Snow is expected this weekend on Long Island and the NY Metro area and the Weather Service has issued a WINTER STORM WARNING for the area. Whenever there is snow, you are guaranteed to have troublesome ice dams to follow. Ice dams can cause major water damage and flooding to your home, which requires immediate attention.
As winter advances through cycles of freezing and thawing, buildings and homes experience ice buildup and roof damage. In general, ice dams are formed when attic heat moves up to warm the roof and melts snow at or near the ridge. Snow melts, runs downward and hits the edge of the cold roof, resulting in re-freezing snow. These cycles cause ice to accumulate and back up under shingles. Damage appears in the form of soaked insulation, stained, cracked and damaged sheet rock, damp, smelly, rotting wall cavities and stained, blistered and peeling paint.
Preventing Ice Dams
To prevent an ice dam, don't heat the roof, keep it cold. That way, the snow on the roof eventually dissipates without making large amounts of meltwater. The underside of the roof deck should not exceed 30 F. The best way to maintain low temperatures is by ensuring that there is adequate insulation and sealing gaps that let warm air pass into the attic from the house. The attic must also be ventilated, so that cold air is introduced into it and heated air escapes rapidly. Some remodeling contractors are under the impression that heat passing through the attic helps prevent ice dams, when just the opposite is true. Although excess heat moving from the attic through the roof rapidly melts snow, once the meltwater touches the cold eaves, it quickly freezes and forms an ice dam.
If you have a furnace in the attic, it may not be possible to prevent ice dams. Increased insulation, however, should help. First, insulate the areas between the roof rafters. It is important to keep an air space between the roof deck and the insulation in order to prevent a condensation buildup that can delaminate the roof deck. Prior to insulating, install polystyrene rafter air channels, which are available at home centers. Next, lay insulation blankets over the furnace's heating ducts to help reduce the heat buildup in the attic. If there's a hatchway into the attic, build a cover for it out of rigid poly-styrene insulation.
If the gable and ridge vents do not generate sufficient air movement to dissipate the heat, you will need a motorized vent at one end of the attic to exhaust the heat, and an adequately sized vent on the opposite end of the attic to draw in cold air from the outside.
Check your home carefully when ice dams form. Investigate even when there doesn't appear to be a leak. Look at the underside of the roof sheathing and roof trim to make sure they haven't gotten wet. Check the insulation for dampness. And when leaks inside your home develop, be prepared. Water penetration often follows pathways difficult follow. Don't just patch the roof leak. Make sure that the roof sheathing hasn't rotted or that other less obvious problems in your ceiling or walls haven't developed. And then detail a comprehensive plan to fix the damage. But more importantly, solve the problem.
If you experience water damage that requires a water damage/flood restoration expert, please contact Advanced Restoration at (800) 693-6263. Advanced Restoration is a full service property damage restoration company that can respond 24/7 to your water damage situation. We use state-of-the-art equipment to handle structural drying. Our professional staff is also available to handle mold situations that may occur as a result of a water loss. Our service area includes Nassau County, Suffolk County and the New York boroughs. Enjoy the snowfall and stay dry!