Aluminium
Types and Durability
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Description Aluminium (framing members) |
Expected Lifespan (Years) |
Adjustment Factors
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General
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| Extruded aluminium alloy sections to BS 1474. Anodized to BS 3987, minimum 25 micron coating. |
30 (10 years warranty for coating) |
1st stage adjustment factor:
In industrial areas (heavy polluted): -15% years In urban areas: -10% years In suburban areas: -0% years 2nd stage adjustment factor: Within 20m from express way: -20% years Within 20m from major arterial road: -10% years Within 20m from light traffic road: – 5% years Within 20m from sea water/ area prone to salt spray: -15% years Test certificate from approved local testing authority : +15% years |
| Extruded aluminium alloy sections to BS 1474. Liquid organic coating to BS 4842 after all fabrication, minimum 40 micron thickness. |
25 (10 years warranty for coating) |
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| Extruded aluminium alloy sections to BS 1474. Polyester powder coating to BS 6496 after all fabrication, minimum 40 micron thickness. |
25
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| Extruded aluminium alloy sections to BS 1474. Mill finished. |
15
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| Unclassified, ie aluminium alloy sections, not to BS 1474. |
< 15
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None
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Combination of adjustment factor (1st stage and 2nd stage) should be added to obtain the durability values. Refer to durability calculator.
Notes: The micron thickness should be measured in accordance with ASTM B 244-97 (2002) or equivalent.
For structural framing members, all extruded aluminium alloy should be fabricated from the most appropriate grade of alloy complying with BS EN 755. The aluminium extrusion should be designed in accordance with the guidelines given in BS 8118.
The life of metal coatings is influenced by the colour of the coating, the orientation of the building, and by the environmental conditions. Detailed guidance on lives and on any guarantee or warranty schemes is available from manufacturers. Proprietary products are available for the re-coating of factory applied coatings.