Code: 22504

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Polyfoam Cavityboard

Product Description

For thermal insulation of masonry cavity walls

Description

Polyfoam Cavityboard is a high performance, 100% ozone friendly, extruded polystyrene, rigid board insulation. It is lightweight, yet has excellent rigidity and long term effectiveness, even when exposed to moisture. Polyfoam Cavityboard is supplied with interlocking rebated edges that help to create a complete insulated envelope with fewer gaps and also help to restrict moisture ingress across the finished construction.

Application

Polyfoam Cavityboard is used for the insulation of partial fill cavity walls or external wall insulation as part of a cladding/render finish. In wall insulation, the optimum solution has to:

be practical and simple to install
have rebated edges to give the maximum wall coverage
perform correctly if exposed to water during installation or in application (damp cavities or damp walls should not impact performance)
be a good thermal performer
be stable in the long term

The following range of applications are the key areas of use of Polyfoam Cavityboard:

Housing
Offices
Schools
Hospitals
Retail developments
Public buildings

Polyfoam Cavityboard is recommended for the following wall constructions:

Partial Fill Cavity Wall insulation in new build
External wall insulation in new build or refurbishment

Note: Our recommended solution for full fill cavity walls is Crown DriTherm- please contact our Technical Support team for more information.

Performance

Compression resistance
The rigidity of Polyfoam Cavityboard makes the board easy to handle and less prone to site damage than less robust materials. In external render systems the rigidity of the Polyfoam board behind the metal lath and render will offer an excellent support to the lath and assist in the resistance of impact, helping to prolong its service life.

Moisture resistance
As can be seen in the attached detail drawings. Polyfoam Cavityboard can be used to insulate foundation walls below dpc level. The boards are resistant to moisture absorption and can be laid in ground water or up against wet concrete with minimal impact on the performance of the product. The interlocking rebated edge sheds any water into the cavity away from the inner leaf in the unlikely event that it penetrates the gap between two boards.

Thermal insulation
Polyfoam Cavityboard is a high performance insulant, with aged quoted thermal performance values which are virtually unaffected by moisture on site. The actual performance in use of Polyfoam Cavityboard with the numerous potential block and internal finish options is outlined in the attached U-Value tables.

Fire Performance
Polyfoam Cavityboard contains a flame retardant to inhibit localised ignition. The use of Polyfoam Cavityboard will not prejudice the fire resistance of the wall.

Certification

Polyfoam Cavityboard is 3rd party certified by the British Board of Agrément.

Handling and storage

Polyfoam Cavityboard is supplied in polythene packs, labelled with identifying product and manufacturing data. The boards are easy to handle and nonirritant, no special protective clothing is required to install them. Polyfoam products should not be left exposed to prolonged sunlight as this will result in surface degradation. Where outside storage for extended periods is required cover with opaque/light coloured sheeting. Ensure the boards are not stored close to open flame or other ignition source, also avoiding volatile compounds and chemicals such as solvents