How Much Snow Can Roofs Hold?

How Much Snow Can Roofs Hold?

Snow may be lightweight as individual snowflakes, however, it can exert a tremendous amount of pressure when it piles up on the roof. In today’s post, local roofing contractor Bone Dry Roofing answers the question: how much snow can roofs hold?

How Much Snow Can Roofs Hold

Factors That Affect a Roof’s Structural Strength

A structurally sound roof should be able to withstand the pressure exerted by piled-up snow. How much it can hold depends on many variables, the major ones being the following:

Snow density — Snow can vary in density, which is not readily visible from the ground. Dry and fluffy snow is significantly lighter than wet snow: a cubic foot of fresh powder can be as light as seven pounds, while a cubic foot of wet packed snow is usually closer to 20 pounds.

Roof pitch — The steeper the roofing pitch is, the more efficient it will be at shedding snow and rainwater. This means if your home has a low-pitched roof, it is more likely to accumulate snow on top. When planning a roof roof replacement, you have to consider that low-pitched roofs are less vulnerable to wind damage, which is a factor that should be balanced with its shedding capabilities.

Roof Material — Roofs with smooth surfaces can efficiently shed snow, and can offset a low roof pitch. This makes standing seam metal roofing the best candidate for this application. The material’s inherent durability is also a factor: laminate asphalt shingles and slate can support the weight of accumulated snow.

Preventing Dangers of Snow Accumulation

The pressure exerted by accumulated snow can cause damage to the roof. It may introduce cracks that may allow moisture infiltration as the snow thaws. Insufficient roof insulation can melt the snow on the roof and cause ice dams. In a worst-case scenario, a structurally-compromised roof may collapse.

There are ways to mitigate or prevent such dangers. One is to regularly remove the snow from the roof. You can choose from any removal method available—many of which can be used from the ground—but what’s important to remember here is you should not wait for snow to accumulate too much. Accumulated snow takes a lot longer and is more dangerous to remove. Investing in a properly built roof, with good insulation, can also help prevent snow from piling up in the first place.

Bone Dry Roofing is your leading provider of roof repair and installation services. Give us a call at (636) 489-1830. You can also fill out our contact form to schedule an appointment. We serve customers in St. Louis, MO, and surrounding communities.