The following potential causes or evidence of ice damming were noted during your inspection. Ice dams are a build-up of ice, generally at the roof's edge, which allows water to back-up under the roof coverings, causing leakage.
Evidence of previous ice damming.
- Roof covering/shingle damage caused by ice/snow removal.
- Excessive wear of roof coverings/shingles at the roof edge.
- Water stains or damage noted at soffits and exterior walls.
- Water stains or damage noted at interior ceilings/walls.
- Water stains or damage noted at roof sheathing/structure at roof edge, inside attic.
- Specialized roof components have been installed to attempt to prevent ice damming leakage.
- Heating cables have been installed at the roof.
- Ice dams present during inspection.
Potential causes of ice damming.
- Intricate roof design which may cause poor water drainage.
- 1 1/2 story houses and townhouses are susceptible to ice damming.
- Lower sloped/long sloped roof, allowing water time to freeze on roof.
- Insufficient insulation/ventilation of attic/roof spaces can promote snow melt on roof.
- Cathedral ceiling designs can reduce insulation or ventilation levels.
- Inefficient window/door seals allow heat to escape, facilitating snow melt on the roof above those components.
- Location of roof components (plumbing vents, skylights) may block/slow water drainage.
- Changes in roof slope will slow water drainage promoting ice build-up.
- Eavestrough downspouts discharging to lower roof can cause water back-up/leakage.
- Dirty/clogged eavestrough gutters and downspouts will slow water drainage from roof.
Recommended course of action.
- Your roof should be monitored closely for ice damming after heavy snowfalls.
- Proper insulation, ventilation and good roof maintenance can help reduce the risk of ice dam build-up.
- It is recommended that roof snow and ice build-up be removed to prevent leakage. This type of work should only be done by qualified professionals.