Your cart is currently empty!
Understanding Roof Snow Load: What You Need to Know
Snow may look light and fluffy—but it can add a massive load to your roof. Here’s a quick guide to understanding how much snow and ice your roof may be supporting, and why it matters.
How Much Does Snow Weigh?
- On average, snow weighs about 20 pounds per cubic foot, or 1.25 pounds per square foot per inch of depth.
- Heavier, wetter snow can weigh up to 21 pounds per cubic foot, while light, dry snow may weigh as little as 1 pound per cubic foot.
Example:
If you have 20 inches of snow on your roof:20 inches x 1.25 lbs = 25 lbs per square foot of snow load
What About Ice?
Ice is significantly denser than snow. Add approximately 5.2 pounds per square foot for each inch of ice on your roof.
Important Considerations
- Building Code Standards:
Modern structures built with a permit are typically designed to handle up to 120 lbs/sq ft of snow load.
However, older buildings may not meet this minimum. - Manufactured Homes:
Until recently, many were only designed for 30 lbs/sq ft.
To verify your roof’s capacity, check the metal data plate (usually found in a utility closet or kitchen cabinet). - Low-Pitched Roofs (Under 3/12 Pitch):
These roofs are more prone to moisture retention and are at higher risk of structural stress. - Rain on Snow:
Excessive rainfall on existing snow can quickly increase the weight on your roof and dramatically exceed safe limits.
Should You Shovel Your Roof?
Proceed with extreme caution. While it may be necessary in heavy snow conditions, shoveling your roof can cause serious damage to shingles, membrane layers, and even structural components. Consider contacting a professional, especially for steep or high roofs.
Zaleski Snow Guards are designed to help manage snow loads safely, preventing dangerous slides and helping distribute snow more evenly. Combined with our recommended Surebond SB-190 adhesive, they offer a non-invasive, reliable solution for long-term snow load control.
Questions? We’re here to help you protect your home or building.