Roof Cleaning in London — What It Involves
Professional roof cleaning removes moss, algae and lichen from tile and slate roofs, usually using soft washing and biocide treatments rather than high-pressure jetting, which can crack tiles and force water underneath them. First Rate Jet Wash focuses on ground-level surfaces — driveways, patios, block paving and decking — and doesn't currently offer roof cleaning directly. Get in touch and we'll point you toward a trusted local roof cleaning specialist.
Why Roofs Need Professional Cleaning
Moss retains water against the tile surface, which freezes and expands in winter — cracking and loosening tiles over time. Moss debris also washes into gutters, causing blockages and overflow. Algae (often Gloeocapsa magma) causes permanent black streaking, while lichen embeds into the tile surface and won't wash away in the rain. Left unchecked, the weight of heavy moss buildup can even stress the roof structure.
Roof Types That Commonly Need Cleaning
Concrete Tiles
The most common UK roof type. Tolerates soft washing well but is prone to heavy moss buildup.
Clay Tiles
Common on period properties. More fragile — high-pressure washing should be avoided; soft washing only.
Slate
Naturally resistant, but lichen and moss still accumulate over time. Requires a gentle technique.
Flat Roofs
Pooling water accelerates algae growth. Needs specialist, drainage-aware cleaning.
How Professional Roof Cleaning Works
1. Survey
Roof assessment from ground level to identify growth, access route and any repair needs.
2. Safe Access
Scaffolding, cherry picker or roof ladder, depending on the property and a proper risk assessment.
3. Manual Moss Removal
Bulk moss scraped and brushed off before any chemical treatment.
4. Biocide Application
Professional-grade soft wash treatment kills remaining growth at the root.
5. Low-Pressure Rinse
Where needed — never high-pressure.
6. Gutter Clearing
Moss debris cleared from gutters after the roof clean.
Biocide continues working for several weeks after application — full results are typically visible at 4–8 weeks.
Why High-Pressure Washing Isn't Used on Roofs
High-pressure washing can crack and dislodge tiles, force water under tiles into the roof felt and structure, strip protective coatings, and void some tile manufacturer warranties. This is why reputable roof cleaners use soft washing and biocide treatments instead.
Pricing
Roof cleaning costs vary by property size, roof type and access requirements — see our roof cleaning cost guide for typical ranges. As this isn't a service First Rate Jet Wash currently delivers directly, get in touch and we'll point you toward a trusted local specialist for an accurate quote.
Frequently Asked Questions
Usually yes — it prevents costly tile damage from trapped moisture, extends roof life, and prevents gutters from blocking with moss debris.
A professional biocide treatment typically prevents regrowth of moss and algae for 2–5 years, depending on the roof's aspect and surrounding trees.
It depends on the property. A specialist will assess access first and use the safest suitable method, often a cherry picker or roof ladder rather than full scaffolding.
Spring or autumn — mild weather and safer working conditions, and treatment has time to work before winter frost or summer growth. See our seasonal timing guide.
Often yes, using long-reach lance systems and cherry pickers depending on the roof layout and access.
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Considering Roof Cleaning?
Get in touch and we'll point you toward a trusted local specialist.