_____________________________________________________________________________________________________________________________________________
   
                                                                                                                      2007-2010 L.H Krueger and Son Inc.
ICE DAMS
Chances are, if you are looking at this, you need answers...and fast.

Ice Dams occur when snow accumulates on the roof of a house, melts and then
refreezes. If you have inadequate insulation and/or ventilation in the attic this is
likely the cause for the ice dam. Many older homes suffer from no soffit vents at
all as well as inadequate roof venting. Ventilation points between the soffit and
attic may be blocked entirely with insulation allowing no airflow to the attic at all.

Warm air coming up through the roof melts the accumulated snow.  The
resulting melted water flows down the roof, under the snow, onto the eave and
into the gutter. The eave and gutter aren't heated, so they are a naturally
cooler area where the colder temperature on the eave causes the melted snow
from above to freeze. Eventually, ice accumulates in the gutter and builds
backwards up the roof. Continued melting causes the size of this ice dam to
build until the water accumulating behind it has no where to go but under the
shingles.

Because of the complex interaction of climate, melting, freezing, and home
conditions it is possible for even a house that has no ventilation or insulation
issues to develop ice damming when there is extreme cold or heavy snow. A
house that has poor insulation/ ventilation will have ice dams during normal  
winter weather.

So How Do I Prevent Ice Dams?

Make sure the attic is properly insulated
Seal entrances and scuttle holes into the attic.
Provide proper ventilation to attic through gable and eave vents.
Make sure vents aren't blocked or filled with insulation.
Keep gutters clean.
Use Grace Ice and Water Shield under the shingles at the eaves. (What is
Grace Ice and Water Shield?)

But what if I have water leaking in my house?

Remove as much snow as possible with a roof rake (the bottom 3-5 feet is most
important).
A hose can be used on warmer days to melt the ice from the gutter up to the
ice dam. This will only help for a few days at best and can cause leaking into
the house (avoid if at all possible!).
Special services are available to steam the ice dams off, but this can be very
expensive.
Break Ice Dams by creating ice channels to drain water. Caution must be used
here to avoid roof and gutter damage.
Electric deicing cables can be used for areas that have persistent problems.
Follow manufacturer directions or have us do it for you! These cables need to
be in place prior to the icing to be effective.


Is there anything I shouldn't do?

Do not chop ice off the shingles. You are likely to damage the shingles and
possibly the gutters as well.
Some sources recommend nylons stockings with a chemical melting agent
inside tossed onto the roof. Take care that a downspout doesn't get plugged
by an errant stocking.
©