Can Snow Be Too Heavy on a Roof?

Winter brings snow, and while it may look pretty, it can cause significant problems for commercial roofs. In this article, we will discuss the effects of heavy snow on commercial roofs and provide solutions to prevent or address potential damage.

How Much Does Snow Weigh on a Commercial Roof?

The weight of snow on a commercial roof varies depending on factors such as the type of roof, its size, the pitch, and the amount of snow. It also depends on the water content of the snow.

Generally speaking, 1 foot of fresh snow weighs between 3 and 7 pounds per square foot. This means that a 10-foot by 20-foot section of roof can be weighed down by 6,000 lbs or more under the right conditions.

As snow accumulates over time, it compacts and can create an excessive load. Compacted snow can weigh as much as 12 pounds per square foot. This means that the same 10-foot by 20-foot section of roof can be weighed down by as much as 24,000 pounds or more!

It’s easy to imagine what happens if your roof already has 12 inches of compacted snow and then another 8-12″ falls.

How much snow can an average roof handle?

On average, commercial roofs can handle between 20 and 40 pounds of snow per square foot before the roof is in danger of collapsing. This range can vary depending on the type of roof, its age, and the pitch.

Regardless, it is best to play it safe and remove any amount of snow that accumulates on a commercial roof. If there is significant accumulation (over 12 inches), consult a commercial roofing professional for assistance.

Effects of Heavy Snow on Commercial Roofs

It goes without saying that this weight can cause considerable strain on the roof, especially on flat or low-pitch roofs. But we’ll say it anyway because this is the most important takeaway of this article.

Commercial roofs are designed to withstand all sorts of extreme weather conditions, but heavy snow can still cause damage.

Here are some of the effects of heavy snow on commercial roofs:

  • Weight – Heavy snow accumulation can put excessive weight on the roof, which may exceed its load capacity. This weight can cause the roof to bow or collapse, leading to expensive repairs or even injuries.
  • Ice Dams – When the snow on the roof melts and refreezes, it can create ice dams. Ice dams can prevent water from draining properly, leading to leaks and water damage.
  • Roof Leaks – Heavy snow can also cause leaks on commercial roofs, especially if the roof is old or damaged. The weight of the snow can exacerbate existing issues or create new ones, such as cracks, holes, or gaps.
  • HVAC Malfunctions – Commercial buildings often have HVAC units installed on the roof. When snow accumulates around the units, it can block airflow and cause malfunctions. This can lead to reduced indoor air quality, higher energy bills, and potential health hazards.

Solutions to Heavy Snow on Commercial Roofs

Prevention is critical to avoiding the impact of heavy snow on commercial roofs. Here are some solutions that can help:

  1. Snow Removal – Removing snow from the roof can reduce weight and prevent ice dams. However, hiring a professional snow removal company that uses proper equipment and techniques to avoid damage to the roof or injury to workers is essential.
  2. Roof Inspection and Maintenance – Regular roof inspections and maintenance can identify and address potential issues before they become severe. A qualified roofing contractor can inspect the roof for cracks, leaks, or other damage and perform necessary repairs or replacements before the winter months.
  3. Heat Trace Systems – Installing heat trace systems on the roof can prevent ice dams by melting the snow before it refreezes. This system can be effective but requires professional installation and regular maintenance.
  4. Insulation – Proper insulation can reduce the heat lost through the roof, which can help prevent ice dams and roof leaks. Additionally, it can lower energy bills and improve indoor comfort.

Conclusion

Heavy snow on commercial roofs can cause various problems, from weight overload to HVAC malfunctions. However, commercial property owners can avoid or address these issues with proper prevention and maintenance.

Waiting until we get 12″ of new snow on top of 12″ of compacted snow can create a very dangerous situation. It’s best to schedule snow removal throughout the winter, particularly after heavy snowfall.

By hiring a professional commercial roofing contractor and performing regular maintenance, you can keep your roof safe and sound during winter.

Mint Roofing is your commercial roofing partner to keep your roof in Tip-Top condition all year round. Give us a call today!

Phone:  952-473-8080  24-Hour Line: 952-473-8181  Email: info@mintroofing.com or by sending a message HERE.

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