specific requirements.