All buildings, including Metal Building Systems, must be engineered to meet certain building code and load requirements defined by the municipality or jurisdiction in which the building is located. At Norsteel, all of our buildings are custom-made to order so that our certified engineers can design a building that accommodates your design requirements while still adhering to your local building code and load requirements.
What Are Building Codes and Loads?
Buildings provide shelter for people and property. While a building should have many desirable characteristics, including an attractive appearance, long life, flexibility of use and economy, its basic requirement must be one of protection.
To break this down even further, we can consider two kinds of protection that buildings provide:
1. Protection Against Forces or Loads that may be Exerted upon the Building
Unless the structure can offer adequate resistance against various loading conditions, the safety of people and the value of property are endangered. This is where sound design considerations must be given as to the strength of the building and particularly, to the structural system.
2. Protection Against the Elements – Rain, Wind, Heat and Cold:
Any of these can contribute to personal discomfort and cause a decrease in the value of contents and property. The degree of protection against the elements is determined by the weather tightness and thermal efficiency of a building. These factors greatly influence the design of a structure’s roof and walls.
Who Determines Building Codes and Loads
Building Codes and Loads are determined Nationally and Internationally, and imposed by our local municipal permit offices. When we design a structure, we use the job site location, specifically the postal code, to determine the applicable building codes and load requirements for that municipality. There are also considerations that may be specific to your exact site and how the building will be positioned on it.
Steel Building Load Calculations: Why They Matter
Before any steel building is manufactured or delivered, certified engineers must calculate the total loads the structure will need to support. These calculations ensure the building can safely withstand the combined effects of permanent, temporary, and environmental loads specific to its location and intended use.
Steel building load calculation is governed by local and national building codes. Engineers assess how the structure must respond to different types of forces—such as dead loads, live loads, collateral systems, snow, wind, and seismic activity. These forces are measured in pounds per square foot (PSF) and applied using advanced structural analysis tools and engineering standards.
Typical Load Values
Here are examples of common load values considered in steel building design:
| Load Type | Typical Range (PSF) |
|---|---|
|
Dead Load |
2 – 10 psf (structure’s own weight) |
|
Live Load |
20 – 40 psf (workers, equipment, temporary use) |
|
Collateral Load |
2 – 10 psf (lighting, HVAC, insulation, etc.) |
|
Snow Load |
20 – 120+ psf (depending on location and snow severity) |
|
Wind Load |
Varies based on wind speed, exposure, and building height |
How Loads Are Combined
Structural engineers do not consider loads in isolation. Instead, they follow load combination formulas defined by the building code, such as ASCE 7 in the U.S. or the National Building Code of Canada (NBC), to ensure the structure performs safely under a variety of conditions.
Some examples of common load combinations include (SkyCiv):
- 1.4 × Dead Load
- 1.2 × Dead Load + 1.6 × Live Load
- 1.2 × Dead Load + 1.6 × Wind Load + 0.5 × Live Load
- 0.9 × Dead Load + 1.0 × Wind Load (for uplift scenarios)
These combinations help engineers simulate how the building will respond to simultaneous forces, such as wind during a snowstorm or the weight of equipment during high occupancy.
Why Accuracy Matters
Incorrect load assumptions, whether underestimated or based on the wrong geographic zone, can lead to structural failure, costly redesigns, or permit rejections. Even small differences in assumed snow load or wind exposure can affect:
- Column and rafter sizing
- Foundation and anchor bolt requirements
- Bracing systems
- Overall stability under extreme conditions
For example, a building designed for southern Ontario will not perform the same in Nunavut unless it is re-engineered to account for the significant difference in snow and wind loads.
Structural Loads in Metal Buildings
Dead Load
The Dead Load is the total weight of the metal building system, including elements like the roof, framing, insulation, and covering members. The specific and detailed distribution of a structure’s weight must be taken into consideration when designing a building so that the structural integrity of the building itself isn’t compromised.
Live Load
The Live Load refers to any temporary load imposed on a building (that is not wind load, snow load, seismic load or dead load), that will be present during construction, maintenance, or present at different points throughout the life of the building. A few examples of a live load are workers, equipment and materials. The minimum Live Load per code is 20.89 PSF.
Collateral Load
The Collateral Load refers to the weight of additional permanent materials, other than the weight of the metal building system, such as sprinklers, mechanical and electrical systems, and ceilings. Collateral loads in a building are evenly distributed suspended loads inside the building. A normal (minimum) collateral load is 2 PSF, which takes into consideration roof insulation and normal lighting. Sprinkler systems add 3 to 4 PSF, suspended ceilings add another 4 PSF, and solar panels add 9 PSF.
At Norsteel we design all structures with a minimum collateral load of 3 PSF. In collateral load metal buildings, lowering this value might reduce upfront costs, but the long-term expense of reinforcing the structure after fabrication and erection typically outweighs the savings. The collateral load should be clearly indicated on costing sheets.
Concentrated or Point Loads
Concentrated Loads occur either from roof top units or are loads that are suspended inside the building. Roof top units are typically things like air conditioners and make-up air units. Suspended loads can be from heaters, ductwork, cable trays or support strapping, basketball nets, mechanical piping, suspended walkways or conveyors, roof top units. All concentrated loads need to be considered in the building’s design. Although they are technically dynamic live loads (e.g., cranes and material handling systems), Auxiliary Loads also fall under this category and must be given careful consideration in the design of the structure.
Environmental Loads
Wind Load
Structures must be designed to resist the wind load on metal building, which can come from any direction. There are 3 specific concerns to be aware of regarding wind: Speed, Exposure and Enclosure.
1. Wind Speed
Wind speeds vary greatly depending on a building’s physical location and surrounding geographic area. As a result, these loads are imposed by the steel building codes for the building site within the designated municipality.
2. Wind Exposure
Wind exposure is determined by the specific location of the structure itself on the site, and what features are near the building.
- Obstructions: Trees, buildings, terrain features
- Exposure B: Obstructions within ½ mile zone
- Exposure C: No obstructions on any side within ½ mile zone
3. Wind Enclosure
Wind enclosure speaks to the effect of wind as determined by the openings on the building itself.
- Enclosed: All openings can be relied on to be closed during a storm
- Partially Enclosed: One wall more open than the sum of the others; creates a ballooning effect
- Open: Buildings with all walls at least 80% open; openings will remain open during storms
Snow Load
Technically speaking, the metal building snow load refers to and addresses the vertical load induced by the weight of snow, assumed to act on the horizontal projection of the roof of the structure. This environmental load varies greatly depending on locality and site conditions. Note: Very wet snow 6” deep is equal to one inch of water. One inch of water on a square foot of surface weighs five pounds.
Seismic Load
The load or loads acting in any direction on a structural system due to the action of an earthquake.
While often associated with regions like British Columbia, seismic activity is not limited to mountainous areas—coastal regions can also be seismically active due to underwater fault lines and shifting oceanic plates. These seismic movements generate vibrations that travel inland and must be accounted for in building design.
In Canada, seismic risk was historically categorized into zones 0 to 6, but the current National Building Code of Canada (NBCC 2020) now relies on site-specific spectral acceleration values, calculated using tools like CanadaSHM6 and SHT2020. These tools allow engineers to design based on precise local data, rather than general zones (NRCan, 2023; SkyCiv, 2023).
In the United States, the IBC and ASCE 7 standards define Seismic Design Categories (SDC) from A to F, with Category A representing the lowest risk and F the highest. The classification is determined by seismic hazard, soil conditions, and building occupancy. Buildings in higher-risk areas must meet stricter design requirements to ensure safety.
Structural Steel Building Codes: Factors by Location
Building code requirements and structural design loads vary significantly based on where the building will be located. Local conditions such as climate, elevation, proximity to water, and surrounding terrain all influence the load values and code provisions used in a steel building’s engineering.
Geographic and environmental conditions across Canada and the U.S. play a major role in how structural steel buildings are designed. Below are some of the key factors that influence code requirements and load calculations by region.
Coastal vs Inland
Coastal regions are often subject to higher wind speeds, storm surges, and hurricane conditions. As a result, buildings in coastal zones must be designed with enhanced wind resistance and may require reinforced framing, additional bracing, and upgraded anchoring systems. In addition, designers may also consider material selection and protective coatings to mitigate the risk of corrosion caused by salt-laden air in marine environments.
Although coastal zones are primarily associated with wind and corrosion, many of these areas are also classified as high-risk seismic regions. Oceanic plate movement, current-induced vibrations, and proximity to fault lines can trigger seismic activity that must be accounted for in engineering.
In contrast, inland locations typically have more stable wind conditions but may face different challenges such as higher snow loads or seismic activity depending on the region. Load values and exposure categories vary widely between these two geographic contexts, even within the same province or state.
Rural vs Urban Exposure
The immediate surroundings of the building site also impact how wind loads are calculated. Building codes classify sites by exposure categories (B, C, or D), based on the degree of wind obstruction.
- Urban or suburban areas (Exposure B) often have nearby buildings, trees, and structures that reduce wind pressure on the building.
- Rural and open areas (Exposure C) lack obstructions, meaning wind loads are higher and buildings must be engineered to withstand more direct pressure.
- In very flat, open terrain near large bodies of water (Exposure D), even more conservative wind load values may be required.
This classification significantly impacts the required steel design and connections, particularly for larger buildings or open-span structures.
Wind and Snow Zones in Canada/US
Snow and wind loads vary by region and are prescribed by national building codes, such as the National Building Code of Canada (NBCC) and the International Building Code (IBC) in the U.S.
- In eastern and northern Canada, snow loads are typically much higher due to longer winters and greater accumulation. Some regions may require snow loads of 60 PSF or more.
- In parts of the U.S., snow loads can also be high, especially in the northern Midwest, Northeast, and mountain states.
- Wind zones are elevated in coastal areas (e.g., Nova Scotia, Florida, the Gulf Coast), where hurricane-force winds are expected.
- Certain inland regions, especially on the U.S. plains or in parts of Alberta and Saskatchewan, are also exposed to high wind speeds due to flat, unobstructed terrain.
This is why using site-specific data is essential when determining design loads. Generic assumptions can result in code violations, failed inspections, or compromised structural safety.
Building Code Compliance for Metal Buildings
Building code compliance means ensuring your structure meets the safety, structural, and environmental standards set by national and local regulations. We design our buildings to meet or exceed structural steel building codes, including IBC requirements, Canadian building codes, individual provincial codes, and CSA-A660 standards.
That is why it is crucial to work with a building supplier who understands and applies these standards from the very start. When pricing out your steel building, ensure that your building provider is asking the questions that are important in ensuring the integrity of your building and the safety of everything you will be protecting.
Remember that pre-engineered buildings are custom designed and manufactured to your specific requirements. Each component is carefully engineered to ensure that it can withstand the elements for your specific circumstance. This is why there are no genuine clearance buildings and why customers should be very weary of buying a building that was designed for someone else.
The design of your building relies on the information that you provide about its purpose, content and about the site itself. At Norsteel, regardless of a job’s location, we always demand a series of minimum requirements for our building projects to ensure a consistent level of quality construction.
Closing Out
The types of loads and their magnitudes are critically important to the design and construction of your steel building. At Norsteel we’ll work with you on your building project from start to finish to ensure the proper steel building codes and loads are used, without sacrificing the performance and functionality that you need. From commercial steel buildings, to agricultural, to even mining facilities, we do it all.
Click here to contact us today for a free quote on your next project!
