Your roof says a lot about your house. It’s often the first thing people notice about your home. You want to take pride in this important exterior feature, but you’ve noticed some unsightly dark streaks appearing all over your shingles or slates. Where did the contaminant come from? Is it mould, soot or dirt?

Those black streaks are actually algae. In humid climates like that of Adelaide, algae starts to form because of the moisture on  your roof. And if the build-up looks green and fuzzy, you probably have a moss problem. Both moss and algae possess similar properties and require the same kind of removal.

Algae and moss generally won’t harm your home directly, but they also won’t go away on their own. Keep reading to find out more about algae removal and preventing future growth.

Removing Algae

Different types of roofing will affect the cleaning process and make algae removal more difficult. Delicate shingles, for example, will require a more delicate wash. Otherwise you might remove your roof along with your algae problem. Because the process requires knowledge and expertise with different roofing materials, call a professional to come fix the problem. Additionally, when you navigate a wet roof without a lot of experience, the activity might result in a dangerous fall. Thousands of Australians end up in the hospital each year due to falls during household maintenance. Even a fall from a height of a couple meters can cause serious injuries.

The roof repairman will use some type of chemical to eliminate the growth. By creating an uncomfortable pH level for the algae, the roof technician can clean off the growth more easily. These chemicals can either have acidic or basic properties, depending on what will work best for your roof. Then gentle scrubbing will clean up your home without harming the roofing tiles.

If you have a rainwater collection system, tell the roofing professional before he or she starts cleaning. That way you can make sure the chemicals don’t contaminate your rainwater tanks.

Keeping Your Roof Free of Algae

A good cleaning should keep algae away for a while. But eventually the algae will return, and your impressive, spotless roof will require cleaning all over again. If you want to prevent the algae from growing back at all, you should consider installing copper flashing.

When rainwater washes over exposed copper, minute traces of copper sulphate will wash over your roof. Copper sulphate is a known fungicide, and algae does not like to grow anywhere near it. In fact, algae may cover some rooftops completely except for the area directly below a chimney with copper flashing.

To recreate this effect, a roofing professional can install copper flashing across your roof. Thin strips of low-profile copper plating will spread out strategically across your shingles. Then, whenever it rains, your roofing tiles will receive a copper sulphate wash, clearing out any algae or moss.

Starting Over

If your roof has become completely overrun with algae or moss, and if you think about replacing your roof for a newer design sometime in the future, you might want to consider a roof replacement now. You don’t want to put the time and money into cleaning up your roof only to switch it out a few years later.

Once you have a new rooftop installed, keep an eye on it and check for algae often. You can clean and control algae much easier when it first starts to grow.

After you apply these techniques, your algae-covered roof will look like new again. And if you suspect an algae or moss problem, contact a roofing professional. He or she will examine your roof and let you know your best options.