AS 1562.1:2018 pdf download.Design and installation of sheet roof and wall cladding Part 1: Metal.
SECTION 3 DESIGN
3.1 SCOPE
This Section sets out requirements for the design of cladding systems comprising cladding, and cladding fasteners.
NOTES: I Guidance on roof ventilation is given in Appendix A. 2 Guidance on water penetration is given in Appendix B. 3 This Section requires the specification of the supporting members in order to define the capacity of the cladding fasteners, but the scope of this Section does not cover the design of the supporting members themselves. 4 Cladding systems are not normally designed to carry additional loads from accessories fixed directly to the cladding, e.g. air-conditioning units, vents or antennas. If these are to be fixed directly to the cladding then the capacity of the cladding to carry these loads should be verified.
3.2 LOADING
3.2.1 General
The cladding and its fastenings to the supporting member shall be designed to withstand the loads derived from the actions specified in AS/NZS 1170.1, AS/NZS 1170.2 and AS/NZS 1170.3, when combined in accordance with the load combinations in AS/NZS 11 70.0, for the particular circumstances in which the cladding and fastening system will be used.
Materials and installation specifications shall achieve resistance to the loads and actions identified in this Clause (3.2) and shall be recorded in design documentation as specified in Clause 3.5.
3.2.2 Imposed actions
Imposed actions shall be appropriate for the roof categories defined in AS/NZS 1170. 1. For roof category R2, the design documentation (see Clause 3.5) shall clearly identify whether the roof is designed for either one of the following: (a) Cladding providing direct support and that persons may walk or stand anywhere on the roof without causing damage to the sheet.
(b) Cladding over which boards or ladders are required to be laid, and including indication of— (i) the positions on the roof sheet on which a person may walk or stand without causing damage to the sheet; (ii) temporary walkways that are to be provided for access; or (iii) the marking of roofing with a visible sign or sticker with the warning ‘FOOT TRAFFIC IS NOT ALLOWED’.
3.2.3 Wind actions
Local pressure factors defined in AS/NZS 1170.2 or edge region pressures defined in AS 4055 shall be applied to the external pressures for cladding system at edges, ridges and corners of building roofs and walls.
3.2.4 Snow and ice action
Design for loads from the accumulation of snow shall conform to AS/NZS 1170.3. NOTE: AS/NZS 1170.3 does not address loads from hail.
3.2.5 Lateral restraint
Cladding is buckling, in available for not considered to be efficient restraint for supporting structures against particular cold-formed steel purlins, unless experimental (test) data are cladding assemblies including cladding, its fixings and supporting structures.
3.2.6 Thermally induced movement or loadings Thermally induced effects shall be accommodated by either— (a) demonstrating that the system can resist the applied thermal loads; or
NOTE: This may be achieved by limiting maximum length between top and bottom rows of fasteners on a sheet. (b) detailing the system to absorb the applied thermal movement.
NOTE: Absorbtion of applied thermal movements may be achieved by the— (a) provision of expansion joints; and/or (b) use of elongated slots on sheets. NOTES: 1 Appendix C provides guidance on typical coefficients of linear expansion. 2 To give an indication of the extent of thermal expansion that unrestrained 15 m steel sheet expands through approximately 24 mm for a temperature variation from 0°C to 65°C. In practice, may be less than this due to many factors including friction and structure. needs to be considered, an 12 mm and aluminium for cladding movement in roofs flexibility of the supporting. 3 Practical demonstration of bracing capacity of the sheeting may be required for systems with provision for accommodating thermal induced movement (see Appendix E). 4 Transverse thermal expansion in ribbed cladding is absorbed by lateral distortion of the ribs.
3.3 ROOF DRAINAGE
3.3.1 General
The cladding system shall provide water resistance and drainage when subjected to a rainfall resulting from a storm having an average recurrence interval of 100 years as determined in accordance with AS/NZS 3500.3 or local meteorological data. NOTE: Roof drainage is affected by— (a) the length and pitch (i.e. slope) of the roof; (b) the profile of the cladding and its water channel drainage capacity; (c) the risk of ponding in the case of a low pitch roof; (d) anti-capillary feature geometry and location design on side laps; (e) the potential penetration of water through end and side laps; (f) drainage from an upper roof to a lower roof; (g) change of pitch or a concave roof leading to a transition from laminar to turbulent flow; (h) any penetrations in the roof that affect the flow of water down the roof pitch; and (I) deflection of a roof structure will alter the roof pitch; the initial pitch, which therefore, should include an allowance for any permanent deflection of the roof structure, in particular long-term deflections in timber-framed structures.AS 1562.1 pdf free download.