Building Codes and Winter Snow Loads
One of the most important features of any modern structure is the fact that it doesn’t collapse under the weight of the world around it. This is never truer than in regions with heavy snowfall totals.
Most regions of the US will have specific standards and building codes surrounding snow loads and how much weight a metal building should be able to take. If you’re buying a steel structure, you’ll want to know that your design is up to snuff and capable of handling tough winters.
Below, we’ll explore snow loads, building codes, and why steel building owners need to have a keen understanding of how it all works.
Snow Loads 101
What is snow load? You’ll see this term used often, but the actual measurement is typically broken into two categories:
Ground Snow Loads
Ground snow loads describe the lateral forces that snow creates on the sides of your building. Large snow drifts can put immense pressure on your structure, leading to warping, damage, and structural failure.
Roof Snow Loads
As you can imagine, roof snow load is the amount of weight that your metal building roof can handle without failing.
In most areas, building officials will have set guidelines on snow loads. Buyers will need to prove that their building design is capable of withstanding the average snow loads before being approved for construction.
Building Codes and Who Enforces Them
Local building codes spell out exactly how much weight a roof must be able to handle, and those numbers aren’t arbitrary. They’re based on decades of climate data, engineering standards, and safety considerations. Before you break ground, it’s worth knowing how these rules are set, who enforces them, and why the details matter.
Understanding the codes:
In most places, snow load requirements come from a local version of the International Building Code (IBC). States adopt the IBC and may add their own adjustments. Alongside this, ASCE 7 lays out the methods for figuring snow loads, wind forces, and other environmental factors a building must handle.
Who decides what’s required?
The local building department is the group that reviews your design, signs off on permits, and inspects the work once it’s done. They’re the final word on whether your plans meet the area’s standards.
The role of engineered, stamped plans:
When a licensed engineer stamps a plan, it means the design has been calculated to withstand the specific snow load for your location. Without that stamp, the permit process can stall, and the structure might not be safe when heavy snow hits.
Why one location’s numbers don’t fit another’s:
Snow load values shift with factors like elevation, terrain, and even small changes in climate. A building site just a few miles away might have completely different requirements. The only safe approach is to verify with your local building department before you start.
Also Read - How Clear-Span Metal Buildings Handle Snow Loads and High Winds
How to Find Your Local Snow Load Requirements
To determine the snow load minimums in your region, you can do one of several things.
Call Local Building Authorities
Contact building inspectors in your county and ask about roof snow load requirements for your parcel.
Check Online
Visit city and county websites for permit guides and current building codes.
Get engineer-stamped drawings
Your engineered drawings will display the snow loads for the building design you’ve chosen, which you can use to compare to the county regulations where you live.
Use the Online ASCE7 Hazard Tool
You can use this online application to view local building regulations related to snow and wind loads.
How Snow Loads Change a Steel Building’s Design
If you’ve ever seen what a heavy winter can do to a roof, you know snow isn’t just decoration. Its weight, and sometimes a lot of it. That weight doesn't just sit on the panels; it pushes through the framing, the bracing, and right down into the foundation. How your building is put together will determine whether it shrugs off that load or struggles under it.
Roof Pitch
The steeper the roof, the harder it is for snow to stick around. Instead of piling up, it tends to slide off on its own. That simple change can mean your panels and framing carry far less weight throughout a winter.
Frames, Trusses & Purlins
Big snow years demand stronger support. You might be looking at heavier frames, closer purlin spacing, or upgraded trusses to keep things rigid. It’s all tied to the idea of clear-span strength—how far your structure can stretch without bending under pressure.
Bracing & Connections
Snow is rarely the only factor. Throw in a strong winter wind, and now you’ve got forces pushing from the side and down from above at the same time. Extra bracing and beefed-up connections keep the whole frame locked together so it doesn’t shift or twist.
Roof Panel Orientation & Gauge
Panel design isn’t just about looks. The profile, thickness, and fastening pattern all affect how well the roof handles both snow load and wind lift. Choosing the right combination means the panels stay put, even when conditions get rough.
Foundations & Anchor Systems
Buildings that will encounter more weight will require heavier anchor systems and thicker concrete foundations.
How Different Regions Influence Building Codes
Snow behaves differently depending on where you are, and building codes adapt to match those local conditions.
Mountain West & High Elevations
Up in the high country, winter can dump snow that’s both deep and long-lasting. Roofs often have to be designed for some of the heaviest loads around, and wind-driven drifts are a common challenge.
Upper Midwest & Snowbelt
In this part of the country, it’s not unusual for roofs to carry a steady, even blanket of snow for much of the season. Where buildings have multiple levels, the design also has to account for snow drifting and piling up against changes in height.
Northeast & Great Lakes
Snow here can be wetter and heavier than in other regions, which adds to the weight pressing down on a roof. Ice dams, caused when meltwater refreezes at the roof edge, are another issue that often factors into both design and upkeep.
Pacific Northwest
Snow isn’t constant in most parts of this region, but when it does show up, it’s often thick, wet, and heavy. One extra consideration is rain falling on top of existing snow, which can quickly add weight and stress to a structure.
Mid-Atlantic & Southern States
Snow is less frequent here, but the codes still require a minimum level of protection. That way, when the rare big storm rolls in, the roof is ready for it.
Permit and Compliance Checklist
Below, we’ve put together a quick checklist to guarantee that your project complies with local building codes:
Step 1: Confirm Code Edition
Check to identify the code year to be sure you are operating by the current codes.
Step 2: Get Official Snow Load Numbers
Determine the snow load requirements for your region.
Step 3: Order Engineer-Certified Plans
Most metal building providers will provide custom engineering drawings for your structure for an additional fee. These drawings will be required during the permitting process.
Step 4: Submit Permit Application
Complete the permitting process with your local building authority and include all required documentation.
Step 5: Pre-Install Review
Building inspectors will provide a preliminary approval that allows you to begin construction. During this process, you will be subject to several inspections at different stages of completion.
Step 6: Final Inspection
After completion, your local building inspector will carry out a final inspection to determine whether your structure is built to handle the weather and is safe to inhabit.
Winter Safety Tips to Avoid Heavy Snow Loads
You’re not powerless when it comes to protecting your prefabricated metal building from Jack Frost’s touch. We have several tips to keep your building looking and functioning its best this winter:
- Monitor for snow drifts after storms and windy days.
- Chipping at snow or ice can damage components and finishes.
- Check gutter systems and keep them clear to minimize ice damming.
- Inspect anchors, bracing, and seals after big snowstorms.
- Consider adding snow guards to avoid falling or sliding snow in doorways.
Common Mistakes with Snow Loads
During the winter, there are several pitfalls that can lead to costly issues with your metal building. These include:
- Using a neighbor’s snow load as a guide for your own
- Buying a non-certified metal building kit for an area with heavy snow accumulation
- Upgrading panels but not the framing and anchoring
- Skipping permits and inspections
Also Read - Why 24×30 Metal Garages are Perfect
Frequently Asked Questions About Snow Loads
With regulations varying by location, it makes sense that you have a few questions about snow loads in your area. To help, we’ve answered some frequently asked questions on the topic:
What’s the difference between ground and roof snow loads
Answer: Ground snow loads are a measure of the lateral forces on a structure from adjacent snow, while roof loads are a measure of snow’s weight on your building’s roof.
Do I need engineer-stamped plans for a steel building?
Answer: If you live in a region with heavy permitting regulations and high snow load requirements, you may want to purchase engineer-stamped plans to minimize hangups with the permitting process.
Can I overbuild beyond code for extra safety?
Answer: Yes. Depending on your budget and plans, you can add framing and paneling reinforcements, anchor bracing, and thicker concrete to over-prep your structure for its environment.
Will Roof Pitch solve snow loading problems?
Answer: While it can certainly help, additional features such as thicker framing and paneling can serve to better prepare your structure for handling the added weight.
How do inspectors verify that my building meets load requirements?
Answer: Building inspectors will use your engineer-stamped plans and on-site inspections to determine whether your structure meets local snow load minimums.
Snow Loads Matter
Taking the time to purchase a certified metal building and secure the proper permitting is a big part of preparing your structure for its environment. Knowing snow loads and performing the necessary due diligence can make all the difference in how well your structure performs and how smoothly the permitting process will go.
Direct Metal Structures is proud to offer a wide range of certified steel buildings for any region. Our designs are made from premium steel components and are built specifically to your local environment, so you can rest easy knowing your building is ready to take on any weather.
Get a Free Snow-Load Readiness Check >> Prefer to talk it through? Call us at 888-277-7950 - We’re happy to help you design it right the first time.