Preliminary Research on Snow Load Damage

Title: PRELIMINARY Exhaustive Report on Snow Load Damage Evaluation and Repair Process

Prepared by Caleb Vorpahl of StructSolve Engineering

Purpose

The purpose of this report is to provide contractors with a detailed analysis and procedural guide regarding the evaluation, design, and permitting process for addressing snow load damage to residential roofs. This document consolidates StructSolve Engineering’s findings, methodologies, and best practices, ensuring clarity in the resolution of snow load damage claims. The goal is to provide a comprehensive framework for identifying the root causes of damage, assisting with insurance claims, and implementing design solutions in compliance with the International Residential Code (IRC), International Building Code (IBC), and local snow load requirements (International Code Council, "International Residential Code for One- and Two-Family Dwellings"; "International Building Code").

Scope

This report covers the evaluation process for identifying snow load damage on residential roofs, determining the predominant cause of damage (whether snow load or improper installation), StructSolve’s recommendations for insurance claim support and best practices for ensuring compliance with IRC, IBC, and municipal codes (Federal Emergency Management Agency).

Background

Snow load damage is a common issue in regions with significant snowfall. Residential roofs are designed to withstand specific snow loads based on geographic and climatic conditions, as outlined in building codes. However, when snow loads exceed these design parameters or when roofs are improperly installed, structural failures can occur (FEMA, "Snow Load Safety Guidance"). Insurance policies often cover snow load damage but exclude coverage for damage caused by improper installation. StructSolve Engineering’s role is to bridge the gap between technical evaluation, insurance support, and the design of repair solutions.

Findings

Identifying snow load damage involves understanding key indicators and applying systematic tools and techniques. Specific structural indicators of snow load damage include sagging rafters or rooflines, which often manifest as visible dips or deflections along the roof. Cracks in walls or ceilings, particularly near load-bearing components, are another clear sign of excessive stress (Simpson Gumpertz & Heger Inc.). Broken, split, or deformed rafters and trusses are often observed in attics or crawl spaces. Roof inspections frequently reveal uneven deflection, particularly in valleys or flat areas where snow tends to accumulate. Additionally, external signs such as ice dams and water pooling often indicate snow-related stresses on the roof structure. Water damage typically presents itself as leaks, stains, or visible moisture infiltration in ceilings and walls, often accompanied by compromised attic insulation (FEMA, "Risk Management Series: Snow Load Safety Guide").

To explicitly determine snow load damage, engineers employ several direct evaluation techniques. Thermal imaging cameras, while useful for detecting moisture or heat loss, do not directly determine snow load damage. Instead, engineers rely on physical assessments, including visual inspections and structural analysis. Direct techniques include measuring roof deflections under load, analyzing stress points in rafters, and correlating observed damage to known snow load events. These evaluations are supplemented with calculations referencing FEMA’s "Snow Load Safety Guidance" and ground snow load requirements from the IRC.

Other critical tools and methodologies include the use of moisture meters to confirm water infiltration linked to snow melting and re-freezing, which exacerbates structural stress. Engineers also analyze construction plans and material specifications to determine whether the structure was originally designed to withstand code-mandated snow loads. In cases where structural deficiencies exist, documentation of these failures is crucial to delineate snow load-related damages from pre-existing issues or installation errors.

Determining the predominant cause of damage requires a systematic evaluation process. Engineers must first confirm that the damage aligns with structural failure due to snow load. This involves cross-referencing local ground snow load requirements with actual snow conditions at the time of failure, as outlined in resources such as FEMA’s Snow Load Safety Guidance and the IRC Appendix D. Structural calculations are then performed to verify the original rafter design’s capacity against the prescribed load requirements. If evidence of improper installation—such as missing fasteners, undersized rafters, or inadequate connections—is discovered, this must also be documented. When the roof’s design meets or exceeds local snow load requirements but fails due to excessive snow accumulation, the cause is classified as snow load-related. Conversely, if improper installation is determined to have contributed to the failure, it is classified as installation-related, potentially limiting insurance coverage (International Code Council, "International Building Code").

To support insurance claims, StructSolve engineers prepare comprehensive snow load evaluation reports. These reports include detailed structural calculations, photographic evidence, and explicit references to relevant building codes such as the IRC and IBC. Additionally, snow load letters are drafted to articulate professional opinions on the cause of damage and substantiate the claim. By providing clear, technical documentation, engineers ensure that all stakeholders have the necessary information to process the claim effectively.

Best Practices

Maintaining detailed and organized documentation is essential for ensuring accuracy and professionalism throughout the evaluation, design, and repair processes. StructSolve engineers utilize standardized templates to ensure consistency in reporting and documentation. Communication with stakeholders, including homeowners, contractors, and insurers, is prioritized to maintain transparency and alignment. Adherence to the latest IRC, IBC, and local building codes guarantees that all designs meet current regulatory standards. Quality assurance measures, such as post-construction inspections and final certification reports, are integral to ensuring that repairs are executed correctly and effectively address the identified damage (International Code Council).

Conclusions

StructSolve Engineering’s exhaustive approach to snow load damage evaluation and repair provides a comprehensive framework for resolving complex structural issues. By identifying the root cause of damage, supporting insurance claims with professional documentation, and designing code-compliant repair solutions, StructSolve empowers contractors to restore structural integrity and build confidence among homeowners and insurers. This systematic process not only meets technical and regulatory standards but also fosters trust and collaboration among all stakeholders.

References

• Federal Emergency Management Agency. "Snow Load Safety Guidance." FEMA, 2014. https://www.fema.gov/sites/default/files/2020-07/fema_snow_load_2014.pdf.

• International Code Council. "International Residential Code for One- and Two-Family Dwellings." ICC, 2021. https://codes.iccsafe.org/content/IRC2021.

• International Code Council. "International Building Code." ICC, 2021. https://codes.iccsafe.org/content/IBC2021.

• Simpson Gumpertz & Heger Inc. "Evaluating Snow Loads on Structures." SGH, 2021. https://www.sgh.com/wp-content/uploads/2021/02/Topic-Brief-Evaluating-Snow-Loads-on-Structures.pdf.

• FEMA. "Risk Management Series: Snow Load Safety Guide." FEMA, 2021. https://www.fema.gov/sites/default/files/documents/fema957_snowload_guide.pdf.