Does Lichen Cause Damage to a Roof?

Hobart Gutter Cleaning

The short answer to this question is yes.

What is Lichen?

Algae and fungus in close quarters to each other form lichen. Rooves, footpaths, driveways, etc are the substrates on which it can grow. The fungus is fed by the algae as the nutrient and this forms the lichen. Wind carries debris, trees can drop debris or any other type of organic matter that reaches your roof can have the elements of fungus and algae in it. Sunlight, moisture, oxygen and nutrients are needed to form lichen. If just one spore of algae reaches the roof, it can cover the entire section over time, as algae is a fast-reproducing organism.

Lichen holds in moisture and will deteriorate the roofing material at a much faster rate. The roof becomes damaged and water ingress could become an issue. In our Hobart climate, winter can become a problem to a lichen covered roof. The moisture freezes the lichen and can cause roofing material to twist, bend or even break.

Lichen can take a long time to present problems on a roof but once lichen gets a hold, it has the strongest grip. The grip becomes stronger if left to grow unchecked. Lichen lodges itself in the layers of your roofing material and can leave holes when it is eventually treated. The lichen dies off taking the layered material with it.

There are two ways to remove lichen:

  1. Pressure washing the roof. It is cleaned immediately of the lichen but the roots and spores are left in the cracks and crevices of the roof. The lichen grows back and it is usually thicker. Therefore, regular pressure cleaning is required. The problem with this, is that the pressure cleaner removes the protective coating of the roofs each time and over time will remove it completely, leaving the roof with no protection.
  2. Treatment of the Lichen. A spray can be applied to the lichen. It usually takes 12 months to die off. Some thicker stubborn areas may need a further spot treatment. Rain events activate the treatment each time and the slow process kills the lichen, roots and spores. It may be that the occasional spot treatment will be required as maintenance but the bonus to this is that it does not deteriorate the roof like constant pressure cleaning.
Hobart Gutter Cleaning

The upshot is that preventative maintenance is far more cost effective and less damaging than waiting for something to go wrong before fixing it.

We use the product called Wet and Forget to treat Lichen. It would be a good idea to call in the professionals when applying this to your roof. Safety should come first and the application of any treatment will wet the roof and make it slippery. We are trained at heights and have all the right gear to apply the treatment in a safe manor.

Get ahead of the problem, prevention could be less costly than repairing damage.

If you’d like our professional team to clean the lichen from your roof safely, you can Request a Quote here.

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