Snow will always accumulate, be it on a car or your home’s roof. If you recently had a roof replacement and it’s your first winter with it, then you’ll likely be a bit concerned on how much snow will accumulate throughout the season. If record snowfall is predicted in your area, you might start to worry whether it can hold all that weight.

If you’re wondering how much snow your roof can hold, our expert roofers at Pro Quality Construction Inc. share their insight:
Estimating the Weight on Your Roof
The exact amount of weight a roof can hold is often based on several factors, but most can typically support 20 pounds per square inch of weight before becoming stressed. Some roofs are even designed to support greater loads in areas and mountainous regions where snow tends to fall heavily at times!
To determine the weight of the snow on your roof, just keep in mind that around 10-12 inches of new snow is equal to one inch of water or about five pounds per square inch. A typically well-built roof could support 40-48 inches of new snow before it becomes stressed.
If the snow is packed, three to five inches of snow is approximately five pounds per square inch. Around 20 inches of snow would be the maximum amount of snow that your roof could handle. As for ice accumulated on your roof, one inch equals one foot of fresh snow.
Signs That Your Roof Can’t Handle the Weight
How much snow a roof can hold depends on certain variables such as type of snow, roofline and roofing material, among other considerations. It isn’t easy to know for sure if your roof can handle the weight unless you have it checked by a roofing and siding contractor. You’ll also need to consider the following to determine whether your roof is becoming stressed:
- Structural Design – Steep and smooth roofs shed snow more easily than flat or only slightly pitched roofs. In fact, melting snow tends to run off steeply sloped roofs that are greater than three inches of slope in 12 inches of horizontal distance, while ice and snow will accumulate more quickly on roofs that are either flat or have a low slope.
- Weight Of the Snow – Wet snow can be nearly three times heavier than dry and fluffy snow. A cubic foot of fresh powder might weigh in at seven pounds while that same amount of wet, packed snow could be closer to 20 pounds.
- Type of Roofing Material – When it comes to roof repair and replacement, go for the recommended materials such as asphalt or slate shingles. Both do well to support the weight of snow, asphalt shingles are more affordable and easier to replace.
Because of the different factors that affect each roofing system, what can be just a normal amount of snow accumulated on one roof can actually pose a higher risk on the roof of a neighboring home. This is why it’s recommended that you have yours checked by a trusted professional to ascertain more detail on the condition of your roof and be on the safe side.
Aside from looking at your roof from the curb, you’ll find more telltale signs indoors as well. Check your attic to see if you can find any hint to an impending problem. For instance, sprinkler lines, sagging ceiling tiles, popping or creaking noises, cracked walls, jammed doors and windows, or leaks are all signs of an overstressed roof.
You can also examine the rafters for any noticeable bends or cracks. Damaged rafters can be caused by snow, but there are other possible explanations as well such as termites. In any case, you’ll need a licensed roof repair contractor at this point to evaluate and address the problem properly.
Removing the Excess Snow
Removing the snow off your roof is optional, but if you’re planning on doing it yourself, it should be done with caution. If too much snow has accumulated, one wrong move might cause a “roofalanche”, which is a potential hazard with heavy snow loads on a roof. They’re similar to avalanches in a way that they’re large masses of snow that get dislodged when rain falls on the load. Once the snow is displaced, it can bury anything nearby and trap people who may be in its path. If this is the case, have it cleared by a trusted professional instead.
Preventing a Roof Collapse
You’ll need to clear the snow off your roof to prevent it from collapsing into your home. But doing this without taking precautions can be risky, especially if there’s a lot of snow accumulated on your roof. As we mentioned earlier, we recommend that you call in professional roofers to do this for you, but you can start by clearing the excess snow and ice. A snow rake with a long extension arm is recommended, and you can start doing this yourself to alleviate some of the weight off your roof.
Before you start raking away however, pay attention to where the snow pulled off the roof is likely to wind up. Be sure to pick a landing spot that won’t affect you or any unsuspecting bystander. Also don’t try to remove all the snow, as it could damage the roofing material and leave the roof vulnerable to leaks. Some roof rakes are fitted with rollers that keep the edge of the rake safely away from the shingles, so use those instead.
If the snow is too steep, don’t risk it and hire a professional contractor to finish the job. And if your roof is already damaged and looks like it’s in danger of collapse, don’t risk staying inside and vacate the premises immediately. You’re better off hiring a structural engineer to assess the problem.
You can count on our roofing and siding services at Pro Quality Construction Inc. to get the job done! Call us at (844) 499-7878 for more information. You can also fill out our online contact form, so talk to us today!