Barndominiums are a popular and stylish alternative to traditional homes, combining the durability of steel construction with custom residential interiors. However, while these structures are robust and versatile, they must be designed to withstand environmental forces—especially snow load in colder climates. Whether you’re building in Colorado, Montana, or upstate New York, snow load calculations are a non-negotiable part of safe and compliant barndominium construction.
In this article, we’ll take a deep dive into what snow load is, how it affects barndominiums, and how to calculate and engineer for it to ensure your structure remains safe, sound, and up to code.
Understanding Snow Load: The Basics
Snow load refers to the downward force on a building’s roof caused by the accumulation of snow and ice. Unlike wind load or seismic load, snow load is static, but that doesn’t make it any less dangerous. Roofs that are not adequately designed for snow load can collapse under the weight, causing property damage, injury, or worse.
There are generally two types of snow loads to be aware of:
- Ground Snow Load (Pg) – The weight of snow on the ground, typically measured in pounds per square foot (psf).
- Roof Snow Load (Pf) – The actual load transferred to the roof structure, which is usually a fraction of the ground snow load.
Snow loads vary significantly across the United States and are affected by:
- Elevation
- Latitude
- Roof pitch
- Exposure to wind
- Heat loss from the building
Why Snow Load Matters for Barndominiums
Barndominiums often use metal roofs and large spans without interior support, which can make them more susceptible to snow-induced structural stress. Moreover, if improperly designed, snow can drift or accumulate unevenly on the roof—especially around eaves, ridges, and valleys—creating concentrated loads.
Failing to consider snow load can lead to:
- Sagging or collapse of the roof
- Warping of wall supports
- Cracks in interior finishes
- Water intrusion from ice dams
Thus, calculating the correct snow load isn’t just about passing code—it’s about protecting your investment and your family.
Special Snow Load Considerations
- Drift Loads
Wind can blow snow off parts of the roof and deposit it in others. This creates drifted snow, which applies uneven loads. Engineers must assess:
- Ridge drift
- Eave drift
- Valley drift
- Parapet drift (if applicable)
- Sliding Snow
Snow sliding off metal roofs can be a hazard, especially for attached structures like porches. Snow guards can mitigate this.
- Ice Dams
Warm air leaking from the barndominium can melt snow, which then refreezes at the eaves, causing ice dams. These prevent proper drainage and increase roof load. Proper ventilation and insulation help avoid this.
How to Engineer Your Barndominium for Snow
- Choose the Right Roof Pitch
- Steeper roofs shed snow more efficiently.
- A pitch of 6:12 or greater is ideal in snowy regions.
- Use Proper Framing
- Opt for heavier-duty rafters or purlins.
- Space roof trusses closer together (e.g., 16″ OC instead of 24″).
- Upgrade the Roof System
- Use high-gauge steel roofing.
- Add extra bracing to rafters and trusses.
- Insulation and Ventilation
- Proper attic insulation prevents snow melt.
- Ridge and soffit vents promote airflow and reduce condensation.
- Consult a Structural Engineer
- Always have your snow load analysis reviewed and stamped by a licensed structural engineer.
- They’ll factor in local codes, live loads, and drift scenarios.
Code Compliance and Permitting
Local building departments may require:
- Site-specific snow load analysis
- Engineered drawings
- Structural calculations stamped by a professional engineer (PE)
Skipping these steps can void your building permit or insurance policy, especially if structural failure occurs later.
Conclusion: Snow Load Is Not Optional
Snow load calculations are essential for any barndominium being built in a cold or mountainous region. Ignoring this factor can lead to catastrophic structural failure, not to mention costly repairs and legal headaches. Fortunately, with proper planning, engineering, and construction practices, your barndominium can stand up to the harshest winter storms.
Whether you’re a DIY builder or hiring a contractor, make snow load part of your early planning. It’s not just about complying with code—it’s about ensuring your home is safe, resilient, and built to last for decades to come.