Moss & Algae Removal in Petaluma, California

The North Bay is known for its trees, and the shade they cast grows moss on the roofs. The winter rain and the shade from the mature trees create the perfect conditions for the growth. Moss & algae removal in Petaluma protects the shingles from the moisture the growth traps.

Signs Your Petaluma Roof Has Moss or Algae

• Green or black patches on the shaded slopes — the moss is taking hold
• Black streaks running down the roof — the algae is feeding on the shingles
• Moss growing in the valleys and around the flashings — the growth is in the vulnerable spots
• Lifted or curled shingle edges — the moss pushed under the edges
• The roof stays damp after the rain — the growth is holding the moisture

Why Petaluma Roofs Get Moss and Algae

The North Bay has a wet winter season. The rain from November through March keeps the roofs damp, and the mature trees in the established neighborhoods shade the slopes.

The shaded slopes stay damp for days after the rain. The moisture feeds the moss and the algae. The algae eats the limestone filler in the shingles, and the moss holds the water against the surface.

How We Remove Moss and Algae in Petaluma

1. Inspect the roof — locate the growth and check the shingle condition
2. Treat the growth — apply a moss and algae treatment to the affected slopes
3. Soft wash the roof — a low-pressure rinse that removes the growth
4. Hand remove the heavy spots — scrape the moss from the valleys and the flashings
5. Protect the roof — apply a treatment that slows the regrowth

Moss & Algae Removal Costs in Petaluma

Service	Typical range	What’s included	Warranty
Light algae removal	$350 – $700	Soft wash, algae treatment	1 year
Moderate moss removal	$500 – $1,000	Treatment, soft wash, hand removal	1 year
Heavy moss removal	$800 – $1,500	Treatment, soft wash, hand removal, sealing	1 year
Zinc treatment add-on	$200 – $500	Ridge zinc strips or zinc spray	1 year

Preventing Moss and Algae in Petaluma

• Trim the tree branches over the roof — the shade feeds the growth
• Clean the roof every two to three years — the growth is easier to prevent than to remove
• Add zinc strips at the ridge — the zinc washes down and slows the algae
• Keep the valleys clear of debris — the trapped leaves hold the moisture

Expert tip: in Petaluma, the moss concentrates on the slopes that face the tree shade. Those shaded slopes are the ones we treat every year.

Serving Petaluma and Nearby Areas

We remove moss and algae across the North Bay — Petaluma, Santa Rosa, Novato, Rohnert Park, and the surrounding communities.

FAQ

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Start with a free roof inspection and moss removal estimate. Call us today for local crews.