Tuesday, December 8, 2015

Preventing Ice Damns This Winter...

As winter continues to set in, we must take appropriate measures to protect our home against the freezing temperatures.  We all know about the common chores; turning off water flow to outside faucets, having our heating system checked and serviced, cleaning the gutters etc.  But have you ever thought to take the appropriate steps to protect against ice dams?

First, lets define what exactly an ice dam is:

An ice dam is a ridge of ice that forms at the edge of a roof and prevents melting snow (water) from draining off the roof. The water that backs up behind the dam can leak into a home and cause damage to walls, ceilings, insulation, and other areas.

This phenomenon typically occurs when attic temperatures become warm enough to support active snow melting from below.  As the snow melts, the water flows down the roof however becomes blocked at the eaves due to an accumulation of ice (the dam).  Since the water from the melting snow has no place to go, it now has the potential to back flow into the house. When this happens, damage will likely follow. This would include wood deterioration, roof sheathing damage, drywall damage, possible mold growth and the list goes on and on.  Typically this goes unnoticed until you see a water stain on the ceiling or other like damage.  By then...it's too late!

The challenge becomes figuring out the root cause of why an ice dam situation is occurring.   Unfortunately, the cause could be a series of issues that combine to create this problem.  That said, lets take a look at some common contributory causes:

  • Poor Attic Insulation - The lack of adequate insulation may allow for escaping heat from the conditioned portions of your house to enter into the attic space.  This alone can cause the attic temperature to rise and cause rapid snow melting to occur.  
  • Gaps and Penetrations - Kind of hand in hand with the above issue, gaps and penetrations into the attic space that are poorly sealed or poorly insulated may be the cause for heat escaping the house into the attic space.  This would include recesses or mounted lighting, ceiling fan penetrations, exhaust fans, attic access points etc.  
  • Poor Roof Drainage - If your gutters are poorly maintained i.e. clogged with debris or improperly sized for your roof, then water will not properly drain through the gutters and into the downspouts.

So now that we have a general understanding of this issue, let's look at some ways to help prevent ice dams:

  1. Consider a home audit to ensure your attic is properly insulated.  "R" values change as insulation becomes compacted, worn or breaks down over time.  Simply enhancement of attic insulation may be the key.
  2. Ensure your gutters have been cleaned and are free of obstructions and debris.  Since the fall is ending, now is a great time to get the leaves, twigs and other debris cleaned out.
  3. Check your home for poorly insulated gaps and penetrations.  A simple tip is to have someone blow a hair dryer or like device while you check for airflow from the attic side.  If you feel air passing through, then its likely that the penetration is poorly sealed.  A small about of spray foam insulation will help solve these types of problems.  Remember...it doesn't take much!
  4. Continue to monitor exterior conditions.  In some cases, you may have to physically remove the ice dam if possible.  If this is the case, use caution...you don't want to damage your shingles, gutters or fascia.