How Roofs Stand Up to a Heavy Snow Load: Some Fun Facts
You may have cast an eye up at the winter drifts on your roof and thought to yourself, how much can it really take before you have an issue? Or what is it doing when all those flakes are piling on?
For 20 years now Heyn Brothers Roofing has been putting in the work to see that homeowners from Southeast Minnesota to Sioux Falls and Waterloo and beyond have roofs that will not be cowed by a hard winter. We would be happy to put some of the more interesting facts about snow load to rest for you, but if you want to talk about it with us, our Rochester number is (507) 519-6202.
More Weight to Snow Than One Would Suppose
It is something of a revelation to most: there is no such thing as uniform weight in snow. Fluffy, new-fallen snow is light, yet you make of wet, packed snow whatever you like. Moisture content alone can make the weight of a cubic foot of snow quite a bit different.
Just look at the disparity:
- A cubic foot of fresh dry snow is in the neighborhood of 3 pounds
- Packed snow runs about 12 pounds to the cubic foot
- You can be looking at 15 or 20 pounds for a cubic foot of heavy, wet snow
- Ice is close to 57 pounds per cubic foot
- An average roof with a foot of wet snow on it is carrying tons
So the next time someone speaks of a roof giving way under snow, chances are it was the density of it, not the depth, that caused the trouble.
A Load a Roof Can Be Made to Bear
These days a roof is put together with snow in mind. In northern climes such as Minnesota, Iowa and South Dakota the building codes are there for a reason; they dictate what a roof must be able to handle according to the local climate. The engineers have studied the weather patterns of decades past so the structure can endure what the winter puts in front of it.
Then there is the matter of shape. Gravity will do its job and slide the heaviest snow off a steep, sloped roof long before it gets to be hazardous. A flat or low-pitch roof does not shed snow with the same ease, which accounts for the prevalence of steeper roofs where it is snowy.
Ice Dams: A Threat That Creeps Up on You
Not every homeowner is aware that the snow is not always the problem, but what follows when it thaws and then refreezes.
Attic heat can warm the roof and get at the lower layer of snow. The water makes its way to the cold edge of the roof and turns to ice, an ice dam. Before long you have water backing up under shingles and into the house.
Some telltale signs of this kind of trouble are:
- Any thick ice ridges at the edge of the roof
- Gutters weighed down with icicles
- Stains on a wall or ceiling inside
- Dampness in the attic
- Paint that is peeling near the roofline
Proper insulation and ventilation in the attic will go a long way to ward off ice dams. If the roof surface is kept cold by a well balanced attic, the whole melt and refreeze process is nipped in the bud.
Designing a Roof to Put Up with Snow
The materials are part of the equation. With quality shingles, good underlayment and flashing in place, water is kept out even if the snow lingers for weeks. Being a CertainTeed Select ShingleMaster certified contractor we put in roofing systems made to withstand a northerly winter.
An old roof, or one with damage you cannot see, will not always do its duty. What might be a small leak or an absent shingle is no small matter once the ice and snow come down. A roof inspection by a professional before the season starts is wise.
Put Your Roof in a Better Position for Winter
Snow has its beauty but it is a lot of weight and a roof has to be prepared for it. Should you have concerns over storm damage or ice dams, or simply want to know the state of your roof, the people at Heyn Brothers Roofing are at your service. Our 4.8 star rating from 300 reviews and BBB A+ accreditation speak for themselves, as does the 5-year workmanship warranty we put behind our work in addition to the manufacturer’s.
We have 24/7 phone service and financing via GreenSky so you do not have to wait when the weather turns. For a free estimate call us in Rochester at (507) 519-6202, in Waterloo (319) 984-1680 or in Sioux Falls (605) 857-4770 and we will have your roof in order for the season.