Recent winter storms in the southern U.S. are revealing critical gaps in the design, construction, and maintenance of buildings for snow and ice loading conditions.
Key Takeaways
- Snow and ice accumulation can exceed assumed roof load capacities
- Code compliance does not always ensure resilient performance
- Design and construction deficiencies often remain hidden until extreme events
- Pre- and post-storm inspections are critical to reducing risk
Overview
A large-scale winter storm from January 23-27, 2026, impacted approximately two-thirds of the U.S., stretching more than 2,000 miles from Texas to New England. In parts of the South, including Arkansas, Mississippi, Tennessee, and Kentucky, snowfall was followed by prolonged freezing rain and sustained below-freezing temperatures.
This uncommon sequence created extended snow and ice accumulation on roofs for more than two weeks; loading conditions many buildings in these regions were not designed to withstand. The event exposed vulnerabilities in structural systems that are rarely tested in Southern climates.
How Buildings Are Designed for Snow Loads
Based on design codes, structures are designed to resist snow loads using two primary criteria. The first is serviceability. This ensures the building has sufficient stiffness to prevent excessive displacements, such as roof sagging or leaning columns, that could disrupt day-to-day operations (e.g., doors not operating properly, cracked finishes, displaced cladding, or sagging ceiling panels). The second is strength and safety. Structures must provide a continuous load path with adequate capacity to transfer snow loads from the roof to the foundation.
Where Design Standards Fall Short
Older code editions for design loads on roofs did not consider the loading scenario of increased loads as a result of rain-on-snow surcharge. Therefore, the back-to-back snow, ice, and freezing rain events combined with below-freezing temperatures during the January 2026 event created loading conditions that were not considered in older code editions—meaning some older buildings were not designed to resist them. In these cases, real-world conditions exceeded design assumptions.
How Buildings Respond to Snow and Ice
Heavy snow and ice accumulation can cause varying levels of damage, particularly in regions where such conditions are infrequent.
Damage typically falls into three categories:
Slight Damage
- Minor roof deflection and slight ceiling sagging
- Small cracks in interior wall and ceiling finishes
- Typically recoverable after snow/ice melts
- May require minor nonstructural repairs
- Structural strengthening may be considered for future events
Moderate Damage
- Noticeable sagging of roof framing members
- Leaning walls or columns
- Larger cracks in finishes and exterior cladding
- Doors and openings may become misaligned (“sticky doors”)
- Some deformation may be permanent
- Typically requires structural repair, including:
- Member or connection replacement
- Additional reinforcement
Severe Damage
- Significant permanent deformation of structural members
- Twisting of joists or buckling of trusses
- Connection failures or fractures in steel/wood members
- Fastener pullout
- Partial or complete roof collapse
What We Observed in the Field
The failure cases we investigated with our clients revealed not only the design and construction flaws but also showed gaps in resilience in our built environment even while complying with updated code provisions.
Key issues identified included:
Design-related:
Insufficient stiffness to control deflection
Inadequate bracing of primary structural members
Lack of verified continuous load path
Construction-related:
Missing bolts
Poor welds
Oversized holes
Members installed out of plumb
Although these issues went unnoticed for years, they significantly contributed to the failures when buildings were subjected to the January 2026 snow and ice events. Failures were also observed in code-compliant building. In some cases, the lack of redundancy in the load path contributed to failure when loads exceeded code assumptions, specifically in buildings to older code standards. In others, aging, deterioration, and lack of maintenance are contributing factors.
Why It Matters
These recent storm events highlight a critical reality: code compliance alone is not a guarantee of performance under increasingly unpredictable climate conditions.
For building owners and operators—particularly in regions not historically exposed to prolonged snow and ice, these events underscore the importance of proactive evaluation. Aging structures, undocumented construction deficiencies, and evolving environmental loads all contribute to elevated risk.
As extreme weather patterns continue to shift, the industry must move beyond minimum code requirements and toward more resilient, performance-based design and maintenance strategies. Regular inspections, especially following atypical weather events, can help identify vulnerabilities before they lead to significant damage, operational disruption, or structural failure.
