Garden Waste or Hazardous Waste?

1. Should the moss be treated as Asbestos Contaminated?

The short answer: Generally, yes. Moss doesn't just sit on top of the sheet; it sends "roots" (rhizoids) into the surface of the asbestos cement. As the moss grows and expands, it physically prys apart the top layer of the cement matrix. When the moss is pulled away—or falls off naturally—it often takes tiny asbestos fibres with it.

Therefore, any moss removed from an asbestos roof should be treated as Asbestos Contaminated Waste.

2. Can you put it in the garden waste bin?

Absolutely not. Disposing of contaminated moss in a standard garden waste bin or a home compost pile risks spreading friable asbestos fibres into the environment. Once the moss dries out, those trapped fibres can become airborne.

The Verdict

If your roof is turning green, don't ignore it—but don't treat it like a standard gardening chore either. Pressure washing is a strict "no-go" as it blasts fibres into the air, and scraping it dry is equally hazardous.

The safest approach? Consult a specialist who can apply an asbestos-safe biocide to kill the moss without disturbing the fibres, ensuring your roof stays light, and your lungs stay clear.