Within a season
Heavy Moss on the Roof — Is It a Problem?
Most Lancashire roofs grow moss — our climate is perfect for it. Whether it actually matters depends on where it is and how deep it's grown.
What you're seeing
- Green/brown moss covering more than ~20% of the tile face
- Moss building up in the valley or against the gutter
- Tiles lifting at the edges where moss has wedged underneath
What it means
Moss itself doesn't damage the tile — but moss holds water against the tile and against fixings, and during freeze-thaw cycles that water cracks the surface. Moss in valleys and gutters is the bigger problem because it blocks drainage.
Do this now
- Don't power-wash — it strips the tile surface and forces water under the laps
- Clear visible moss from gutters and valleys (carefully) or call us in
- Keep an eye on it after heavy rain to check for blocked drainage
Professional fix
Soft-bristle scraping, biocide treatment, then valley and gutter clear-out. We don't pressure-wash domestic roofs as a rule.
Typical cost
Domestic moss treatment typically £350–£900 depending on roof size and access.