Before Canada’s icy winter begins, fall is a great time for homeowners to review what state their attic insulation is in. Insufficient attic insulation increases the possibility of ice dams forming on homeowners’ roofs. This phenomenon can lead to unwanted and costly leaks and roof shingle damage. Carry on reading this blog to learn everything you need to know about attic insulation and ice dams.
What is an ice dam?
An ice dam occurs when ice builds up on the eaves of sloped roofs belonging to a heated home. Heat loss from the home contributes to melted snow flowing down to the eave and freezing there. This creates a series of dangling icicles that hang towards the ground below.
When these dangling icicles are in place, it obstructs meltwater from being drained properly. The result is a backup of meltwater which often causes roof water leakage and associated damage to the internal structure of a home.
What causes ice dams?
Three factors work simultaneously to create an ice dam. Firstly, there’s heat loss from your home, secondly there’s the amount of snow cover, and thirdly, is the outdoor temperature. Ice dams will only form if your home has snow on its roof. Typically, your upper roof must be above 32°F / 0°C freezing, whereas lower surfaces are below 32°F / 0°C freezing.
Snow that has settled on your freezing upper roof will melt, trickling down to the colder below freezing section of your roof. This meltwater freezes, causing the ice dam. As more and more snow settles on your upper roof surface, the ice dam will expand but only along the colder below freezing section of your roof.
Once the ice dam has formed, any more snow/meltwater gets backed up behind the dam. Remaining in liquid form, this meltwater has nowhere to go except through tiny roof cracks and openings into your attic. It doesn’t end there because depending on the severity of roof leakage, water may percolate through ceilings and exterior walls too.
What damage is caused by ice dams when left uninspected?
Ice dams might look pretty but they should never be left uninspected. The damage caused by ice dams includes:
- Torn off gutters
- Loosening of roof shingles
- Roof and attic leakage
- Water leaks in home insulation
- Ceiling water leaks
- Exterior wall water leaks
- Warped flooring
- Peeling wall paint
- Stained and sagged ceilings
- Mold and mildew growth
What types of attic insulation are the most effective?
For an extra layer of protection this winter, homeowners should review what state their current attic insulation is in. If you’ve lived at your property for a long time and have never maintained or replaced deteriorated attic insulation, chances are you could be more prone to drafts experienced during cold bouts of weather.
Not only that but this poor energy efficiency could mean you’ve grown used to paying more to heat and cool your home. The best attic insulation helps homeowners to effectively maintain their desired indoor temperature year-round. In Canada, there’s typically four types of trusted attic insulation.
Blown in attic insulation
Blown in attic insulation is a popular choice since it’s eco-friendly and can be applied in wall cavities too. This type of attic insulation settles over an extended period, adapting to your own attic space. Blown in attic insulation is usually applied with either fibreglass or cellulose.
Spray foam attic insulation
An alternative to fibreglass, spray foam attic insulation takes up less space and prevents any humidity damage or heat loss. This type of insulation is used for homes with sloped roofs where joist cavity space is limited and where a higher R-value material is required.
Batt attic insulation
Naturally non-flammable, batt attic insulation is another popular choice, especially for homeowners who take their budgeting seriously. Made of fibreglass or mineral wool, batts are precut into industry-standard sizes designed to fit perfectly into attic crevices.
Attic air sealing
This isn’t insulation as such but still contributes towards indoor comfort and energy efficiency. By getting attic air sealing performed, you’re plugging any major air leaks to help maintain your desired temperature throughout your property. Many homeowners choose a combination of attic insulation and air sealing for the best possible protection, and ice dam avoidance.
What are insulation ratings and where should my attic rank?
Any home’s attic insulation is measured in R-values per inch of thickness. An R-value describes the insulating material’s resistance to heat flow. In other words, how effective insulation can stop heat from escaping or entering your home.
R-values differ depending on the type, thickness, and density of insulation materials. In general, Canadian attic insulation is recommended to be between R 50 and R 60 on the R-value scale. Nevertheless, Canadian winter temperatures plummet the further north-northeast you go. Therefore, for homes located in these regions, attic insulation with a greater R-value is likely required.
Don’t forget, AmeriSpec can provide Home Energy Evaluations and help you with Canada’s Greener Homes Grant program
Insufficient attic insulation and associated heat loss isn’t only a drain on your home but your finances too. A
Home Energy Evaluation from AmeriSpec can help. Whether you’re a homeowner, homebuyer, or a home builder, our Natural Resources Canada trained and licensed Home Energy Advisors can provide you with an EnerGuide Rating or ENERGY STAR® certification on your home and valuable information on how to make it more energy efficient.
Elsewhere, AmeriSpec can help you take advantage of Canada’s Greener Homes Grant program too. Our EnerGuide Energy Efficiency Evaluation will help guide you in making energy-efficient retrofits as part of the grant program. To kickstart the process, visit the
Greener Homes Grant portal, and select AmeriSpec of Canada as your service organization when you complete the application form.
More Than Inspected. AmeriSpec Inspected. 