New Roof..? Old Roof..? What Actually Causes Ice Dams?


Many people believe that ice dams are directly related to issues with the roof. Unfortunately, whether you have a newer roof or an older roof the formation of an ice dam has nothing do with the construction of the roof. Ice dams and the leaking they cause indicate the attic is too warm.

Then how can you solve ongoing ice dam occurrences?

  • The most effective way for properties to address ice dam issues is to have a qualified insulation company come in and review the attic spaces.

What will they look for?

  • They will check for the proper amount of insulation and appropriate distribution.
  • They will also assess if there is an adequate amount of intake soffits around the property (i.e. vented soffit panels).
  • Sometimes the vented soffit panels have been installed, but the plywood in the soffit was never cut out. Meaning the holes in the soffit panel is not doing anything because there is a solid piece of wood behind it.
  • Another common problem with intake ventilation is that insulation has been blown in and is blocking the intake vents or has crushed the chutes designed to create a passage for air through the ventilation. 

All of the above issues are often serviced by companies who specialize in attic insulation and ventilation services.

If these items check out, then the next step is to consider installing a heat cable in the vulnerable areas (usually eave lines, valleys, gutters and downspouts).  As long as the heat cable is kept in good working condition and is turned on for the appropriate interval at the correct times, ice dam issues should be minimized if not eliminated completely. 

There are also professionally installed systems that have sensors that can turn the system off and on for you.

If for some reason installing heat cables is not a feasible option, the most practical preventative measure is to diligently remove the snow from the roof as soon as possible after it falls.  The snow must be removed before the ice dam forms.

When water becomes static and starts to accumulate it can easily defeat even high quality, correctly installed roof components and can cause leaks in the property.  If this is a persistent problem for any property then a little prevention will go a long ways in controlling if not eliminating the expensive nuisance.