Over time your roof can become dirty from bad weather, build up of debris and moss.  If you look after your roof and clean it regularly, you can avoid costly damage and degrading.  If you feel confident, you can do this yourself, if not, it’s best to call in the experts.

Firstly have a good look at the roof and assess the condition of the roof and the areas that need to be cleaned.  Look for debris, moss, and black staining.  Notice any areas of broken tiles where it may be unsafe to walk.


Before you attempt to access the roof, don’t forget to take appropriate safety precautions;

  1. Use the right ladder length and extend it beyond the guttering, this will allow you to get a solid footing onto the roof.


  1. Wear protective clothing such as hard wearing boots, and full length trousers.  If you’re spraying, safety goggles may be required too.


  1. Where appropriate, use a harness.


  1. Where possible, work with a mate so they can hold the ladder and keep an eye on you.


Pressure Washing

If you choose to pressure wash your roof proceed with caution, the jets on these can be very powerful and can easily damage tiles.  It’s much better to clean a roof by hand using the below methods.

Removing Debris

Debris from nature such as leaves and twigs can be removed from the roof using a brush or blower.  If you have a safe way of accessing the roof and appropriate protection, you can also remove this by hand.


Removing Moss

Moss occurs particularly where there are shady areas on the roof.  Moss shortens the life of your roof by retaining moisture which over time will transfer to the tiles which can then rot away.


Start by lightly sweeping the moss from the roof.


Applying a zinc strip to your roof can stop moss from regrowing in future - this is applied just beneath the ridge and is tacked into place.  As rain water passes over the zinc strip, the particles are carried on the water down the roof and this kills any build up of moss.

You can clean off more stubborn moss with a trowel and wire brush


While you’re on the roof it’s worth checking for and replacing broken tiles.



If your shingles are showing signs of black staining, this may be a signal that your roof is suffering with a build up of algae.  Algae feeds of asphalt shingles made with limestone.  Over time the algae weakens the tiles making them more susceptible to heat absorption.


Algae can be removed with a solution of non chlorinated bleach and water which can be lightly sprayed onto the roof (don’t use a pressure washer) and then brushed off.  Rinse the roof with water afterwards.


Tip - protect surrounding bushes and plants by watering before and after as the bleach can kill them.  Watering will dilute any bleach that gets on to them.