Which House Looks Like Yours in the Winter?
Garret and Erin, the owners of the home on the right, worked with B|E Retrofit to prevent ice dams and save energy in 2010. The solution at Garrett and Erin’s house works because its design is based on building science and it was installed with high-quality workmanship and attention to detail.
You have landed on this page to study ice dams. We will first describe what causes an ice dam, second we will debunk some common New England ice dam “solutions,” and then discuss proven strategies that can be used as guidelines to solve ice dam problems for every style of roof and attic design.
What Causes an Ice Dam?
Ice dams are a result of excessive heat loss out of a building. It is that simple. On a day when it is below freezing and heat reaches the underside of the roof surface, snow will melt.
What is the source of heat to melt snow on a day when it is 20°F outside? The answer: the 60°F - 70°F temperature in the living space of the house that is directly below the roof.
When heat from the house reaches the underside of the roof deck and melts snow, the water flows down the roof towards the eaves by gravity and then at the eaves (outside of the heat source of the living spaces below), the water refreezes. As this process continues throughout the winter, your ice dam grows.
The only way to stop this process is to block the heat leaving the living space from reaching the underside of the roof deck and melting the snow on the roof. If snow melts on a day when it is below freezing, it will refreeze at the eave.
Traditional “Solutions” Treat Only Ice Dam Symptoms
The common “solutions” that homeowners are most familiar with only treat the symptoms of ice dams, not the cause:
Many contractors also recommend “solutions” that don’t get at the root cause of the problem:
Unfortunately, homeowners will continue to chase ice dam problems and roof leaks every winter after choosing any of the options above. Roof rakes and roof shoveling will continue to be important parts of the winter chores if a homeowner selects one of the options above.
The only approach that can stop ice damming is to prevent the first step in the cycle: stop the heat from the house from reaching the roof surface.
Every Home Can Be Fixed
The approach to solve ice dams is straightforward: identify the pathways and sources that feed heat to the roof deck and then block 100% of them. This approach will take different forms, but it can be designed and implemented to fit every style of home construction.
The three most common ways that heat reaches the roof deck are:
Every Home is Different
The location of the air leakage control and insulation systems is dependent on the construction of the home. B|E Retrofit understands that every building is different, so we custom design solutions for each individual home. Barriers can be built at a flat ceiling surface or directly in contact with the underside of the roof surface.
As noted above, the principles of ice dam control are simple, but designing projects in existing buildings is challenging. This is why understanding the science behind each project is critical. B|E Retrofit has studied and worked with North America’s leading building scientists and engineers to design and install solutions for our clients. Our expertise and relationships ensure that every project is a success.
Working with B|E Retrofit
B|E Retrofit is known for executing smarter and deeper home energy retrofits than our competitors. A smart retrofit is designed using building science principles, consistent with the complex flow of heat, air and moisture in a home.
Understanding these forces leads to a retrofit that improves the health, comfort, durability and energy efficiency of your home. A deep energy retrofit is a project that pursues aggressive levels of total energy savings. An ice dam prevention project can be an excellent way for a homeowner to consider the benefits of a deep energy retrofit that can lead to 50% - 90% total energy savings.
Join our growing list of clients that have eliminated ice dams once and for all. We are proud of the work that we do and the relationships that we create with our clients. We are happy to connect any interested homeowners with our network of satisfied clients.
A White Paper on Ice Dams from B|E Retrofit
Retire the Roof Rake:
With careful planning and custom design and execution you can be sitting inside a warm house in the winter and not raking or shoveling your roof. Every style of roof can be retrofitted to prevent frustrating ice dams, water leaks and interior damage.
Ice dam prevention strategies differ widely for different roof and attic designs, but the basic principle for prevention is the same: stop heat from reaching the underside of the roof and melting snow.
Read our full white paper on proven ice dam prevention strategies to learn how your home can be ice dam free.
White Paper: Retire the Roof Rake: Proven Ice Dam Prevention Strategies (Adobe Reader required)