Every steel building quote should reference wind and snow load ratings, but if you're not in construction or engineering, the numbers themselves don't mean much on their own. Here's what they actually represent, why they're not optional, and how they affect what you're buying.
What Load Ratings Actually Measure
Wind load is expressed as a design wind speed (in miles per hour) that the building is engineered to withstand without structural failure. **Snow load** is expressed in pounds per square foot (psf) — the weight of accumulated snow the roof structure is engineered to carry before it's at risk. Both numbers are set by local building codes based on decades of regional weather data, not chosen arbitrarily by a manufacturer.
Why These Numbers Are Set Locally, Not Nationally
Wind and snow load requirements vary significantly by region, and often by county within the same state. A building engineered for coastal Florida's hurricane wind speeds is engineered very differently from one built for heavy lake-effect snow in the Great Lakes region, even though both might be the same size and shape. This is exactly why a generic, one-size-fits-all steel building spec doesn't hold up well across different parts of the country — the engineering has to match the location, not just the building size.
How Load Ratings Affect the Building Itself
Load requirements aren't just a number on a permit application — they directly shape the engineering of the structure:
- Steel gauge: higher load requirements typically call for thicker-gauge steel.
- Arch spacing and fastening: tighter spacing and additional fasteners add strength for higher wind and snow ratings.
- Foundation design: higher loads require a foundation engineered to transfer that additional force into the ground without shifting.
- Base connection type: heavier-duty base connections are often specified for high-wind regions to keep the structure anchored.
What Happens If a Building Isn't Rated for Its Location
A building engineered for a lower wind or snow load than its actual location requires isn't just a compliance problem — it's a real structural risk. Undersized snow load ratings are one of the most common causes of steel building roof failures in heavy-snow regions, and undersized wind ratings are a major factor in storm damage claims. This is also why building departments require engineered plans referencing local load requirements before issuing a permit in most areas.
How to Know What Your Project Needs
Your local building or zoning department can confirm the wind and snow load requirements for your specific address — this is public information tied to your jurisdiction's adopted building code. When you're comparing steel building quotes, it's worth asking directly whether the load rating quoted is generic or specific to your delivery location.
How Duro Span Handles This
Every Duro Span building is engineered to the wind and snow load requirements of the state and county it's being delivered to, not a generic national rating. That engineering is built into the gauge, arch spacing, and foundation recommendation from the start, so the building matches the code your local permitting authority is actually checking against.
Want to know what load rating your project needs?Call 888-848-2011 and we'll walk through your location's requirements, or
get a free quote to get the engineering started.