In Airdrie, ice dam season doesn’t follow a neat calendar. A snowfall in November, a chinook that pushes the temperature well above freezing, then a hard cold snap — and by morning there’s a ridge of ice along the roof edge and a row of icicles down the wall. Repeat that cycle a few times and the ice builds in layers. The short version of why it happens: heat escaping into the attic melts roof snow from below, and the water refreezes over the cold overhang. The ice dam removal page explains the mechanics in detail. This article is the practical side — a checklist you can work through before, during and after winter so you’re dealing with as few dams as possible.
Before winter: the fall checklist
The best time to deal with ice dams is September and October, when the attic is comfortable to work in and the roof is dry. Most of what prevents ice dams happens inside the house, not on the roof.
1. Find and seal attic air leaks
Warm, moist air from the house leaking into the attic is the biggest single driver of ice dams on Airdrie homes. On a cool fall evening, go up to the attic with a flashlight and look for:
- The attic hatch. Is there weatherstripping around it? Is the hatch itself insulated on top? An unsealed hatch in a hallway ceiling is a common leak point.
- Pot lights. Recessed lights in the top-floor ceiling often leak air around the housing. Look for dirty or discoloured insulation around them — dust in insulation is a sign air has been flowing through it.
- Plumbing stacks, wiring holes and duct penetrations. Gaps where pipes and wires come up through the top plates of walls.
- Chimney and furnace flue chases in older homes.
Small gaps can be sealed with caulk or low-expansion foam; anything around a flue or a light fixture needs the correct fire-rated product. If you’re not comfortable working in the attic, this is a job worth paying for — it’s usually the most effective prevention step there is.
2. Check your insulation
Look at the depth and condition of the insulation, especially near the outside walls, where dams usually start. Thin spots, bare patches where someone walked or stored boxes, and insulation that’s matted or discoloured all let more heat through to the roof deck right above the eaves.
3. Follow every bath fan duct
Trace each bathroom fan duct to where it exits. It should connect firmly to a roof or wall cap and carry air outside. A duct that has fallen off, sags into the insulation or simply ends in the attic sends warm, wet air straight up under the roof deck every day. That moisture becomes frost in January and drips through the ceiling in the next chinook.
4. Make sure the intake vents under the eaves are clear
Look along the outside walls from inside the attic. You should be able to see daylight or clear baffles near the eaves where the intake vents are. If insulation is packed tight against the roof deck there, the attic can’t pull in cold air, and the lower roof warms up. From outside, glance at the intake vents under the eaves and make sure they aren’t painted over or blocked.
If intake and exhaust seem unbalanced — for example, few intake vents, or several different styles of exhaust vent on the same roof — it’s worth having it assessed. The roof ventilation page explains how proper venting is calculated; for reference, Alberta’s building code calls for at least 1 square foot of vent area per 300 square feet of insulated ceiling, split between intake and exhaust.
5. Buy a roof rake before you need one
A roof rake is a long-handled tool with a wide plastic or foam head that lets you pull snow off the lower part of a roof while standing on the ground. Buy it in the fall. After the first big snowfall they can be hard to find. Choose one with extension poles long enough to reach at least the first few feet above your eaves, and a head that won’t scrape the shingles.
6. Look at the roof edge itself
From the ground, check the lower edge of the roof for shingles that are lifted, cracked or missing, and for any metal edge that’s bent. Damage there lets meltwater in more easily once a dam forms. If you had ice dams last winter and never had the edge checked, fall is the time.
During winter: what to watch for
Once the snow arrives, your job is mostly to watch — and to act early from the ground.
Watch after every chinook
The riskiest time in Airdrie is the day or two after a chinook, when roof snow has been melting and the temperature drops again. Walk around the house and look for:
- Icicles forming along the roof edge, especially large or thick ones. A few small icicles aren’t a problem; a solid row, or icicles that keep growing day after day, means water is running off a warm roof and refreezing.
- Uneven melt patterns. On a snowy roof, bare patches or stripes where snow has melted over the attic — while the rest is still covered — show you exactly where heat is escaping.
- A ridge of ice building at the eaves, with snow still sitting above it.
- Ice on the wall below the roof edge or around windows.
Take photos of what you see. They’re useful for pinpointing problem areas later, and for your insurer if water ever does get in.
Rake the lower roof — from the ground
After a heavy snowfall, use your roof rake to pull snow off the lowest 3 to 4 feet of the roof above the eaves. Removing that snow takes away the fuel for a dam. Work from the ground, stay clear of the snow sliding off, keep well away from power lines, and don’t try to scrape down to bare shingles — leaving a thin layer protects the roof surface.
For low-slope sections, roofs you can’t safely reach, or snow loads that feel too big to handle, a professional roof snow removal is safer than a ladder.
Check inside, too
Ice dams show up indoors before most people notice them outside. On a regular basis during winter:
- Look at ceilings along exterior walls on the top floor for new stains
- Check around windows on the upper floor for water or peeling paint
- Pop your head into the attic on a cold morning and look for frost on nail tips or the underside of the roof deck
What NOT to do
It’s tempting to take matters into your own hands. Please don’t:
- Don’t chip or hammer the ice. Axes, hammers, ice picks and shovels break shingles and puncture the membrane beneath them. The repair often costs more than the removal would have.
- Don’t use salt on the roof. Rock salt damages shingles, corrodes metal flashing and kills plants and lawn below. Salt-filled socks or pucks laid on the ice cause the same problems.
- Don’t climb onto a snowy or icy roof, or set a ladder on ice. Winter ladder falls are one of the most common ways homeowners get seriously hurt. No ice dam is worth it.
- Don’t use a pressure washer or a torch. High-pressure water strips granules and drives water under shingles; open flame near a roof is a fire risk.
If water comes in
If a dam is already pushing water into the house, put down towels and buckets, move valuables, and photograph everything. Then call for professional removal — steam equipment melts channels through the ice without damaging the shingles. The ice dam removal service covers what that involves. As a rough guide, clearing a single dam along one edge of a bungalow typically runs around $400–700, with larger or multi-edge jobs on two-storeys more commonly $800–1,300 (2026 Airdrie market estimates — actual cost depends on the amount of ice and the roof).
After winter: the spring follow-up
Heavy, wet snow in March and April can keep ice dam season going longer than people expect. Once the roof is fully clear, do a follow-up — especially if you had dams or any leaks.
From the ground
- Look for shingles along the roof edge that are lifted, cracked or missing, where ice may have pried them up
- Check the metal edge and flashing for bends or gaps
- Note any shingles on the lawn or driveway
From the attic and inside
- Look for water stains on the roof deck near the eaves
- Check insulation along the outside walls for wet, matted or mouldy patches
- Look for dark spots on the sheathing that could be mould
- Re-check the ceilings and walls where stains appeared during winter — are they dry now?
Book an inspection if you had serious dams
Ice that sits on a roof edge for weeks can soften the decking and damage the underlayment, and none of that is visible from the ground. If you had a thick dam, a leak, or dams in the same spot winter after winter, book a spring roof inspection once the melt is done. Finding soft decking in April is far better than finding it with next winter’s first leak.
Plan the permanent fix
Spring and summer are the right time to fix the underlying causes: air sealing, topping up insulation, and balancing ventilation. A ventilation correction on a typical Airdrie home is often in the $400–900 range (2026 Airdrie market estimates), which is frequently less than two winters of repeated ice dam removal. If the roof is due for replacement anyway, make sure the new one includes ice-and-water shield running well up from the edge and in the valleys.
Your ice dam season checklist at a glance
Fall (September–October)
- Seal attic air leaks: hatch, pot lights, penetrations
- Check insulation depth, especially over outside walls
- Confirm every bath fan duct vents outside
- Clear intake vents under the eaves
- Buy a roof rake with enough reach
- Check the roof edge for damage
Winter (November–March)
- Walk around the house after every chinook
- Watch for growing icicles and uneven melt
- Rake the lowest 3–4 feet of roof after heavy snow, from the ground
- Check top-floor ceilings and the attic for moisture
- No chipping, no salt, no climbing
Spring (April–May)
- Check the roof edge, metal edge and flashing
- Look for stains and wet insulation in the attic
- Book an inspection if dams were serious
- Plan air sealing and ventilation fixes for summer
A final word
Ice dams are a symptom, not a mystery. A cold attic with a well-sealed ceiling, good insulation and balanced ventilation will still see snow and chinooks, but it won’t build thick ridges of ice at the roof edge winter after winter. The fall checklist does most of the work; the winter and spring steps catch what’s left.
If you’d like a second set of eyes on your attic or ventilation before the snow flies, you can request a free estimate — it’s a no-pressure way to find out whether your home is set up for winter.