Moss on a roof is not just unsightly — it is a real danger. It roots into the tiles, making them porous and retaining water. In winter, that water freezes and cracks the tiles from within. Over a few years, a moss-covered roof ages twice as fast as a clean one. The north face, in the shade, is always affected first. A good cleaning followed by an anti-moss treatment extends the life of your roof covering by 10 to 20 years. Our method: no high pressure (it damages tiles), but a professional product that destroys moss down to the root, followed by a gentle rinse. Protection guaranteed 8 to 10 years.
Roof cleaning in Clermont-Ferrand costs between €15 and €25/m² depending on the roof condition and technique used. For a standard house (100 m²), expect €1,500 to €2,500 all-in. TOIT DES DÔMES uses a gentle, low-pressure method that preserves the tiles.
Clear and transparent guidance, from your first call to project completion.
Contact us to describe the state of your roof: visible moss, black stains, age of the covering. We schedule a free visit to assess the surface to treat, tile type, and level of soiling. This assessment determines the most suitable method and products. If you wish, we produce a detailed quote.
Before any work begins, we protect your walls, plants, and surroundings. Gutters are checked to ensure good drainage of rinse water. We install our safety equipment (harnesses, lifelines) in line with regulations to work safely.
We apply our professional cleaning product that dissolves moss, lichen, and algae without attacking the material. Unlike high pressure which strips the protective layer of tiles, our gentle method preserves their integrity and lifespan. Rinsing is done at controlled, uniform low pressure.
Once the roof is clean and dry, we apply a professional waterproofing treatment that penetrates the material and creates a lasting barrier against water and moss regrowth. Protection duration: 8 to 10 years. We carry out a full visual check and hand you an intervention report.
Moss is not just a visual annoyance. When it takes hold on your roof, its roots penetrate the micro-pores of tiles and create micro-cracks. Water seeps in, and during winter frost — frequent in Auvergne — it expands the cracks. Year after year, tiles become increasingly fragile and porous. It is a slow but irreversible process if left untreated.
Lichen produces acids that chemically attack the tile surface. Black algae (Gloeocapsa magma) create unsightly streaks and retain moisture permanently. On an infested roof, constant humidity also encourages fungal growth in the framework beneath. Acting early avoids far more costly repairs down the line.
Many homeowners think high-pressure washing is the most effective solution. This is a mistake. A high-pressure washer (Kärcher type, 100-200 bar) strips the protective surface layer of tiles — known as the slip glaze or patina. Result: the tiles absorb more water after cleaning than before, and moss returns faster.
Our gentle method works differently. We apply a professional anti-moss product that acts in depth for several hours, destroying moss and lichen down to the root. Rinsing is done at low pressure (20-40 bar maximum), enough to remove debris without damaging the surface. The result is more lasting and preserves the longevity of your roof covering. This is the method recommended by tile manufacturers.
Puy-de-Dôme (63) combines several factors that promote moss and lichen growth. Atlantic moisture carried by westerly winds meets the volcanic relief, creating frequent rainfall. Winters are long and temperatures often hover around zero, multiplying freeze-thaw cycles. The average altitude of the area (400 to 600 m) accentuates these effects.
In practice, Auvergne roofs grow moss faster than in drier or warmer regions. A north-facing roof shaded by trees can be completely colonised within 5 to 7 years. That is why we recommend cleaning every 8 to 10 years, and a full visual inspection every 2-3 years to anticipate problems.
The best time to clean your roof is in spring (March to May) or early autumn (September-October). These periods offer moderate temperatures — not cold enough to affect product performance, not hot enough to cause rapid evaporation. Avoid frost periods and plan for 24 to 48 hours without rain after the waterproofing treatment.
If you notice heavy moss growth, do not wait for the 'perfect' moment. It is better to act in summer during dry weather than to let the situation worsen for a year. Our team adapts its methods and products to current conditions to guarantee optimal results in any season.
Each service includes the following deliverables.
Every project is unique. We provide a free personalised estimate.
From €15/m²
Sliding scale by area. Cleaning + waterproofing combined: free on-site estimate.
Answers to your most common questions.
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