Moss on Your Vancouver Roof? Here's What to Do (and What to Avoid)

If you live in Metro Vancouver, you almost certainly have moss growing somewhere on your property — your roof, driveway, patio, or fence. It's one of our region's most persistent home maintenance challenges.

Why Moss Is a Problem

Moss isn't just cosmetic. On roofs, it causes real structural damage:

• Lifts shingles — Moss grows under shingle edges, lifting them and allowing water infiltration
• Retains moisture — A thick moss layer acts like a sponge on your roof, keeping it perpetually damp
• Accelerates deterioration — Trapped moisture breaks down roofing materials years faster than normal
• Adds weight — Wet moss is heavy, stressing your roof structure over time

The Right Way to Remove Roof Moss

DO: - Apply a zinc sulfate or moss-killing solution and let it work for 2-3 weeks - Gently brush off dead moss with a soft broom (working downward, not upward) - Install zinc or copper strips along the roof ridge to prevent regrowth - Schedule treatment in late winter/early spring when moss is actively growing

DON'T: - Pressure wash your roof — this destroys shingle granules and voids most warranties - Scrape moss off while it's alive and attached — you'll damage shingles - Ignore it — moss doesn't go away on its own in Vancouver's climate

Prevention Is Better Than Cure

After removal, prevention saves you from repeating the cycle:

• Zinc strips along the ridge line release zinc with each rain, inhibiting moss
• Trim overhanging branches to increase sunlight on the roof
• Annual inspection catches regrowth early when it's easy to treat
• Ensure good attic ventilation to reduce roof moisture from below

When to Call a Professional

If moss is more than half an inch thick, covers more than 25% of your roof, or your roof is steep or two-story, this is a professional job. The risk of damaging your roof (or yourself) isn't worth the savings.

HomeKeep's Approach

Our Complete and Premium plans include annual moss treatment at the optimal time. We use professional-grade zinc sulfate solutions, applied safely, with a follow-up brush-off three weeks later. Prevention strips are available as an add-on for homes in heavily shaded areas.