Cape Town roofs take a beating that roofs in drier parts of the country never see. Between the damp shade off Table Mountain, wet winters that grow moss and lichen, southeaster-driven grime and salt air near the coast, a roof here can go from clean to green in a couple of seasons. This is a practical, local guide to what your roof faces, how it should be cleaned, and when to get it done.
What Cape Town's climate does to your roof
Our Mediterranean climate is the whole story. Wet winters keep roofs damp for weeks at a time, and anything sitting in shade — the southern slope, or under a big oak or milkwood — barely dries out. That damp is exactly what moss, algae and lichen need to take hold, and once they do they trap even more moisture against the surface.
The southeaster adds its own layer, driving fine dust and grit across everything, while homes in Table View, Bloubergstrand, Muizenberg and the rest of the coastal strip get a steady dose of salt air on top. The result is the streaky green-and-black staining you see on so many roofs by late winter. It is not just cosmetic — left alone, that growth shortens the life of your roof. We cover the full picture in why roof cleaning matters.
Common Cape Town roof types (and how they're cleaned)
The right method depends entirely on what you're standing on. A few roof types dominate here:
- Concrete and clay tile: The most common pitched roof in the suburbs. Tough, but the surface is porous, so moss roots itself in and staining sinks in. Cleans up well, though older tiles chip if you get the pressure wrong.
- IBR and corrugated metal: Popular on newer homes, extensions and outbuildings. The coating scratches and the seams don't love a hard blast, so these are better suited to a gentler wash.
- Everite and asbestos-cement sheeting: Still on plenty of older Cape Town homes. This is the one to be careful with — high pressure on asbestos-cement can release fibres and is genuinely unsafe. It should only ever be soft washed, never blasted.
Soft washing vs high pressure
There's a stubborn myth that a roof just needs a bigger pressure washer. On most roofs the opposite is true. High pressure can crack tiles, strip the protective coating off metal, force water up under overlaps and blow out the bedding on your ridge caps — and it only knocks the moss off the surface, so it grows straight back.
Soft washing is the method that suits Cape Town roofs. A low-pressure spray carries a cleaning solution that kills the moss, algae and lichen at the root, then it's rinsed gently away. It keeps working for weeks after, so the roof stays clean far longer. High pressure has its place on hardy concrete tile that's caked in dirt, but even then it's a controlled, low-angle technique — not a full-power blast. When in doubt, softer is safer.
A note on doing it yourself
If you've got a low, flat, single-storey roof and a head for heights, clearing loose leaves and debris is fair game — especially before winter, and while you're at it check the gutters that the roof drains into. But actual roof cleaning is wet, slippery work at height, often on a pitch, sometimes over asbestos-cement. That's where most people are better off calling in a pro rather than risking a fall or a cracked roof.
Timing: clean before the winter rains
The best window is autumn, roughly March to May, before the Cape winter sets in. Go into the wet season with a clean roof and there's nothing for the moss to feed on, so it stays clear through the worst of the damp. Leave it and you spend all winter watching the green spread, then clean it in spring after the damage is done. For most homes here, a soft wash every couple of years keeps things under control — sooner if you're in deep shade or right on the coast.
Frequently asked questions
Will pressure washing damage my roof tiles?
It can. Full-strength high pressure cracks older concrete and clay tiles, strips coatings off metal, and forces water under the overlaps. That's why we soft wash most Cape Town roofs — low pressure plus a cleaning solution that kills the moss at the root without harming the tiles.
Can you clean an Everite or asbestos-cement roof?
Yes, but only by soft washing. High pressure on asbestos-cement sheeting can release harmful fibres and is unsafe, so those roofs must never be blasted. A gentle low-pressure treatment cleans them safely.
When is the best time to clean my roof in Cape Town?
Autumn, before the winter rains arrive. Going into the wet season with a clean roof stops moss and algae getting a foothold, so it stays clear through winter instead of spreading in the damp.
How often should a Cape Town roof be cleaned?
For most homes, a soft wash every two years or so keeps moss and staining in check. If your roof sits in shade off the mountain or you're near the coast with constant salt air, you may need it a bit more often.
Want it done right? See our roof cleaning service, get a free quote, or call us on 079 616 7761.