BS EN 508-2:2009 pdf download – Roofing products from metal sheet — Specification for self supporting products of steel, aluminium or stainless steel sheet Part 2: Aluminium
Reverse side painting or coating is used if being required for handling and storage reasons as well as for corrosion protection in some installation conditions.
Performance and test methods for coil coated aluminium shall be in accordance with EN 1396.
NOTE 3 Special coatings or films may be applied to the reverse side to reduce the dripping of moisture caused by condensation.
4.3.1 Mechanical resistance
The product shall resist the design loads from snow, wind and maintenance. These loads shall be factored such that they will not impair the performance of the roof.
NOTE The load level, the levels of safety and permissible deflection are defined in national building regulations.
4.3.2 Calculation and tests of mechanical resistance
The mechanical performance of the product shall be stated by the manufacturer, together with details of how the values were determined in accordance with the national regulations of the country where the product is to be used.
NOTE 1 For calculation and testing either national regulations or EN 1999-1-4 may be used.
NOTE 2 Calculation and test methods referred to in this EN mainly deal with trapezoidal sheets. Tiles, standing seam sheets and concealed fix sheets are used in proprietary roofing systems, no structural requirements are given within this standard for these products. These products should normally be designed by testing.
The dimensions of the product shall be fixed in order that the roof constructed with these products can fulfil its functions.
Measurements of the thickness of manufactured products such as profiled sheets shall be made not less than 10 mm from the edges in accordance with EN 485-4.
Products shall be classified according to tolerance on thickness as follows:
class 1: full minus nominal normal tolerance according to EN 485-4;
class 2: 1/2 minus nominal normal tolerance according to EN 485-4;
class 3: zero minus tolerance.
NOTE 1 For products of class 3, mechanical resistance is calculated using the minimum thickness of the aluminium core guaranteed by the manufacturer.
NOTE 2 National regulations will state the class of product that it will be possible to use.
4.3.4 Dimensional tolerances for the profiled sheet
Tolerances for the profile shape of the product and methods of measurement shall be in accordance with Annex B.
4.3.5 Safety in case of fire
Until the withdrawal of national technical specifications, products coated with organic coatings shall comply with these specifications.
NOTE 1 The withdrawal of national technical specifications will occur in the European Union at the end of the transitional period of EN 14782.
NOTE 2 Aluminium is non-combustible. It will not burn and will not support combustion. Its melting point is approximately 630 °C, so it will melt in an intense fire. It is essential that the effect of a fire is evaluated after studying the whole structure.
5 Test methods
5.1 Material properties
Test methods for material properties are given in the appropriate material standards as detailed in 4.2.
5.2 Surface properties
Test methods for surface properties are given in EN 1396.
5.3 Structural properties
The performance of the product under distributed load shall be determined in accordance with 4.3.1 and 4.3.2.
The performance of the product under concentrated load shall be quoted by the manufacturer with reference to the method used to determine the results.
NOTE Safety under the load from people and the risk of permanent deformation is dependent on many factors, such as slope of roof, method of installation, etc.
Methods for testing the strength under concentrated load are not yet available on a European level. Information on national standards is given in Annex C. Rules for installation are given in some national codes.
Products covered by this part of EN 508 shall be designated as follows:
type of product according to the designation of the manufacturer;
European standard number;
nominal thickness and thickness class (see 22.214.171.124);
material (designation of material) (see 3.5 and 4.2);
length of step (only for tiles).