Every year, the United States experiences roughly 1,200 tornadoes, many across the Great Plains where dry air from the Rockies collides with humid Gulf air, spawning violent storms. In recent decades, however, the geography of risk has expanded. Tornado activity has shifted eastward into states like Kentucky, Tennessee, and northern Alabama-regions historically less prepared for such hazards. Since 1980, the duration, frequency, and severity of Atlantic hurricanes have also increased, including more of the most powerful storms (Categories 4 and 5). Also, a recent study published in Nature found a fivefold increase in incidents of severe straight-line wind events (e.g., derechos).
Recent years have offered sobering reminders:
- In May 2024, a derecho struck Houston with winds near 100 mph, shattering thousands of windows, leaving over a million without power, and causing more than $1 billion in losses.
- In May 2025, an outbreak of tornadoes across the central U.S. produced multiple EF2–EF3 events, destroying homes and critical infrastructure.
- Just weeks later, a June 2025 derecho and tornado outbreak swept across the northern Plains into Canada, producing hurricane-force gusts above 120 mph and widespread power outages.
These events make clear that no community is immune. Architects must plan for stronger winds, shifting hazard zones, and cascading impacts on infrastructure and human safety.
Wind Loads and Building Performance
Unlike hazards such as floods or earthquakes that may occur only once in a building's lifespan, wind loads act continuously on building envelopes. Though most winds fall well below design thresholds, the persistence of these forces exposes weaknesses that can be magnified during extreme events.
Minimum Design Loads and Associated Criteria for Buildings and Other Structures (ASCE/SEI 7) standard remains the governing reference for wind design loads. Building envelope components are addressed as Components and Cladding in the standard. Understanding that wind loads on components and cladding are a function of many more parameters than wind speed, such as the building risk category (how essential is the building function?), the position of components on buildings, and local topography and wind obstructions. This understanding will help architects appreciate that each project will have unique design requirements to achieve wind resilience. For example, a building on a beachfront property or near the crest of a hill may be subject to higher overall wind loads than a building tucked among others in a dense urban environment, though wind tunnels created by other buildings may subject urban buildings to concentrated wind loads on portions of the structure.
The most recent edition of the standard, ASCE 7-22, incorporates updated climatology, refined pressure data for soffits and overhangs, and-for the first time-explicit tornado wind-load criteria. In the U. S., tornadoes account for more annual loss of life and damage to property than hurricanes and tropical storms. Nevertheless, excepting storm shelters and safe rooms, the full force of tornado winds are rarely considered in the design of structures. However, low-grade tornadoes and other wind events (microbursts or derechos) are more probable than catastrophic tornadoes (~97% of tornadoes are EF0 or EF1) and can be considered by architects in the design of common structures.
Design wind pressures vary dramatically across a building's surface, with corner and edge zones experiencing far higher suction forces. Failures often occur progressively: a ridge cap or flashing fails, redistributing loads to adjacent panels, leading to cascading loss. Understanding these dynamics is essential for architects to work with engineers in detailing resilient systems.
Strategies for Wind-Resilient Design
Wind resilience requires more than code compliance. With the failure points noted above in mind, architects can develop details and specifications to create wind- resilient building enclosures, improving performance through thoughtful design, specification, and oversight. These include:
1. Go Beyond Minimums
- Consider safety factors and redundancy in cladding and roof systems.
- Specify closer fastener or clip spacing at high-pressure zones rather than relying on maximum allowed distances.
2. Prioritize Detailing and Installation Quality
- Construction documents must clearly communicate critical anchoring, spacing, and edge conditions.
- Field inspections should verify compliance, as laboratory test values often exceed real-world performance after aging and weathering impacts.
3. Choose Durable Materials
- Select components resistant to UV, moisture, and thermal degradation so they retain strength over decades.
- Favor systems with demonstrated long-term performance under cyclic loads.
4. Plan for Regular Maintenance
- Encourage owners to conduct periodic inspections of roofs and cladding.
- Minor leaks or performance issues in sub-design winds may indicate vulnerabilities that could lead to catastrophic failures during major events.
5. Retrofit for Risk Reduction
- In existing buildings, reinforce roof-to-wall connections, upgrade windows and doors to impact-rated assemblies, and improve anchoring of cladding.
- Retrofit measures are often cost-effective compared to post-disaster repairs and can reduce insurance premiums.
The Cost of Failure vs. the Value of Resilience
When building envelopes fail under wind pressure, the consequences go beyond material damage. Flying debris endangers lives. Rain intrusion compromises interiors and mechanical systems. Business continuity is disrupted. And after large-scale wind events, shortages of labor and materials delay recovery and inflate costs.
On the other hand, designing with resilience in mind has tangible benefits. Programs such as the Insurance Institute for Business and Home Safety's (IBHS) Fortified standard have demonstrated dramatic reductions in claims and damage costs. Projects built or retrofitted to these higher standards may also qualify for reduced insurance premiums, providing long-term savings.
A Standard of Care for Architects
The American Institute of Architects now recognizes resilience as part of the architect's evolving standard of care. Meeting minimum codes is no longer sufficient in the face of intensifying hazards.
Architects must:
- Understand the wind hazards specific to each project site, including tornadoes, hurricanes, derechos, and localized microbursts.
- Apply the latest design standards and integrate research findings into detailing.
- Collaborate across disciplines to achieve robust, buildable solutions.
- Communicate clearly with contractors and clients about the importance of installation quality and maintenance.
Building for Tomorrow's Winds
The rising frequency and severity of wind events, from derechos to tornado outbreaks, is a call to action. Architects have the tools and knowledge to create buildings that safeguard occupants, preserve investments, and support community resilience.
By exceeding minimum standards, specifying durable systems, and planning for long-term performance, architects can ensure that their projects stand strong when the next storm arrives. Preparedness Month reminds us: resilience is not added after disaster strikes-it is designed from the start.
Alan Scott, FAIA, LEED Fellow, LEED AP BD+C, O+M, WELL AP, CEM, is an architect and consultant with over 36 years of experience in sustainable building design. He is Director of Sustainability with Intertek Building Science Solutions.
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Alan Scott FAIA
Intertek, Building Science Solutions
Portland OR
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