Engineering Access: Designing Structural Openings in Metal Buildings For High-Traffic Use

by David Flaherty | 17 December 2025 10:41 am

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Metal is gaining popularity as a primary building material. It can sustain high loads and extreme weather conditions with a low risk of bending, breaking, or collapsing. Openings, such as doors and windows, are critical components of effective building design, but they also pose obstacles that designers must overcome. By evaluating these factors, construction professionals can follow best practices to maintain structural integrity and safety while preserving function and aesthetic appearance.

Understanding material properties

The type of material and its properties dictate how designers can create openings. Although numerous building materials are commonly used in high-traffic commercial buildings, steel is often preferred due to its strength, durability, and other desirable features. When using steel or another metal for construction, professionals must select the right grade. Specific grades are more likely to maintain strength under high load-bearing conditions, while others can provide weather resistance or durability despite chemical exposure. The addition of corrosion-resistant coatings or stainless steel can better ensure longevity.

Optimize space and function

The primary objective of metal construction is to optimize a building for both space and function. While openings create structural challenges that building professionals must overcome, they must also fit with the overall design of the building. Openings should meet the key needs of the space while minimizing obstructions and other hurdles to entry or exit from the building. Employing good design practices, such as large, clear spans or efficient mechanical access, can result in a structure that achieves its primary goals.

Balance aesthetic and function

Aesthetics is a notable advantage of metal buildings, but effort must be made to ensure the structure remains structurally sound and functional. The use of exposed metal is a trending design feature in commercial and residential buildings, but with some limitations. Specifically, metal is more likely to corrode due to weather or chemical exposure, and it contributes to higher heat transfer. These factors can create unsightly views of the building, weaken its structural integrity, or reduce its overall efficiency. Aesthetic designs in openings should prioritize the primary function of the space while maintaining structural integrity over time.

Maintain structural integrity

The governing aspects of structural building design prioritize integrity highly. For the building to fulfill its primary function, it must be able to withstand weather and other factors without compromising its strength or risking collapse. Structural integrity requires several considerations, including:

• Strength-to-weight ratio of chosen materials.
• Load and force calculations.
• Framing and bracing options.
• Exposure to precipitation, wind, and chemicals.

Even minor decisions can have a significant impact on the longevity of the building. Design professionals should evaluate the building when tailoring designs and choosing materials for openings.

Manage load distribution

To ensure the opening can support the weight from above without collapsing, a comprehensive load calculation is necessary. Loads are estimated in a few ways, such as:

• Live loads: Weight including occupants, equipment, supplies, and more.
• Dead loads: The weight of the structure itself without any other equipment or occupants
• Environmental loads: Weight resulting from weather, including snow, wind shear, or seismic activity.

When estimating loads, professionals need to perform load combinations that account for the various forces that impact structural integrity. The goal is to create a building that can withstand unusual or extreme situations.

Specify appropriate framing and bracing

Frame stability is a factor of load and force. The load comes from above, while lateral forces can push the building from the side. Portal frames and moment frame openings provide ideal scenarios where architectural professionals can create large openings for high use. To achieve these design aspects, proper bracing is key. Cross-bracing and cable bracing are often insufficient because they block the ability to install a doorway. Instead, designs such as moment frame openings use bolts to ensure high shear strength even for longer openings. Designers are concerned with shear walls and other building requirements for windows and doors, in addition to the need to comply with local building codes.

Promote fire protection

Metal is often the preferred building material for fire protection, but it has its limits. In particular, steel loses strength once interior temperatures reach more than 932°F.[2] If the metal is exposed for design or functional reasons, that exposure can additionally weaken it. Common approaches to improving fire protection include:

• Fire breaks between walls and around openings.
• Intumescent paint that expands rapidly due to rising heat.
• Concrete casing to protect the steel framing.

Proper design for openings can help ensure a fire in one part of the building is less likely to spread to other areas.

Ensure maintenance access

During and after construction, maintenance crews should be able to access various parts of the structure for upkeep and repair. Interior doorways should be wide enough for technicians and other professionals to enter and navigate large equipment, such as furnaces, water heaters, or industrial systems. Exterior doors, especially motorized options, should provide opportunities for maintenance teams to access the axle and other parts when they require repair. The use of prefabricated components, such as an electrical conduit[3], can provide a way to ensure proper construction while maintaining access to key services within the building.

Optimize insulation and weatherproofing

Since metal is highly conductive, adding insulation and weatherproofing is a critical consideration. In most cases, designers add thermal breaks to metal door and window framing. The choice of material for the opening affects its thermal performance. While metal is often more durable, it may require the use of thermal breaks to perform as well as vinyl or fiberglass. Thermal breaks create an interior and exterior aspect of each frame, which allows space in between to increase insulation and reduce heat transfer. Designing to minimize air leaks increases efficiency, although weatherstripping may be required in extreme weather situations.

Jim Nicketta is manufacturing and prefabrication Manager at DuFab Manufacturing, a prefabrication and modular construction company that helps clients tackle large construction projects. Nicketta oversees all operations and project needs, and is an integral part of the team.

SOURCES

https://havitsteelstructure.com/steel-structure-design/#6_Fire_and_Corrosion_Protection

https://peb.steelprogroup.com/steel-structure/components/adding-windows-doors/

https://havitsteelstructure.com/steel-structure-design/

https://ccpia.org/types-of-lateral-force-resisting-systems-in-commercial-buildings/

https://www.fortifybuildingsolutions.com/resources/blog/types-of-bracing-for-metal-buildings/

https://www.dawsonmetal.com/thermal-break

https://www.designingbuildings.co.uk/wiki/Structural_opening

https://strucalc.com/blog/learning/6-tips-to-take-your-work-from-good-to-great/

Source URL: https://www.metalconstructionnews.com/articles/structural-openings-metal-buildings/

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