How long should your roof last here?
Manufacturer brochures quote lifespans from continental averages. The Fraser Valley is not that: six months of rain, heavy tree shade, freeze-thaw snaps and aggressive moss. Here are the honest numbers for our climate.
Service life in coastal BC conditions.
| System | Brochure life | Real life here |
|---|---|---|
| 3-tab shingle (older stock) | 20 to 25 years | 12 to 18 years |
| Architectural shingle | 30 to 50 years | 22 to 30 years |
| Premium polymer-modified shingle | Lifetime | 25 to 35 years |
| Cedar shake | 30+ years | 20 to 28 years with treatment; less without |
| Enviroshake composite | ~50 years | ~50 year design life holds up |
| Metal standing seam | 50 years | 50+ years, fasteners never age out |
| Torch-on two-ply | 25 to 30 years | 25 to 30+ when detailing was done right |
The pattern: subtract roughly a third from brochure numbers for our rain, shade and moss pressure, unless the system has nothing organic for biology to eat.
The four local killers.
- Moss. Roots into shingle laps, lifts edges, holds water against everything. The single biggest lifespan factor under mature trees.
- Shade and damp. North slopes under cedars stay wet for days after rain. Wet asphalt ages several times faster than dry.
- Freeze-thaw. Water in a lifted tab or cracked flashing freezes, expands, opens wider. Our snap-thaw cycles exploit every small defect.
- Attic ventilation problems. A roof cooks from below in summer and condenses in winter when intake and exhaust are wrong. This is why we check the attic on every inspection.
Three things worth doing.
- Gutter cleaning twice a year, spring and fall. Standing water at eaves finds its way back up under shingles.
- Moss treatment before it's established, not after. Once moss has rooted laps, cleaning does cosmetic damage.
- A roof inspection every few years after year ten. Flashing renewal and targeted repairs bought early cost a fraction of premature replacement.
My shingle warranty says lifetime. Why replace at 25?
Manufacturer warranties cover material defects, not wear-out. They also prorate sharply after the first decade and require proof of proper installation and maintenance. Treat "lifetime" as marketing with legal fine print.
Does cleaning moss damage shingles?
Aggressive pressure washing does, badly. Proper treatment uses moss-specific applications and gentle removal. If moss has already rooted the laps deeply, replacement math beats cleaning math.
Do metal roofs really last 50 years here?
Standing seam, yes. The steel and coating easily outlast 50 years in this climate; what fails elsewhere is exposed screw washers, which standing seam eliminates by design.
Is cedar still worth it in this climate?
For heritage character where the look matters, yes, with eyes open: budget moss treatment every couple of years and plan replacement around year 25. Enviroshake delivers the look without that contract.
How do I know my roof's real remaining life?
Granule loss in gutters, curling tabs, brittle shingles at eaves, daylight in the attic, past repairs clustering. An inspection on the roof reads all of it in half an hour.
Wondering which roof you have? We'll tell you straight.
A real conversation with a local roofer. No pressure and no obligation, just honest advice about your roof.