Ice Dam Removal: The Basics
In Northern Michigan, we’re accustomed to dealing with everything that Mother Nature throws at us, especially come wintertime. Snow accumulation and ice build-up can present serious issues that need to be dealt with, and ice dams are no exception.
What is an Ice Dam?
An ice dam is a build-up of ice along the lower edges of sloped roofs. The formation of an ice dam causes meltwater to back up on the roof and often leads to water leaking into the structure under roof shingles.
Most ice dams can be identified by visually inspecting the exterior roof line of a building. However, some other signs of ice dam issues include:
- Large icicles on exterior of structure
- Water in attic along roof rafters and/or ceiling joists
- Wet interior walls/ceilings
- Water present in windows/doorways
- Water leaking from light fixtures in ceilings
How Do Ice Dams Form?
There are three main conditions that allow ice dams to form:
- Heat loss through the roof
- Snow cover on the roof
- Freezing temperatures outside
In most cases, ice dams form when warm air from inside the structure moves through the roof, due to insufficient roof/attic insulation, and causes the lower layer of roof snow to melt, with the upper snow acting as an insulator. This meltwater moves down the roof and freezes as it meets the outside, freezing air. The ice continues to build up, creating the structure of the ice dam (see illustration).
Ice dams most frequently form along the lowest edge of the roof, in roof valleys, along dormers, and near elements such as vents, discharge pipes, and chimneys. On shallow-pitched roofs, an ice dam of just 1-2″ can cause problems.
What Kind of Damage Can Ice Dams Cause?
Ice dams can cause many issues on the inside and outside of a structure. These issues include:
- Water leaking into the structure and soaking the insulation and drywall/plaster
- Mold and mildew growth due to moisture being present in walls/ceilings
- Water staining and paint damage to finished surfaces inside the structure
- Electrical shorts if water reaches outlets, light fixtures, or switches
- Damage to exterior gutter systems
- Structural damage to eaves due to the added weight of ice build-up
How Can Ice Dams Be Removed?
The most effective way to remove existing ice dams is through the power of steam! U.P. Ice Dam Removal uses specialized equipment to gently break apart built up ice with low-pressure steam, while avoiding any damage to roof shingles.
Several other methods have been used to remove ice dams, but each has their own drawbacks. Breaking apart ice dams with blunt force (hammer, axe, etc.) is dangerous and will often lead to a damaged roof. High pressure sprayers (hot or cold) add more water to the area and can reduce the life of the shingles by removing the protective coating of grit. Additionally, they can lead to holes in shingles due to the focused stream of high pressure water. “Salt socks” and roof melt tablets use calcium chloride salt to melt the ice and create a channel for water to escape. This method can be effective in a pinch, but it’s temporary and introduces corrosive chemicals to the site.
Steam is the Safest and Most Effective Method of Removing Ice Dams!
How Can Ice Dams Be Prevented?
As with most problems, ice dam prevention is the best solution. The best way to prevent ice dams is through proper roof ventilation and insulation. Consider reaching out to a licensed contractor to discuss this option (http://www.upbuilders.org/q/member-directory). The next best option is to continually remove snow from the roof throughout the cold season, thus not allowing ice dams to form. In some cases, properly installed electric de-icing cable can be effective in preventing ice dam formation if other methods are not feasible.