Roof
Covering, underlayment, flashing at every penetration and junction, and the ventilation that keeps the assembly dry. In Ontario, ice damming at the eaves is a recurring winter failure mode driven as much by attic heat loss and ventilation as by the roof covering itself.
Can you do your own roof work in Ontario?
Technically permitted in many cases, practically a bad idea. Fall risk aside, the parts that fail are the flashing details, which are also the parts hardest to get right without experience.
Authority: Your municipal building department · Source: 2024 Ontario Building Code (O. Reg. 332/12 (2024 edition)) · Reviewed 2026-09-10
Can you work on it yourself?
Technically permitted in many cases, practically a bad idea. Fall risk aside, the parts that fail are the flashing details, which are also the parts hardest to get right without experience.
If your ice damming is severe, the roof covering may not be the actual problem — attic insulation and ventilation often are. A roofer who only quotes shingles has not diagnosed anything.
Authority Your municipal building department
How long it lasts
Asphalt shingles commonly 15–25 years depending on grade and exposure; metal considerably longer. Flashing often outlives one covering and fails during the next.
What failure looks like
- Granule accumulation in gutters
- Curling, cupping, or missing shingles
- Staining on ceilings or at the top of exterior walls
- Ice damming at the eaves in winter
- Daylight visible in the attic, or frost on the underside of the sheathing
Worth knowing about your own house
- Is the underlayment and flashing being replaced, or only the shingles?
- Is the attic ventilation adequate, and was it assessed?
- How many layers are currently up there, and is anything being torn off?
Sources and review
Reviewed Reviewed 2026-09-10 Next review 2027-09-10 Tier C · 365-day SLA Reviewer: Justin Challenger