Ice Damming Can Be Problematic - the Key is to Prevent Ice Dams

Ice damming is a seasonal problem affecting many Canadian homes (and buildings) every winter. When ice damming is out of control, a number of problems can occur - so it’s vital to prevent ice dams. Ice damming can cause water to leak into the home. It can compromise the lifespan of roof materials. And it can often present a physical danger when big icicles fall down from the eaves.

The Source and Cause Of Ice Damming

Ice damming is a direct result of “differential” melting and freezing. When snow accumulates on the roof, it tends to melt in the upper areas where the temperature is warmer. The melting snow flows down to the lower areas of the roof, and begins to refreeze due to the colder temperature.

The melting/freezing dynamic is cumulative – in other words, more and more ice builds up and the ice damming takes on greater proportion. The only solution is to prevent ice dams entirely.  Even with various short-term solutions, the source and cause of the ice dams must be addressed. While a building owner might implement a specific snow management solution, this is not a long-term remedy. The optimum solution is to prevent ice dams by changing the physical conditions of the attic and roof cavity. Essentially, higher-than-optimal attic temperatures must be reduced.

To Prevent Ice Dams, It’s Imperative To Address The Origins

To prevent ice dams, its necessary to prevent roof snow from melting. This is accomplished by stopping heat transfer through the attic floor and roof cavity. When attic insulation is poorly installed or simply inadequate, it requires upgrading or replacement. And when air leakage is prevalent, the pathways through the ceiling, attic, and roof must be sealed effectively. These principles are the same for a residential home, a low-rise condo, or a commercial building. One of the biggest problems in addressing air leakage is creating a “perfect” air seal. Whether in the attic roof or the roof cavity, effective air sealing is problematic because of the complexity of shapes and contours throughout the space. In short, conventional insulating and sealing methods are not reliably effective. As such, efforts to prevent ice dams often come up short. Of course, the true proof of success is the complete absence of ice dams, the objective of any professional.

By any measure, air sealing is the key to reducing air movement and heat loss in the attic and through the roof. While insulation contractors know that every home and building is different mechanically, there are still commonalities when it comes to air sealing. The bottom line is that a combination of air barrier and thermal insulation will effectively prevent ice dams from forming. Few other combination approaches have proven to be as productive with long-term results.

Great Northern Insulation Addresses Ice-Damming Head On

With Great Northern Insulation, sealing the attic and roof cavity is the key to preventing ice dams. The idea is to create a complete “system” where attic and roof are properly sealed, insulated, and ventilated. It’s a system that effectively manages airflow, heating
and cooling, and air moisture. In addressing the issues of ice damming, GNI recommends a spray foam application for the very best results. Spray foam creates a thick, impermeable envelope that both seals and insulates the space at one time. No other product (or combination of products) delivers comparable results. The beauty of spray foam is that the entire attic space is completely sealed and insulated – this includes every gap and opening; all beams, plumbing, and wiring; and all ductwork.  The finished space is airtight, moisture proof, and insulated with higher R-Values than comparable products. For GNI, spray foam has become the insulation of choice for the attic. It’s a super efficient air barrier and serves as an effective moisture barrier at the same time. Air movement and air moisture are reduced, and therefore the dynamics of ice damming are prevented – there are no more ice dams.

The Benefits And Advantages Of The Spray Foam Installation

Throughout the home energy sector, spray foam is considered the ultimate product. But it’s also a premium installation, and may not suit every project budget. As such, the team at GNI recommends a “hybrid” installation to address issues in the attic and roof. The “hybrid” installation comprises two products that work together. As a first step, spray foam is installed throughout the attic and roof cavity in order to seal effectively, and further insulate the space. This is followed by an application of loose-fill insulation, which enhances the R-Value. The “hybrid” installation goes far beyond addressing ice dams. This approach provides a space that is airtight and moisture proof. Energy efficiency in the home is dramatically improved, and heating/cooling is much better balanced. Better still, seasonal energy costs are much reduced. With Great Northern Insulation on the job, the work is only complete when 
attic ventilation is also optimized. As part of the so-called “system”, proper attic ventilation will serve to prevent ice dams - efficient ventilation stops condensation from forming, and ensures good air circulation.

• Learn more about keeping your house warm this winter & energy efficient