Why Are Ice Dams Forming On My Roof
Posted in Attic Insulation, on January 27, 2022
There are a few reasons why you might have icicles on your roof. Icicles form when the temperature around your house is below freezing, the dew point is above that temperature, and you have moisture in the air like when the wind blows. The wind will cool the roof, and if it's not cold enough for frost, the moisture on the roof can freeze and form icicles. Icicles aren't just a sign of poor attic insulation in Toronto; they can also indicate cracks in your roof.
Icicles form on the eaves this time of year, often because of insufficient attic insulation. They are a sign of a heat loss path right through your roof to the outside world. High-quality insulation materials, such as spray foam insulation, can save you money and increase your comfort level throughout the year. If you have icicles forming on your eaves, it's worth taking a closer look at insulating your attic properly.
Icicles On Your Roof Can Be Caused By:
- Inadequate attic insulation
- Not enough insulation installed
- Insulation that has a poor insulation level
Evaluating Your Attic Insulation In Toronto
A proper attic insulation installation in Toronto begins with a heat loss analysis. This involves taking an infrared temperature reading of your ceiling and walls. We also measure for air leaks and moisture levels. The results provide us with a detailed plan to maximize your home's energy efficiency.
Insufficient attic insulation or poorly installed insulation
If the roof deck is cold and the air inside the attic is warm, water vapor will condense on the underside of the roof sheathing, where it can freeze. This is known as "icing" or "tenting." This happens because the warmer air under your attic floor has a higher moisture content than the cooler air outside and above your house. Suppose there is not enough spray foam insulation in your attic, and you live in a place that gets cold at night and/or during winter. In that case, you can experience ice dams, which are large accumulations of ice and snow on your roof (also known as "roof rime") that melt and flow down the roof shingles and drip onto your home. Icicles are simply small accumulations of ice that hang below roofs with lots of extra insulation.
How Ice Dams Form
Ice usually forms at the edges of a roof where wind-driven rain, snow, and other precipitation lands. It can also develop along roof edges where ventilation penetrations occur, and air can flow out of the building. When ice forms at exposed roof edges, it can drip or fall below. Because icicles form on the roof’s edge, they will only form when the roof edge is above freezing. When there is a lot of melting from snow and rain, frequent icicle formation is usually an indication that the insulation level on your roof isn’t as high as it should be. When this occurs, you should consult with a professional contractor (like one of our team members at Four Seasons Home Insulation) who can help you determine what insulation upgrades may be needed and the associated costs.
Why Is Ice Build Up Happening?
If a roof lacks sufficient insulation, the metal in the panels will be cold enough to freeze any water that comes in contact with it. As water freezes, it expands and breaks apart the metal substrate of the panels, creating large holes and allowing snow to accumulate in between them, which can increase the risk of leaks. We recommend that you hire a professional insulation contractor to inspect your home’s attic insulation – they may be able to identify issues you might not have even noticed, like gaps around pipes or missing insulation.
When a home insulation contractor arrives on-site and sees icicles forming around the attic or roof, it’s usually a sign that thermal bridging or air leakage is occurring in the building and that an upgrade to your home’s attic insulation is probably needed. Contact Four Seasons today to ensure the spray foam insulation in your Toronto attic is adequate.