L & N Roofing | Roofing Services in Lake Oswego, OR 97035

In our damp climate, moss doesn't just look unsightly—it's actively damaging. Moss roots can work under shingles, lifting them and breaking the waterproof seal. More critically, moss holds moisture against your roof deck 24/7, which can lead to wood rot, mold in your attic, and eventually leaks. Professional removal and treatment prevent this cycle of damage, protecting your home's structure.

We strongly advise against high-pressure washing, as it can blast away the protective granules on your asphalt shingles, shortening their life. The professional method is a low-pressure soft wash with specially formulated, eco-friendly cleaners that kill the algae at the root and allow the stains to rinse away gently. This is effective, safe for your roof and landscaping, and includes a treatment to help prevent regrowth.

While nothing is 100% permanent in our environment, yes, we apply preventative treatments. After a thorough cleaning, we typically install zinc or copper strips near the roof's peak. When it rains, tiny amounts of these metals wash down the roof, creating an environment that inhibits moss and algae growth for years. We also recommend keeping nearby trees trimmed to increase sun exposure and airflow, which naturally discourages growth.