How to Clean Your Roof Stains

How to Clean Your Roof Stains

3rd June 2021

How to Clean Your Roof Stains

3rd June 2021

If you’re reading this article, then you must be wondering what those black stains on your roof are and how to remove them. 

Regardless of whatever types of roofing materials you use, it’s inevitable for your home roof to get stains eventually. The downside is that it not only reduces your home appearance but also shortens its lifespan.

However, the good news is that there are ways to clean and remove roof stains. Continue reading if all you want is to solve this problem.

What are those roof stains?

Before we dive further, we must understand what causes stains on your home roof. Though the stains on your roof appear like soot or dark mold, the stains are airborne algae.

These black algae generally thrive in humid and moist areas, where there’s less light. Besides, they feed on moisture and minerals inside the shingles. For this reason, black algae are significantly common in homes with asphalt roofing materials.

Are Stains on Your Roof Bad?

Although black stains don’t cause any severe damages immediately, it does come with some disadvantages. 

Firstly, roof stains significantly wreck the aesthetic appeal of your home. So if you’re planning to sell your house in the future or wow your guests, then you should consider removing them.

When left untreated for an extended period, roof stains can weaken the surface of the roof shingles. The reason is that algae increase the moisture retention rate, thereby letting lichen and mold flourish. It can further reduce the durability of your roof in the long run.

How to Clean Roof Stains:

If you’re looking for tips and ways to clean your roof stains, then consider these guides:


When cleaning your roof stains, you cannot compromise your safety. Remember, roof cleaning can become very dangerous without safety measures. 

Some safety precautions include wearing non-slippery shoes, using protective gloves and goggles, and using safety ropes when required. Additionally, we recommend undertaking safety measures for the nearby plants while using chemicals. 

However, the best way to ensure safety for cleaning roofs will be to hire a professional roof cleaning service.

Clean during a cloudy day:

It will be best to clean your roof stains during a cloudy day. In this way, you can soak deep the dark stains without letting the roof cleaning solution evaporate too quickly.

Always flash the gutters:

This step will allow you to clean your roof stains without causing any blockage. So we recommend removing all the leaves, dirt, and debris from the gutters.

Avoid high-pressure washing systems:

Using a power washing system can significantly do more harm to your roof shingles. Besides, it can damage the roof protective coating, thereby reducing durability.

Cleaning process:

A basic formula for cleaning your roof stains calls for 0.25 cups of trisodium phosphate, one gallon of water, and one quart of sodium hypochlorite. With the help of a sprayer or cleaner, thoroughly soak the roof shingles and leave it for about 15 minutes. Finally, you can rinse it off with a hose.

Prevent re-growth:

It’s worth noting that cleaning doesn’t remove the dark algae permanently. However, you can take extra measures to prevent its re-growth. One way is by install copper or zinc-coated strips on the rooftop. Another better option to prevent the re-growth of black stains is by using algae-resistant shingles.


To sum up, the above-listed points are some essential guides that can help you clean your roof stains. However, if you’re not confident about carrying out this cleaning process, we recommend hiring an expert. Remember, cleaning your roof stains isn’t an easy task.