An ice dam is one of those problems that looks like winter just being winter, right up until the water shows up on your ceiling. The ridge of ice along the eaves is a sign of what is happening higher up on the roof, and it is worth understanding before a January thaw finds a way inside.

We are W Contracting Roofing, a Saskatoon roofing company, and stopping ice dams is part of how we detail a roof.

Ice dams are common on Saskatoon homes because our winters give them everything they need: snow that sits for months, and a stretch of warm days and cold nights that melts and refreezes it over and over. Here is what is actually going on, how to catch it early, and what keeps it from coming back.

What an ice dam actually is

Snow lands on the roof and stays. Heat leaking up from the house warms the roof deck under that snow, so the underside of the snow melts even when it is cold out. The water trickles down the slope until it reaches the overhang past the exterior wall, which stays as cold as the prairie air because there is no heated room beneath it.

There the water refreezes, and a ridge of ice builds along the eaves. Once that ridge is in place, the next round of meltwater pools behind it with nowhere to drain, and standing water on a roof does what standing water always does: it works its way under the shingles and into whatever is below.

Why Saskatoon roofs get them

A long prairie winter keeps a snow load on the roof for months at a time, and the swing between a sunny afternoon and a forty below night is exactly the melt and refreeze cycle a dam feeds on. Older homes tend to leak more heat into the attic, which makes the roof deck warmer than it should be. North-facing slopes, valleys where two roof sections meet, and the stretch above a warm room like a bathroom or kitchen are the usual spots to watch.

Older homes and newer homes get them for different reasons

SGI CANADA, which insures homes across Saskatchewan, calls ice dams a common problem in older homes and says newer homes can be at risk too. Where the heat escapes is usually what differs.

An older house in a neighbourhood like City Park or Nutana tends to have thinner attic insulation and more gaps around old wiring, chimneys and plumbing stacks. A storey-and-a-half home is harder again, since the upstairs rooms sit right under the roof deck with little space left for insulation.

Newer builds in Rosewood, Aspen Ridge or the newer parts of Warman and Martensville usually start out better insulated. Their weak spots tend to be the roof shape, with valleys that hold snow and bonus rooms over the garage that warm the roof right above them, plus roof vents that disappear under a drift.

How to spot one before it leaks

You can see most of the warning signs from the driveway. Look for a thick band of ice along the eaves, large icicles hanging off the gutters, and eavestroughs packed solid with ice.

Inside, a damp patch or a brown stain on a top-floor ceiling, or on the wall just below the eaves, means water is already getting past the roof, and SGI CANADA lists new ceiling stains as a warning sign too. If you can get into the attic safely, frost on the underside of the sheathing or damp insulation near the eaves is the same story told from the other side.

A quick ice dam check you can do from the ground

Walk around the house after a heavy snowfall, then again after a mild spell. SGI CANADA's guide to spotting and preventing ice dams adds a few signs to the ones above.

  • Dark or dirty-looking icicles

    SGI CANADA explains the colour comes from water that got into the attic, picked up dirt and ran back outside.

  • Snow melting unevenly

    Compare your roof with the neighbours' roofs on the same street. If yours has bare patches that theirs do not, heat may be getting out at that spot.

  • Water running down windows or doors

    Seeing this in the middle of winter is on SGI CANADA's list of warning signs, along with new stains on the ceiling.

  • Buried roof vents

    Snow can cover or plug roof vents, turbine vents (whirlybirds) included, which makes the whole problem worse.

Take a photo of anything you notice and keep the date. If a leak shows up later, it tells a roofer where to start looking.

The real fix is heat and air, not the roof

It is tempting to treat an ice dam as a roof problem, but most of the time the roof is doing its job and the attic is the culprit. Warm air escaping through a poorly sealed attic hatch, gaps in the insulation, or a bathroom fan venting into the attic heats the roof deck and starts the melting, and older homes in City Park or Nutana tend to have more of those gaps.

Keeping the attic cold and well ventilated so the roof deck stays the same temperature end to end is what stops the snow from melting unevenly in the first place. It is quieter work than it sounds, and it is usually where a recurring dam gets solved for good.

Where warm air gets into the attic

SGI CANADA names the usual culprits: exhaust fans, air ducts, chimneys, attic hatches and pipes that run into the attic. When the seal around one of them fails, warm air slips past it and heats the roof deck.

  • The attic hatch. One with no weatherstripping and no insulation on top leaks warm air every time the furnace runs.
  • Bathroom and kitchen exhaust fans that dump into the attic instead of venting outside, the first item on SGI CANADA's list.
  • Gaps where plumbing stacks, ducts and the chimney pass through the top-floor ceiling.
  • Some older pot lights in a top-floor ceiling, which can let heat straight up.

If you are comfortable going into the attic, check it on a cold day for frost on the nail tips or the underside of the roof boards. SGI CANADA's advice is to check those seals yourself and reseal them, or hire a professional to do it.

What clean eavestroughs have to do with it

When the eavestroughs and downspouts are full of leaves or already iced up, meltwater sits at the edge of the roof and freezes faster, so clearing them out in the fall is one of the simplest things that helps. If your eavestroughs, soffit and fascia are sagging, undersized or pulling away from the house, they will keep feeding the problem until they are put right.

What not to do

Do not climb up and chip at the ice with a hammer, an axe or a garden spade. It feels productive and it wrecks the shingles underneath, which turns a January nuisance into a spring repair.

Do not pour rock salt straight onto the roof either, since it stains the shingles and runs off into the plants below, and do not get onto an icy, sloped roof at all. From the ground, a roof rake used gently to pull the snow off the lower few feet takes away what the dam feeds on, and that is as far as it is worth going on your own.

How to use a roof rake without making things worse

SGI CANADA says the simplest way to prevent ice dam damage is removing snow from the roof, especially within two metres (six feet) of the eaves. A roof rake on a long pole does that from the ground.

  1. Stay on the ground, and keep the pole well away from the power line running to the house.
  2. Pull the snow down the slope, the same way the shingles lie, across the two metres nearest the eaves that SGI CANADA points to. Dragging it sideways can catch shingle edges.
  3. Leave a thin layer of snow on the shingles rather than scraping down to them.
  4. Shovel what comes down at least two metres from the foundation, as SGI CANADA recommends, so it does not melt into the basement.
  5. Leave solid ice where it is.

What to watch for through the year

Most of what stops an ice dam happens before the snow flies. Here is what matters in each part of a Saskatoon year.

  • Fall

    Clear the eavestroughs and downspouts once the leaves are down, and look at the attic hatch and roof vents before it turns cold. It is also the easiest time to get worn shingles or loose flashing fixed, with no snow in the way.

  • Early winter

    After the first real snowfall, walk around the house and watch how it melts. Uneven melting this early is a clue about warm spots in the attic.

  • Mid-winter thaws

    SGI CANADA says ice dams form when the weather swings from extreme cold to milder days. Keep an eye on the Environment Canada forecast for Saskatoon, and if there is a lot of snow on the roof, rake the lower edge before the warm days arrive.

  • Spring melt

    Check top-floor ceilings, the walls under the eaves and the attic insulation near the eaves for damp spots. Shingles that sat under a dam all winter are worth a look once the roof is clear.

If water gets in: what to photograph for your insurer

SGI CANADA notes that not all insurance policies cover ice dam damage. If a dam does cause damage, their advice is to do what you can to stop it getting worse and call your broker as soon as possible. Good photos make that call easier.

  • The ice ridge and icicles along the eaves, shot from the ground, plus one wider photo showing which side of the house it is on.
  • Every stain, drip or paint bubble inside, up close and from across the room.
  • Wet insulation or water in the attic, taken from the hatch if you can get there safely.
  • Anything you did to stop the damage getting worse, as SGI CANADA advises, like a bucket under a drip or furniture pulled out of the way.
  • Damaged belongings, before any of it goes to the curb.

Keep the dates with the photos. On a free inspection we photograph and video what we find on the roof, and our roof insurance claims page explains how we work alongside your adjuster.

When to call a roofer

Call when water is already coming inside, when the same dam builds in the same place every winter, or when a leak keeps returning after a cold snap. Our Saskatoon crew can trace where the water is actually getting in, which is rarely right under the stain, and handle the roof repair for damaged shingles or failed flashing.

If the roof turns out to be worn past the point where a patch makes sense, we will talk through roof replacement honestly rather than push you into one. Water coming in during a storm or overnight is covered in our emergency roof leak steps.

Questions to ask a roofer about ice dams

A roofer should be able to explain in plain words what is causing your ice dam. These are fair questions to ask anyone who looks at it, us included.

  • Is the water coming through a flaw in the roof, or is heat from the attic the real cause?
  • Can you show me photos of what you found up there?
  • Are the roof vents and soffit vents open and moving air?
  • What is under the shingles along the eaves and in the valleys? If the roof is being replaced, ask what leak barrier goes in those spots.
  • Does this need a repair, or is the roof worn enough that replacing it makes more sense?

For a leak that needs fixing now, our Saskatoon roof repair page has the details. If the roof is near the end of its life, start with roof replacement in Saskatoon.

Ice dam questions from Saskatoon homeowners

What causes ice dams on a roof?

Heat escaping into the attic warms the roof deck and melts the snow sitting on it. That meltwater runs down to the cold overhang at the eaves, where the next cold prairie night refreezes it into a ridge of ice.

More water backs up behind the ridge, and because it has nowhere to drain it works its way under the shingles and into the roof. It is really a heat and airflow problem in the attic, not a fault in the shingles themselves.

Can I remove an ice dam myself?
You can safely pull snow off the lower edge of the roof with a roof rake from the ground, which SGI CANADA calls the simplest way to prevent ice dam damage. Do not chip at the ice with a hammer or axe and do not climb an icy roof, because both damage shingles and put you at real risk of a fall. If a dam has already caused a leak inside, that is the point to call a roofer rather than keep working at it.
Do ice dams mean my roof is bad?

Not on their own. A roof in good shape, even on a newer build in Rosewood or Aspen Ridge, can still form an ice dam if the attic is losing heat and the eavestroughs are packed.

The damage comes from the water that backs up behind the dam, so a roof that already has worn shingles or tired flashing is far more likely to leak when it happens. An inspection tells you which situation you are in.

How do I stop ice dams from coming back?
Keep the attic cold and the roof draining by sealing the spots where warm air leaks into the attic, making sure the insulation and ventilation are doing their job, and clearing the eavestroughs and downspouts in the fall so meltwater has somewhere to go. Where dams keep forming in the same valley or over the same room, it is worth having someone look at what is warming that section.
Does home insurance cover ice dam damage in Saskatchewan?
It depends on your policy. SGI CANADA says not all policies cover damage caused by ice dams and suggests asking your broker about coverage ahead of time. If a dam does cause damage, stop what you can, take photos and call your broker as soon as possible.
Do you charge to look at an ice dam or a roof leak?

No. Our inspections are free and come with no obligation.

If water is getting in, we trace it back to where it started, document what we find with photos and video, and give you a straight answer on the repair. We are based in Saskatoon and answer the phone Monday to Saturday, 8 to 6.