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Insulation for Internal Solid Walls

High performance PIR insulation boards for internal solid walls suitable for both direct bonding (‘dot and dab’) and mechanical fixing installation.

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It’s an oft-quoted statistic that in 2050 we’ll still be using 80% of the buildings we use today. Meeting the country’s targets for reducing carbon emissions is therefore heavily dependent on finding a way to successfully retrofit existing building stock to bring it up to a standard that reduces energy demand and provides occupants with healthy, comfortable places to live and work.

Traditional solid walled properties have no cavities to be filled with insulation, and many cannot have insulation installed to the outside of the wall - whether for practical or aesthetic reasons. Insulating internally is therefore the only option, and one that must be done sensitively.

Buildings that have stood for decades, especially in locations exposed to the elements, were not designed with modern building materials in mind. Rushing to apply insulation materials like high performance insulation boards to the inside of the walls might solve one or two problems, such as excessive heat loss, but can cause new problems by upsetting the moisture balance of the building fabric.

Upgrading the building fabric will typically require a holistic approach, especially because room sizes and space constraints have to be taken into account when designing the most appropriate solution. Balancing insulation thicknesses against available space to avoid potential knock-on effects later, and addressing thermal bridging, is an important part of the design process.

Airtightness and controlled ventilation may need to be considered along with improvements in thermal performance. Celotex PL4000 can be mechanically fixed or adhered to masonry walls using ‘dot and dab’ plaster. With an insulation thickness as low as 15mm, it can also be used to line door and window reveals and help maintain continuity of the building’s thermal envelope.

The composite facing to which the plasterboard is bonded features an aluminium layer sufficient to act as an air and vapour control layer - including the internal upgrade of existing solid walls, subject to appropriate moisture assessment in accordance with regulatory standards, such as BS 5250 (control of condensation in buildings).

* PL4000 only applies to solid walls of 200mm thickness or greater


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Celotex products to consider

1200 x 2400mm
0.022 W/mK

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