Engineering & Design
Design Codes for Pre-Engineered Buildings Worldwide
Design codes for pre-engineered buildings are the building regulations and referenced standards that set the loads a metal building must resist, the rules for designing its hot-rolled, built-up and cold-formed steel members, and the requirements for welding, bolting, fabrication and erection in the country where it is built.
Key facts
- The building code of the project location governs, not the code the supplier is most familiar with.
- Each code family separates loads, member design, connections and fabrication into different documents.
- Primary frames follow structural steel standards; purlins, girts and panels follow cold-formed steel standards.
- National annexes or local amendments can change values and methods inside the same code family.
- World Steel designs PEB structures to the code specified for the project, including US, Canadian, Australian/NZ and European codes.
Why the governing code is fixed by the project location
A pre-engineered building is regulated exactly like any other structure. The authority having jurisdiction at the site adopts a building code, and that code calls up the loading, steel design and fabrication standards the engineer must use. A building manufactured in one country and erected in another is designed to the rules of the destination.
For this reason the first line of any PEB enquiry should name the governing building code, its edition and any local amendments. Changing the code after design has started usually changes snow, wind and seismic loads, which in turn changes frame sizes, bracing and anchor bolts.
How United States codes approach metal buildings
In the United States most jurisdictions adopt the International Building Code (IBC). The IBC refers to ASCE 7, Minimum Design Loads and Associated Criteria for Buildings and Other Structures, for dead, live, snow, wind, rain and seismic loads. Steel members and connections are designed to AISC 360, Specification for Structural Steel Buildings, with AISC 341 Seismic Provisions where the seismic design category requires it.
Cold-formed purlins, girts and panels are designed to AISI S100, the North American Specification for the Design of Cold-Formed Steel Structural Members. Welding follows AWS D1.1, bolting follows the RCSC Specification for Structural Joints, and materials are specified by ASTM standards. The MBMA Metal Building Systems Manual is widely used as industry guidance on loading and practice specific to metal buildings.
How Canadian codes approach metal buildings
Canada uses the National Building Code of Canada (NBCC), adopted with or without changes by each province and territory. Part 4 of the NBCC sets the loads and the limit states design framework, including climatic data for snow and wind at named locations.
Steel members are designed to CSA S16, Design of Steel Structures, and cold-formed members to CSA S136, the Canadian edition of the North American cold-formed specification. Welding follows CSA W59, and CSA W47.1 sets requirements for companies that weld structural steel. CSA A660 is the Canadian standard for certification of manufacturers of steel building systems and is often referenced in project specifications.
How Australian and New Zealand codes approach metal buildings
In Australia the National Construction Code calls up the AS/NZS 1170 series for structural actions, covering permanent and imposed actions, wind actions and, in Australia, earthquake actions through AS 1170.4. New Zealand uses the same series, with NZS 1170.5 for earthquake actions and its own Building Code compliance documents.
Steel structures are designed to AS 4100 in Australia, while New Zealand applies NZS 3404. Cold-formed members follow AS/NZS 4600, welding follows AS/NZS 1554.1, and AS/NZS 5131 covers fabrication and erection of structural steelwork. Coated sheet for purlins and cladding is commonly specified to AS 1397.
How European codes approach metal buildings
Across Europe the Eurocodes form a common framework. EN 1990 sets the basis of structural design and load combinations, EN 1991 defines actions such as snow and wind, and EN 1993 covers steel design, with EN 1993-1-3 dedicated to cold-formed members and sheeting. Each country publishes a National Annex that fixes nationally determined parameters, so a design for one member state cannot simply be reused in another.
Execution of steel structures is governed by EN 1090, which links the required quality level to the consequence and service conditions of the building. Welding quality management is addressed by EN ISO 3834, and corrosion protection by EN ISO 12944 and EN ISO 1461.
Points to confirm with your engineer
- The building code and edition adopted at the site, with local amendments.
- The importance, risk or consequence class assigned to the building.
- Site climatic data for snow, wind and rain, and the source of that data.
- The seismic parameters and whether special seismic detailing applies.
- Which steel, cold-formed and welding standards the authority expects to see.
- Whether drawings must be sealed by an engineer registered in the jurisdiction.
Frequently Asked Questions
Can a pre-engineered building designed to US codes be erected in Europe or Australia?
Not without redesign. Loads, load combinations, resistance factors and material grades differ between code families, and the local authority will review the design against its own adopted code. The building must be designed to the code of the site from the start.
Is the MBMA manual a building code?
No. The MBMA Metal Building Systems Manual is industry guidance that explains how codes apply to metal buildings and offers recommended practice. The legally binding requirements come from the building code and the standards it references.
Which code does World Steel use?
We design to the code specified for the project, including US, Canadian, Australian/New Zealand and European codes. The project engineer confirms every design decision against the governing code and any local amendments.
Engineering content is general guidance. Every World Steel building is designed by qualified engineers to the code and loads of the project.
