When most Calgary homeowners think about asbestos, they picture attic insulation, popcorn ceilings, or old floor tiles inside the house. What often gets overlooked is the exterior. For decades, asbestos was added to a range of outdoor building products because it was cheap, fire-resistant, and durable. If your home was built before the early 1990s, the siding, roofing, and cement board on the outside may deserve just as much attention as anything indoors.
Why Asbestos Was Used Outside the Home
Asbestos was banned in Canada in 2018, but before that it was valued for the same qualities that made it useful inside: resistance to heat, weather, and rot. Manufacturers mixed asbestos fibres into exterior products to make them stronger and longer lasting. On older Calgary homes, that legacy can show up in several places.
Common Exterior Materials That May Contain Asbestos
- Cement asbestos siding (sometimes called transite), often in shingle or panel form
- Roofing shingles and felt on older roofs
- Soffits, fascia, and cement board used as trim or backing
- Stucco and exterior coatings applied in older eras
- Window putty and caulking around older frames
These materials are usually safe while they remain intact and weathertight. The risk appears when they crack, break, or are cut, drilled, or torn off during a re-side, a re-roof, or a demolition.
The Weathering Problem Unique to Calgary
Calgary’s climate is hard on exterior materials. Freeze-thaw cycles, hail, and strong winds can crack and erode siding and shingles over the years. As older asbestos-containing materials deteriorate, they can begin to release fibres, and a hailstorm that shatters brittle cement siding can turn a stable material into a hazard. This is why exterior asbestos should never be assumed harmless simply because it is outdoors.
Do Not Cut, Pressure-Wash, or Rip It Off
The single most important rule with suspected exterior asbestos is to leave it undisturbed until it has been tested. Homeowners sometimes power-wash old siding, saw through panels during a renovation, or tear off shingles themselves, all of which can send fibres into the air and across the yard. Even outdoors, disturbed asbestos is a genuine health risk to you, your family, and your neighbours.
Before any exterior renovation on an older home, confirm what you are working with. YYC Asbestos Removal & Renovation provides certified testing that identifies whether exterior materials contain asbestos, so you can plan a re-side or re-roof safely. If your home’s age already puts it in the higher-risk category, our overview of how a home’s age increases the risk of hidden asbestos is a useful starting point.
How Professional Removal Protects Your Property
When exterior asbestos does need to come off, professional abatement follows strict procedures to contain fibres and protect the surrounding area. That includes controlled removal techniques, proper protective equipment, careful handling to avoid breakage, and disposal that follows provincial guidelines. Doing it right the first time prevents contamination of your soil, your home, and neighbouring properties.
The team at YYC Asbestos Removal & Renovation handles exterior abatement with the same rigour applied to interior work. Because the same certified crew manages testing through to removal, nothing falls through the cracks between identifying the material and safely getting rid of it. You can read more about our approach on the asbestos abatement page.
Planning an Exterior Renovation the Right Way
If you are considering new siding, a roof replacement, or exterior demolition on an older Calgary home, sequence the work correctly:
1. Test first so you know exactly what is on the building.
2. Plan around the results, budgeting time for abatement if needed.
3. Use certified professionals for removal of any confirmed materials.
4. Confirm disposal is handled according to provincial rules.
5. Then bring in your siding or roofing crew to complete the new work.
Following this order keeps your trades safe, avoids stop-work surprises, and ensures the finished project is genuinely clean rather than just covered over.
Frequently Asked Questions
How can I tell if my siding contains asbestos?
You cannot tell reliably by looking. Cement asbestos siding can resemble ordinary fibre-cement or composite products. Only laboratory analysis of a properly collected sample can confirm it.
Is it safe to leave asbestos siding on my house?
If the material is intact, sealed, and not deteriorating, it may be stable. Problems arise when it is damaged, weathered, or disturbed by renovation. Testing helps you decide whether to manage it in place or remove it.
Can I re-side over old asbestos siding instead of removing it?
Sometimes encapsulation or covering is an option, but it depends on the material’s condition and your plans. A certified professional can advise whether removal or management in place is appropriate for your situation.
What about the disposal of exterior asbestos waste?
Asbestos waste must be handled and disposed of according to Alberta’s provincial guidelines. Professional abatement includes proper bagging, labelling, and transport to an approved facility.
Get Clarity Before You Start
Exterior materials are an easy blind spot, but on an older Calgary home they can carry the same risks as anything inside. Before you re-side, re-roof, or tear anything off, let YYC Asbestos Removal & Renovation confirm what you are dealing with. Call +1 403.390.5581 for a free assessment and renovate your home’s exterior with confidence.