Ice Dams Are Simple To Understand
The key to comprehending the formation of an ice dam lies in basic roof construction. For this discussion, the roof consists of four layers.
1) Rafters support the roof.
2) The roof deck is nailed to the rafters.
3) The Underlayment covers the roof deck.
4) The shingles are nailed through the underlayment to the roof deck.
When snow covers the roof, problems may occur. If the roof deck is warmer than the outside air temperature, ice dams often form as described below.
1) The warmth from the roof deck causes the snow touching the roof to melt.
2) The water runs over the shingles, under the snow, and refreezes at the bottom of the roof.
3) This process continues, causing a large ice dam to build up.
4) The water behind the dam backs up under the shingles and causes a roof leak.
Ice Dams Are Preventable
In new construction, they should be virtually nonexistent. In existing homes, properly installed ridge and soffit vents should solve the problem. Roof rakes to remove snow and heating cables can also help eliminate them.
Ice Dams Can Cause Extensive Damage
You may not have a problem with ice dams in Forest Hills, NY, but water damage happens in many ways. Sometimes it happens quickly and is obvious. Other times it is slow and subtle. Ice dams usually form gradually. By the time you see a stained ceiling or crumbling plaster, the destruction may be significant. Affected areas may show up in many locations.
- Roof deck
- Lights and other fixtures
Ice Dams Are Manageable
Mitigating damage caused by them is usually not for the do-it-yourselfer. These problems need to be addressed quickly before mold establishes a foothold. The best solution is to bring in water damage repair specialists to do the job quickly and completely.