Category: Current Issue
 
caption, page 7:
 
Ice Dam
Snow on the unheated part of a roof turns to ice which sits in the gutter which forces melting snow from above to leak into the house. Linda Lemmon photo.
 
Ice dams:
Winter's
villain
By Linda Lemmon
Town Crier Editor
The equation is like a bad brumal penny: winter plus snow, plus cold, plus melting equals ice dams which equals stained ceilings, disintegrating plaster and, in general, gnashing of teeth.
Anatomy of an ice dam: The eaves of a house are cold, unheated. When snow builds up at the eave, in the gutters, it freezes and builds up, creating an ice dam. It's trouble when warm air from the home goes up through the ceiling to the roof and melts the snow cover there.
The snow melts and flows down the roof --- until it hits the ice dam. The water backs up and is forced under the shingles and the underlayment.
From there gravity takes over and the water flows through attic the insulation, flattening it and making it less energy efficient. It continues on its journey and flows into the wall cavity and onto the ceilings, soaking through to the interior.
Gnashing of teeth.
The culprit in this winter tragedy is the warm attic. If the attic were cold, if the air underneath the roof deck were cold, there'd be no melting on the roof and no "liquid fuel" for the ice dam.
Experts recommend insulation in the roof of at least R-38 and making sure that the ridge vent is functioning.
Special care should be taken for the biggest, most forgotten entry for warm air into the attic: the trap doors into the attic. There are insulation kits available for these.
And when the next winter season starts, experts recommend that every time it snows --- even if it's just an inch --- get out there with the roof rake. This will prevent an ice dam for even getting a start.
What to do with the current ice dam problem? 
Keep up with the roof raking to take away some of the "ammo" for the ice dam. Many pack old pantyhose legs with ice melt, attach a rope to it and swing it into place, perpendicular to the gutter near the downspout. This cuts a channel into the ice dam, allowing melting water a way to leave the roof. Do not use rock salt in the pantyhose.