Why did hail knock granules off my Panorama Hills shingles?

Granule loss from hail is one of the most common complaints after a Calgary storm, and it matters more than it looks.

What hail actually does to a shingle

Asphalt shingles are made of a fibreglass mat coated in asphalt and then embedded with mineral granules. Those granules do three jobs: they protect the asphalt from ultraviolet degradation, add fire resistance, and give the shingle its colour. When a hailstone strikes, it delivers a sharp impact that dislodges granules from the asphalt matrix. The larger and harder the stone, the more granules it knocks loose. Calgary sits in what the City of Calgary calls "hail alley," the part of Canada that sees the most hail, and the August 2024 storm alone generated roughly $2.8 to $3 billion in insured losses across the city. Panorama Hills, in Calgary's northwest, is fully exposed to the hail tracks that move through that corridor.

A few things make the damage worse on any given roof. Shingles that are already 10 or more years old have lost some of the adhesive bond holding granules in place, so the same storm hits them harder than a newer roof. Steeper pitches take a more glancing blow and tend to fare better than low slopes, which receive hail nearly straight on. The direction the roof faces matters too: a slope facing the storm's approach loses more granules than the sheltered side.

The reason granule loss is serious is that once the asphalt is exposed, UV breakdown accelerates quickly. A shingle that looks cosmetically damaged today can crack, curl and leak within a few seasons if the granule layer is gone over a significant area.

What to do next in Panorama Hills.

Start by checking your attic for any water stains or daylight, and look in your eavestroughs for a heavy accumulation of granules, which is a reliable sign of widespread impact damage. Photograph everything from the ground; do not walk the roof yourself after a storm.

Contact your home insurer before authorising any repair work. Standard home insurance covers hail damage, and the insurer will send an adjuster to scope the loss. A roofer's inspection report, with photos and measurements, helps you compare the adjuster's scope against what the contractor found. Be cautious of door-to-door offers in the days after a storm; confirm who the contractor is and whether your insurer referred them before signing anything.

If the claim proceeds, this is a good moment to ask your insurer about a Class 4 impact-resistant shingle. The City of Calgary says these shingles reduce the chance of hail damage roughly 15 times and save about $3 for every $1 of added cost over their life. A majority of insurers offer premium discounts of up to 50% for hail-resistant materials, though the exact figure varies by policy, so ask your own insurer directly.

For a full asphalt shingle replacement in Calgary, budget roughly $10,000 to $24,000 for a typical detached house, or $13,000 to $25,000 if you upgrade to Class 4 shingles. A like-for-like shingle replacement does not require a City of Calgary building permit.

A second set of eyes before the adjuster visits is worth having, and local roofers can inspect through a free match on this site.