SIST EN 1999-1-4:2007/A1:2012

SIST EN 1999-1-4:2007/A1:2012 is the Slovenian standard for Amendment A1 to Eurocode 9, Part 1-4, published by SIST. It modifies the rules for cold-formed structural sheeting in aluminium structures, with a focus on material data in Table 3.1. Engineers, fabricators, constructors, and specifiers use it when they need the amended alloy information and the related guidance for design and procurement.

What does SIST EN 1999-1-4:2007/A1:2012 specify?

SIST EN 1999-1-4:2007/A1:2012 specifies a change to EN 1999-1-4:2007 rather than a full rewrite. The parent standard gives design requirements for cold-formed trapezoidal aluminium sheeting and for stressed-skin design using aluminium sheeting as a structural diaphragm.

The parent standard applies to aluminium products made from hot rolled or cold rolled sheet or strip that have been cold-formed, for example by cold-rolled forming or press-breaking. It also states that the execution of aluminium structures made of cold-formed sheeting is covered in EN 1090-3.

It excludes cold-formed aluminium profiles such as C- and Z-profiles, and cold-formed and welded circular or rectangular hollow sections. It covers both design by calculation and design assisted by testing, with calculation methods limited to stated ranges of material and geometric properties.

The amendment is organized with a foreword and one technical clause that modifies 3.1, mainly through Table 3.1 and its note.

What are the key requirements of SIST EN 1999-1-4:2007/A1:2012?

• Clause 1, point (1) sets the scope of the parent standard for cold-formed trapezoidal aluminium sheeting. In practice, this tells the designer what product form the rules are intended for before checking any resistance or stability rules.
• Clause 1, point (2) includes stressed-skin design using aluminium sheeting as a structural diaphragm. This matters when the sheeting is part of the load-resisting system, not only a covering.
• Clause 1, point (3) excludes C-, Z- and similar profiles, as well as welded circular or rectangular hollow sections. That helps users avoid applying the sheeting rules to the wrong aluminium product.
• Clause 1, point (4) allows both calculation and testing, but the calculation methods are only valid within stated material and geometry ranges. In practice, outside those ranges the document points users toward design assisted by testing.
• Clause 1, point (5) states that load arrangement for loads during execution and maintenance is not covered. This means temporary load cases still need separate project or contract rules.
• Clause 1, Table 3.1 changes one alloy designation from AlMg2 to AlMg2Mn0,3. For users, this is a material-data correction that affects selection and specification.
• Clause 1, Table 3.1 and footnote 6 add EN AW-6025-7072 alclad and describe it as a composite with EN AW-6025 core and EN AW-7072 cladding on both sides. The note says the cladding should be at least 4% of total thickness on each side for durability, and if cladding exceeds 5% it should be considered in structural calculations by taking only the core thickness into account.
• Footnote 6 also says the minimum cladding thickness and minimum core thickness should be stated in the execution specification so the constructor can procure products with inspection certificate 3.1. In practice, that links design assumptions to purchasing and verification documents.

What terms does SIST EN 1999-1-4:2007/A1:2012 define?

• Cold-formed structural sheeting - Aluminium sheeting formed from sheet or strip by cold forming or press-breaking for structural use.
• Stressed-skin design - A design approach where the sheeting acts as a structural diaphragm and contributes to load transfer.
• Structural diaphragm - A sheet element that helps carry in-plane forces through the structure.
• Alclad - A composite aluminium material with a core and cladding layers on both sides.
• Execution specification - The document where the required cladding and core thicknesses are stated for procurement and fabrication.
• Inspection certificate 3.1 - The certificate identified in the note for constituent products supplied for the composite sheet.

Who uses SIST EN 1999-1-4:2007/A1:2012?

SIST EN 1999-1-4:2007/A1:2012 is used by structural engineers, designers, and checking authorities working on aluminium roof and wall sheeting, or on sheeting used as a diaphragm. Fabricators and constructors use it when they need the material designation and thickness guidance for EN AW-6025-7072 alclad. Procurement and quality teams use it to align ordering, inspection, and execution documents with the specified material makeup.

What changed in SIST EN 1999-1-4:2007/A1:2012 from the previous edition?

SIST EN 1999-1-4:2007/A1:2012 replaces SIST EN 1999-1-4:2007 and is identical to EN 1999-1-4:2007/A1:2011. The amendment updates Table 3.1 by replacing AlMg2 with AlMg2Mn0,3, adding EN AW-6025-7072 alclad, and adding a note on cladding thickness, core thickness, structural calculation, and inspection certificate 3.1.

Which standards are used with SIST EN 1999-1-4:2007/A1:2012?

EN 1090-3 is the execution standard named in the scope for aluminium structures made of cold-formed sheeting. EN 1999-1-4 also says its rules complement the other parts of EN 1999-1, so it is meant to be used alongside the rest of the Eurocode 9 series.

What does the SIST EN 1999-1-4:2007/A1:2012 document contain?

The document contains a foreword, a contents page, and one technical clause that modifies 3.1. Its main technical content is Table 3.1, where alloy data are revised and a new alclad material entry is added. The added footnote explains the composite construction of EN AW-6025-7072 alclad and how cladding thickness affects design and procurement. In practice, the document is used for material selection, structural design checks, and specification writing for cold-formed aluminium sheeting.