Now that Toronto’s winter has officially started (or will be, depending on when you read this) with the first snowfall, it’s time to talk about the dreaded ice dams that destroy many roofs during this season.
Ice dams are formed by continual thawing and freezing of melting snow. Often, heat escaping from a home will cause this event to occur. When snow on the upper part of a roof melts, the water runs down the rest of the roof and freezes, forming thick ice sheets. Over time, the water runs down to the edge of the roof, where it refreezes creating a dam. As more and more water makes its way down the roof, it creates a pool. Gradually, the pooled water will make its way back up the roof, getting under the shingles and eventually causing leaks.
The main cause of ice dams is too much heat escaping through the rough due to insufficient attic insulation. Also, improper attic venting can be an issue as well as poorly placed gutters on a roof. A professional roofing contractor will be able to tell what the problem is on site.
On the other hand, the event may be naturally occurring, as a roof that is continually exposed to bright sunshine will certainly have melting snow. Finally, inclement weather can be a factor, with icy and stormy conditions one day and balmy days the next adding to the melting and ice accumulation on Toronto roofs.
Improving attic insulation so that the warm attic air does not reach the roof’s cold surface will reduce melting snow. In addition, having a roofing contractor assess one’s attic’s ventilation system will keep the attic space cooler, further reducing melting due to the temperature variance. Also, gutters and eaves troughs should be lower than the slope of the roof, ensuring that water, snow and ice are able to easily drain. Finally, installing an ice and water shield membrane in high-risk areas is a necessity on every Toronto roof. This is a second line of defense in case water gets under shingles, stopping any water or ice from penetrating the roof deck.
Since ice dams can be naturally occurring, and even the best ventilation and insulation may not be enough to prevent it from happening, on your next re-roof, make sure that you hire a roofing contractor that installs protective membranes all over your roof, as well as an ice and water membrane on the areas most vulnerable to ice dams. At Archer Roofing, we take pride in our work and always use preventative measures, like our insistence on quality shingles as well as a synthetic underlayment and ice and water shields on every roof we install. Contact the best roofing contractors in Toronto for a free inspection or to discuss your roofing needs.