How To Clean Pavement From Algae?

Pavements serve as habitat for various types of organisms. A green film or powdery deposit is typical of algae on paving. Cleaning pavers becomes difficult when algae take shelter. Special cleaning methods have to be adopted to ensure that the existing algae are eliminated and new ones do not crop up again.

Pavements made of certain materials like Indian sandstone and limestone tend to have greater algal growth compared to others. Algae tend to grow and thrive in places where the weather is damp and pavements retain lot of moisture. The first step therefore is to keep the pavements clean and mop them dry at regular intervals.

An inferior variety of household bleach is ideal for cleaning pavers infested with algae. There are different kinds of bleach available in the market. Never choose the thick gelatinous bleach for cleaning pavers as it is very strong and might damage the appearance of the pavement.

Dilute the sodium hypochlorite solution (bleach) by mixing clean water and then pour it on to the pavement. Always keep a bucket of clean water ready to dilute the bleach if it happens to spill over to the adjacent lawn or other plants nearby.


Never use the thick jellylike bleach as it does not spread evenly and tends to stagnate at a particular place. As a result certain portions of the pavement get excessively bleached while the other portions remain unclean. This gives a very unseemly appearance.

It would also be better to avoid using bleach that has strength above eight percent and also that with lot of anionic surfactants. Cleaning pavers infested with algae has to be done two to three times for optimum results.

Stronger bleach has a greater cleaning effect but it is worthwhile to remember that a product with such potency might also affect the surrounding lawns, cultivated plants, and trees.

Algae float around in the air as spores and make home on any surface that has moisture. They settle down in the empty joints of pavements and thrive by absorbing minerals from the surface and water from the soil. The greenish discoloration that is seen on pavements is algae.

Algae seldom stay in isolation. They live as a colony. It is relatively easy to remove the small algal colonies while large colonies require more aggressive and frequent cleaning. In addition to bleach copper sulphate is also used to clean algae-infested pavements.

cleaning paving

Copper sulphate crystals are added to a prescribed quantity of clean water. This solution can be swiveled or sprayed on to the pavement. It is advisable to spread the solution evenly all over the pavement and not just over the place that is affected with algae.

Always wear protective gloves over the hands while handling either bleach or copper sulphate solution. The copper sulphate solution should be left to dry for about seven days. After a week the area can be cleaned by swiveling water with a bucket or using a hose pipe. It should later be cleaned using a stiff brush to remove any remnants left.

Tags: home cleaning, how to clean

One Response to How To Clean Pavement From Algae?

  1. Avatar for Deb McCutcheon Deb McCutcheon says:

    Is copper sulphate safe for limestone sills?

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