Understanding Snow Load & Ice Dams
Understanding Snow Load & Ice Dams
With winter in full swing and the Jackson Hole area being the lucky recipient of a healthy snowfall this season, we often receive questions from clients regarding their roof and the accumulating snow. You may find yourself asking the same questions - how much snow load can a roof handle? And how can you keep snow off of your roof?
How Much Snow Load Can a Roof Handle?
How much weight can a roof handle? The maximum snow load of your roof depends on several factors, many of which pertain to how and when the house was constructed. Ground snow loads (essentially how much snow lands on the ground) vary across the valley, from 75 psf (pound per square foot) to 175 psf. When designing a home, architects and engineers use these values to determine how robust the roof structure should be to resist these snow loads. Older homes – and those not designed by architects or engineers – may not necessarily be designed around these guidelines, and therefore, extra caution should be used when estimating the roof’s ability to hold snow.
Is It OK to Have Snow on Your Roof?
As previously mentioned, most roofs in our region are designed to withstand a modest accumulation of snow, but too much snow can become problematic over time. Though the snow that falls here is typically of low moisture content, we do occasionally see wetter storms pass through, which deposit densely packed snow on our structures. Also, as snow melts – sometimes due to temperature fluctuation and sometimes due to heat loss from your home – that water tries to find its way into your home. The other potentiality is that the water refreezes back into ice, creating ice dams, a sagging roof, leaks, or even causing the roof to collapse.
Should You Knock Down Icicles Off Your Roof?
You may think that knocking down icicles is a smart move for maintaining your roof—but in reality, removing icicles can break or damage gutters, downspouts, or other elements of the roof. If you have large icicles on your roof, it’s better to call in a professional to help with removal.
How Do You Keep Snow Off Your Roof?
Though it may seem counterintuitive, one of the best ways to keep snow off of your roof is by keeping your roof cold. This stops snow and ice from sticking, melting, and refreezing on your rooftop.
We as designers strive to lower the temperature of your roof; sometimes by improving ventilation, sometimes by increasing the insulation value, and sometimes both. You can also keep snow off the roof by simply raking it with a snow rake.
Other factors to consider?
A steeper incline will allow the snow to fall more easily off of the roof, especially with slippery roofing materials like metal. Shingles (asphalt or cedar) and other more abrasive roofing materials can hold snow longer. Obviously, the lower the slope of the roof, the more it’s going to retain snow.
How to Melt Snow on a Roof
Wondering how to melt snow on a roof? Here are some foolproof methods:
· Install heat cables on the edge of the roof
· Fill a long roof snow sock with ice and leave at the edge of the roof
· Apply chemical deicer to the roof
· Pour hot water on the roof
· Cool your attic down
· Use a rake
· Install snow guards
· Call a professional roofer
Ice Dam Prevention Tips
Ice dams are formed when ice builds up over time, causing a block that prevents snow from falling off of the roof. Fortunately, there are ways to prevent ice dams from forming in the first place. Here are some tips for prevention and removal:
· Rake your roof regularly
· Install heat cables
· Use a chip and hammer
· Pour warm water over the dam
· Get better attic insulation and ventilation
· Use an ice dam sock
Ultimately, much can be done initially in the designing of your home to help prevent ice damming and extensive snow load on a roof. A43 Architecture will help you design a home that not only suits your needs, but is suited for the sometimes extreme conditions that make Jackson, Wyoming so beautiful. Have questions? Call us today at: 307-249-8650.
Article source: Maximum Snow Load On a Roof [Your Ultimate Guide] by Roof Maxx