Ice Damming Ottawa

What is an ice dam?

An ice dam happens when ice forms at the edge of the roof and prevents melting snow from draining off. When water backs up behind this dam, it can leak into your home and cause damage to your walls, ceilings, insulation and more.

What Causes Ice Dams in Ottawa?

One reason is weather related.

When major snow falls occur, they can insulate the attic and warm the air inside. This causes the snow on the roof to melt. The water is then absorbed into the layer of snow – forming ice. Water can then run down underneath to the colder points of the roof and form ice dams. Others are related to the house itself such as thermal bridging through walls, air leaking and pot lights.

Thermal bridging through walls

Older homes can have insufficient insulation issues that can put them at risk for ice dams. This can happen at where the roof and walls meet. Heat from the home can be transferred through the framing to the roof deck and melt the snow. The water then flows down under the snow to overhangs where it freezes again.

Air leaking

Home owners can experience a significant amount of heat loss through the walls and ceiling as it is transported by the air, which warms the attic and causes similar melting processes to occur leading to ice dams.

Pot lights

Sealing pot lights properly is difficult. Though they don’t generate a great deal of heat, they do heat the air, which can contribute to the problem.

Why it matters to you

Moisture in your home can lead to dangers to your health.

When ice dams form on your house, it allows moisture to enter the home – leading to mold and mildew growth. Mold and mildew can result in serious respiratory problems.

What you need to do

1. Fix the water source issue(s)
2. Clean affected areas to maintain air quality
3. Dry any parts of the house that are wet or damp to prevent mold and mildew growth.