If you've been putting off your roof clean because of something you heard, this is for you. These are the five myths we hear most often from homeowners across Kent, Sussex, and Surrey, and what's actually true.
Myth 1: 'My roof looks fine, so it doesn't need cleaning'
Moss, algae, and lichen don't always make themselves obvious from ground level, especially in the early stages. By the time a roof looks visibly green or black from the kerb, the growth has typically been established for years. More importantly, the damage happens beneath the surface. Moss holds moisture against tiles, causing freeze-thaw cycles in winter that crack and lift them. Lichen bonds to the surface and physically breaks down the tile material over time. Waiting until the problem is visible from the street means waiting until it's already expensive.
Myth 2: 'Pressure washing will crack or break my tiles'
This one has some basis in truth, and high-pressure washing applied incorrectly to fragile or aged tiles can cause damage. The key word is incorrectly. Professional roof cleaners assess the tile type and condition before choosing an approach. For concrete and clay tiles in reasonable condition, professional-grade pressure washing is entirely safe. For more delicate surfaces, a soft wash approach (lower pressure, longer biocide dwell time) achieves the same result without the risk. Any cleaning company telling you it's pressure wash or nothing isn't giving you the full picture.
Myth 3: 'I'll just do it myself with a hose or a brush'
The risk here is twofold. First, working on a pitched roof without the right equipment and training carries a serious fall risk. It's not a job for a ladder and good intentions. Second, the tools available to most homeowners won't achieve meaningful results. A garden hose won't shift established moss, and scrubbing the surface by hand simply detaches the visible growth without killing the root system, meaning it returns within weeks. Professional cleaning isn't just about the equipment. It's the biocide treatment that determines how long the result lasts.
Myth 4: 'Roof cleaning is cosmetic. It's not worth the money'
This is the most expensive myth to believe. A roof that's allowed to accumulate biological growth will cost significantly more to repair or replace than it costs to clean. Moss and lichen cause tile deterioration. Sustained moisture retention accelerates the degradation of the bedding mortar around ridge tiles and verges. Blocked valleys (often full of compacted moss) cause water to back up under tiles during heavy rain. The cleaning cost is small relative to a re-bedding job, let alone a partial re-roof.
Myth 5: 'I'll sort it when it starts leaking'
At that point, sorting it means repairs as well as cleaning. Water ingress is a downstream symptom of surface and structural deterioration that's been building for years. The leak is the last thing to appear, not the first warning sign. Regular maintenance, catching growth early and treating it, is always cheaper than reactive repair. Most of the customers we work with in Maidstone, Tunbridge Wells, and across the South East come to us when they've finally had enough, and nearly all of them say the same thing: they wish they'd done it sooner.
If your roof is showing signs of moss or lichen, see our roof cleaning service. Soft wash, fixed price, covering Kent, Sussex and Surrey.