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External wall insulation, the technology

Surface treatments facades: The substrate surface should be adhesive, clean, plain and without dust or mould.

Base Profile: Aluminium Base Bead is used to support the insulation boards above plinth level. This should be set in a perfect horizontal position.

Render: Lightweight mineral one-coat render. To be mixed with clean water, free of any impurities. Stored in dry conditions.

Insulation Boards: We recommend EPS lightweight polystyrene due to its longevity properties. The latest EPS-Graphite is 20% more efficient than the classic EPS 100, EPS 80 or EPS 70. Thickness will vary between 30mm and 200mm. Nominal density as low as 16-17 kg/mc. A solid minimum compressive strength of 80kn-m2.

The lighter the materials, the higher the longevity of the External Wall Insulation system. Light materials will adhere better to existing walls. Comprehensive strength helps durability as the material is more resistant. Durability is further aided by the final decorative coating.

Drip Beads: These are situated between the main insulation boards and the plinth. Drip Beads help divert rain water away from the foundations of the building.

Plinth Insulation Boards: XPS polystyrene. These should be thinner to allow for the Drip Beads. Should also be more resistant, to support the weight of the EWI system. Thickness between 20mm and 80 mm. Nominal density of 323kg/m3. Minimum compressive strength of 250 kN- m2.

Reinforcing mesh: The mesh is bedded into the render coat and will also aid durability. The mesh, if installed correctly, will prevent any cracks appearing in the future.

Mechanical fixings: The insulation boards are securely fixed using Glass Reinforced Plastic (GRP) fixings.

Decorative Coating: The coating gives a high quality finish. It also aids durability. This is a breathable membrane, which means damp will never be a problem again. Any stains or dirt marks can easily be removed with water and a brush.


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