BS EN 508-2 pdf free download

BS EN 508-2-2019 pdf free download.Roofing and cladding products from metal sheet – Specification for self-supporting products of steel, aluminium or stainless steel sheet Part 2: Aluminium.
4.3.1 Mechanical resistance
The product for roof shall resist the design loads from self-weight, insulation (if applicable), eventual membranes, snow, wind and maintenance. These loads shall be factored such that they will not impair the performance of the roof. The load level, the levels of safety and permissible deflection are defined in national building regulations.
The product for cladding shall resist the design loads from self-weight, eventual insulation and wind.
These loads shall be factored such that they will not impair the performance of the roof. 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.
For calculation and testing either national regulations or EN 1999-1-4 may be used.
Calculation and test methods referred to in this standard mainly deal with trapezoidal sheets. Tiles, standing seam sheets and concealed fix sheets are used in proprietary roofing and cladding systems, no structural requirements are given within this standard for these products. These products should normally be designed by testing.
4.3.3 Dimensions
4.3.3.1 General
The dimensions of the product shall be fixed in order that the roof constructed with these products can fulfil its functions.
4.3.3.2 Thickness
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 provided 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
4.3.5.1 General
Aluminium is non-combustible. It will not burn and will not support combustion. Its melting point is approximately 630 °C. As a result it will melt in an intense fire. It is essential that the effect of a fire is evaluated after studying the whole structure.
4.3.5.2 Reaction to fire
The performance shall be defined according to Euroclass system. EN 14782 defines the Single Burning
Item (SBI) specimen when required, including direct and extended application rules.
NOTE National regulations fix the reaction to fire level required for the different building types.
Non-organically coated products are considered to satisfy the requirements for performance Class A1 of the characteristic reaction to fire in accordance with the provisions of EC Decision 96/603, as amended, without the need for testing.
Products with a polyester coating having a maximum nominal thickness of 25 μm and a PCS up to 1 MJ/m 2 (included) or a mass ≤ 70 g/m 2 are considered to satisfy the requirements for reaction to fire performance Class A1 without further testing in accordance with Commission decision 2010/737/EC.
4.3.5.3 External fire roof performance
When required, the performance shall be defined according to the euroclass system.
NOTE The external fire roof performance can be Broof t1, Broof t2, Broof t3 or Broof t4.
5 Test methods
5.1 Material properties
Test methods for material properties are given in the appropriate material standards as detailed in 4.2.BS EN 508-2 pdf download.