Common Types of Roof Stains

Common Types of Roof Stains

2nd June 2021

Common Types of Roof Stains

2nd June 2021

Getting stains on your roof is a nightmare for every house owner. Those black lines running down the roof just gives you the dreads. With every stain on the roof, it is the need of the hour to clean it is as quickly as you can. But before you get to cleaning the stains, you must identify the different types of stains that cover your roof. Taking a thorough diagnosis will help you to know the causes of these roof stains.


Algae is green in colour and is very destructive to the roof. If you do not get rid of it as soon as it appears, it will damage your entire roof. Usually, algae stains develop during the rainy season and in places where there is a lot of dampness and moisture the whole year-round. The algae spore lands on the roof because there is a lot of moisture on your roof. Algae can also make home in an area where there is a lot of humidity in your place.


Moss is a fungus that many homeowners prefer to keep on their roofs. They do it because, as the moss spreads to the entire roof, it makes the house look rustic with an earthy approach. But, like all fungus, letting moss spread onto your roof can cause damages. Sine moss retains moisture which can be problematic. If the moss spreads to the entire roof, then your entire roof will retain moisture. This moisture can create cracks and even bring down the whole roof.


Mould is a common fungus that is very destructive for the house. It is usually black but can also be green or brown. It has a foul smell that every homeowner recognizes. If you do not get rid of it quickly, it can cause health hazards like allergies, asthma or even depression. Mould usually thrives in houses and roofs made of wood where water trickles in small cracks or rotten wood.


Mildew is another type of fungus that is even more dangerous than mould, moss and algae. It is dangerous for the inhabitants and the house’s structures. It is usually grey but can also be black or pink. It causes similar health hazards like mould that may enter your airway and affect your lungs. It also spreads very fast, especially in humid and wet places. Usually, mildew affects your roof if you do not have a proper drainage system.


If your house has a metal or tin roof, rust can destroy your roof if your roof starts to change its colour into a reddish or brownish colour. Usually, your roof gets affected by rust through minor problems like a rusted nail that ultimately spreads through the whole roof.

Asphalt Bleed-through

If you have an asphalt shingle roof, you will notice black streaks on them. This indicates that your shingles are breaking down. You may need to call your local contractor to check the condition of your asphalt roof.


All stains are equally destructive to your roof, and we hope that you will get rid of them as quickly as you can. Knowing the stains on the roof will help you how to get properly rid of them.