Snow is heavier than you might expect, so you should know what to look for
Roof shape and materials affect how much snow a roof can hold.
Fresh and old snow have different weights.
It is best to hire a professional snow removal contractor.
Warning signs of too much snow include sagging, drooping, and leaking.
Inspect a roof before the first snowfall to avoid problems.
Never get up on your roof to remove snow or ice.
That first snowfall can be magical until you remember the havoc that all that white fluffy stuff can wreak on your home. Most residential roofs in good condition can hold quite a bit of snow—usually around 20 pounds per cubic foot of fresh snow—before it becomes a problem. This is just a general estimate, however, which may leave you wondering: How much snow can a roof hold? To understand exactly how much snow your roof can hold, you will need to consider different factors, including snow type and the shape of your roof.
Since large amounts of snow on a roof can lead to dangerous and costly problems, including roof collapse, it is worth using this guide to learn everything you need to know about how much snow your roof can hold. Familiarize yourself with warning signs to look out for, as well as tips for removing snow if your roof becomes overloaded.
While 20 pounds per cubic foot of snow is a good general rule, several factors influence just how much snow your roof can safely hold before becoming overloaded.
Steep-pitched, angular roofs are better at shedding snow than flat roofs, thanks to gravity's natural force. So, if you have a flat roof, you will probably want to pay closer attention to snow pile-ups than folks with a steep-pitched roof.
A roof slope of around 30 to 45 degrees (a 6:12 to 12:12 pitch) is considered an ideal angle for optimal snow runoff. At this angle, the snow can slide off more easily, reducing the risk of excessive accumulation that could stress the roof structure. However, roofs with slopes steeper than 60 degrees (greater than 20:12 pitch) can pose safety risks in snowy conditions because of how quickly the snow may slide onto the ground below.
Regular maintenance and snow removal are crucial for flat or low-pitched roofs. These roofs are more prone to snow accumulation, which can lead to ice dams or even structural damage if the snow load becomes too heavy. In these cases, installing snow guards or heat cables can help manage snow buildup and prevent damage. The average cost to install snow guards is $1,500.
Ultimately, the best roof slope for snow depends on your climate and the specific design of your home. Consulting with a reputable roofing company near you can provide guidance tailored to your needs.
The material of your roof plays a significant role in how much snow it can hold and how it handles snow accumulation. Let’s take a look at how some popular roof materials hold up against snowfall.
Metal roofs: Metal roofs are particularly well-suited for snow-prone areas. Their smooth surface allows snow and ice to slide off more easily, reducing the risk of heavy snow buildup that can lead to structural stress. Metal roofs are also highly durable and less prone to damage from freeze-thaw cycles compared to other materials like asphalt shingles.
Asphalt shingles: This popular type of shingle can hold snow more readily because of its textured surface. This increases the chances of snow accumulating, which can put excess weight on the roof and potentially cause damage over time. They also may wear down faster under harsh winter conditions.
Wood or clay tile roofs: Although aesthetically pleasing, wood or clay tile roofs are heavier and less effective at shedding snow. Heavy snow on these types of roofs can increase the risk of leaks or structural strain. Proper maintenance and roof slope are critical to ensuring these roofs hold up under heavy snow conditions.
Different types of snow carry different weights per cubic foot. For example, a cubic foot of light, powdery snow will not weigh nearly as much as a cubic foot of very wet, packed snow.
You have probably noticed that snow can feel different at various times, whether you are trying to build a snowman or clear your driveway with a shovel. To truly understand the weight of snow on your roof, you will need to see what type of snow it is. You can check the snow on the ground to know what is on your roof.
It generally takes four feet of accumulation for fresh snow to weigh about 20 pounds per cubic foot.
Old packed snow weighs about twice as much as fresh snow. Generally, two feet of packed snow amounts to about 20 pounds per cubic foot.
Ice is much heavier than snow, so it only takes about one inch of ice accumulation to weigh around 20 pounds per cubic foot.
Although snowfall levels are unpredictable, you can prepare for the colder months by knowing the average snowfall in your area. This will help you plan ahead for scheduling roof snow removal services.
| Region | Average Snowfall (Inches) |
|---|---|
| West | 34.58 |
| Southwest | 8.7 |
| Midwest | 31.84 |
| Southeast | 7.87 |
| Northeast | 53.4 |
If you experience a big snowfall or ice storm and are wondering whether your roof is overloaded, here are a few warning signs.
When your roof is overloaded with snow, it might start to droop or sag. You can sometimes see this from the outside or from the inside of your home on the ceiling or rafters.
Inspect your walls for any new cracks, especially around interior door frames. If you notice new cracks or you have trouble shutting doors that normally close with ease, then snow on the roof might be causing structural issues and potentially dangerous problems with your house's framing.
Any new leaks in the home after a big snowfall are an indication that your roof is overloaded with snow and could be at risk of collapsing. For that reason, it is a good idea to spend some time inspecting your home's ceiling after major snowfalls.
It is normal for houses, especially older homes, to make creaking or popping noises from time to time. However, if you notice an influx of noises during or after a snowfall, it could be a sign that your house is under stress from too much snow.
The formation of ice dams points to excessive snow accumulation, as snow has to melt and refreeze to create an ice dam. If your area gets snowfall over a long period of time—especially if it is mixed with sleet or ice—consider getting it professionally removed to help prevent ice dams. This investment may help you to avoid ice dam removal costs, which average $1,200.
Your roof is not a safe place, especially during snowy or icy weather, so never attempt to go up there to remove snow. It is safest to hire a local snow removal professional or roofer near you to do the job for you. A local roof cleaner may even be able to help.
But while you’re waiting for a pro to arrive, use these tips to limit snow and ice accumulation on your roof.
If you have a one-story house, then you can purchase a telescopic snow roof rake, which lets you pull snow off the roof from the safety of the ground. You can purchase one from most hardware stores for $15 to $30.
A roof is colder at the eaves and overhangs, but the center of your roof is warm. That warmth melts the snow and ice, causing it to slide to your roof’s edge and freeze; this creates ice dams that prevent the roof from shedding snow. Sometimes all you need to do is use a shovel to get rid of the icicles and snow on the edge of your roof, at which point your roof might start shedding the snow on its own. Use caution here, too, though, as icicles and falling snow can be dangerous.
Attempting to remove all of the snow from your roof can potentially damage the shingles, since you will be shoveling very close to them. Instead, aim to remove half of the snow’s height and use a plastic shovel rather than a metal one to protect your roof from further damage. If you have an ice dam, you should hire a professional who can properly remove the entire blockage.
If you get hit with a heavy snowstorm, head up to your attic to ensure no snow has entered. Sometimes, snow from your roof can get sucked in by the roof's ventilation. A dusting of snow inside your attic is normal, but if you find drifts of snow, it could collapse the drywall ceilings below when it melts.
At this stage, there isn’t much more you can do as a homeowner without professional intervention. Hiring a pro is necessary to get this type of risky job done properly. You should anticipate paying an average of $300, or anywhere in the $200 to $700 range, for roof snow removal costs.
