HOW TO REMOVE STAINS OF CLAY PAVED SURFACES?

how to clean clay surface

Clay paving provides a durable, hard-wearing surface, but like any surfacing material, it can stain from time to time due to general trafficking and contamination from other sources.


Due to the nature of the construction, there may also be some vegetation growing on the floors themselves, in joints, or in shaded areas or areas subjected to prolonged moisture.

As for any other surfacing material, regular maintenance and good cleaning practices will enhance the overall appearance of the floor.

Initial maintenance – flexibly laid earthen pavers

During the pavement’s early life, the joints between the pavers will be relatively porous. The ingress of water will strengthen the joint sand and it is important that the joints are regularly filled with sand to replace the aggregated sand by rainwater.

Joints will soon become semi-impermeable due to their tendency to seal. Until this happens, the floor should only be brushed by hand.

Mechanical sweepers, and especially sweepers with high suction forces, should not be used. If they are used, there is a real risk of adding sand from between the pavers.

There are many water miscible fluids that can help stabilize the sand that fills the joint. These suctions can help reduce sand removal by the cleaner, and at the same time, help prevent water ingress during the early life of the pavement.

Consulting with the paver manufacturer is essential before applying any form of surface treatment.

1. Common Dirt and Detritus

Regular brushing is recommended to remove common dirt and grime. If detritus masks the color of the material it can be re-established by scrubbing with warm soapy water. This can be done by hand or using an industrial cleaner. Make sure all detergent has been thoroughly washed off the surface when cleaning is complete and that the resulting runoff is carefully diverted to either drainage points or containers where it can be safely disposed of.

If a hose is used, care must be taken to avoid removing the joint material (sand or mortar).

2. Mosses, Lichens and Algae

Mosses, lichens, and algae should not grow on soil pavers unless the area is heavily shady, under trees, or placed close enough to fall. If such growth occurs and is considered undesirable the area should be treated with a proprietary moss killer used according to the manufacturer’s instructions.

Such products take a few days to take effect and work best when applied during dry weather. Any thick growth should be removed first and chemically treated thoroughly brushed off.

Some treatments leave a residue to discourage the re-growth of moss and algae, but this will only be of limited value if the flooring remains moist and in shade.

3. Rust Stains

First of all, action should be taken to eliminate the sources of staining.

The surface should be moistened to remove the rust stain and then the affected area should be treated with a solution of 5-10% hydrochloric acid. Prior to cleaning, provision should be made for the collection and disposal of waste chemical material in accordance with legislative requirements.

Buff clay pavers should not be treated with acids without first discussing the stain with the paver manufacturers.

4. Oil Stains

Oil does not penetrate mud pavers easily, but if oil is spilled on the pavers, the leak should be removed immediately with an absorbent material, such as paper towels. Oil should not be wiped off; Otherwise it will spread contamination on the surface of the paver.

Steam cleaning can be used on clay pavers to remove such stains, but an emulsifying de-greaser should be used if this is unsuccessful. Brush with plenty of water for safe disposal. An alternative cleaning method is to brush the area with a strong detergent and warm water. It will not affect the color of the clay floor.

5. Bitumen Stain

Bitumen does not easily penetrate the earthen floor. The best way to remove it is to leave the bitumen to cool.

A paint scraper or similar mechanical tool can often remove it. If it is particularly resistant, it may require the use of ice to make the bitumen even more brittle, before scraping it off the floor.

Any residue should be removed with scouring powder and finally the entire area should be washed with clean water. There are some proprietary cleaning agents available to remove bitumen, but these should be tested on an inconspicuous area of ​​the floor first.

6. Graffiti and Paint Stains

Both paint and graffiti are difficult to remove. Freshly wet paint should be soaked with an absorbent material without wiping off the paint, as this will spread the stain. It should then be treated with a suitable solvent, such as white spirit, and then the area should be washed with a de-greasing agent, taking care in disposing of the runoff material.

7. Smoke, Fire and Tobacco Stains

These stains can usually be removed by scrubbing with warm soapy water. Where stains persist, a solution of scouring powder or household bleach has been found to be successful.

8. Drink Stain

These can usually be removed by scrubbing the stain with warm soapy water. If the stain persists, apply a bleach solution and then wash the area with clean water, taking care to remove it safely with running water.

9. Chewing Gum

Chewing gum is one of the most difficult substances to remove from any surface material.

Newly discarded glue can be removed using a scraper, but hardened glue can be removed simply by freezing the gum and chiseling it off the surface of the floor, or alternatively, using a hot water/steam cleaner.

There are several contract cleaning companies that specialize in this type of cleaning, and it is advisable to contact them directly for more information.

10. Scratches from vehicle tires

These can usually be removed by steam cleaning, or by scrubbing the area with warm water and a strong household detergent solution.

11. Flowers on Clay Pavers

Any soluble salts that appear on the surface of the paver should be allowed to naturally weather out, as experience shows that such weathering will occur quite rapidly. These salts are not harmful to clay floors. Chemical treatment should not be used,

Some light colored pavers are constructed from fireclay and in extreme cases may suffer from metallic salt staining. Vanadium efflorescence takes the form of a yellow/green stain, and orange/brown deposits may result from iron or manganese compounds.


These stains should be allowed to go away naturally, but if they persist, contact the paver manufacturer.

12. Cement Staining

Remove large deposits with wooden tools to avoid damaging the surface of the paver.

After pre-wetting the area, treat the mortar residue by careful application of a dilute hydrochloric acid solution or a proprietary cleaning solution. The use of acid breaks down the components of cement but is not harmful to clay pavers.

with all cleaning procedures; A rinsing operation should be performed immediately after application, and care should be taken to safely dispose of the runoff solutions.

If the above method is not successful with colored mortar, expert advice from a colored mortar supplier should be sought.

On the rare occasions when a vanadium upfluorescence is present, a hydrochloric acid based cleaner must do the trick. No Come into contact with the inflorescences, otherwise a dark stain will form that will settle on the surface.

13. Lime Staining

Lime staining should not occur on flexibly laid earthen pavers. However, contamination from an external source, such as concrete street furniture or concrete units discharging running water over clay pavers, is a possibility.

Lime staining eventually becomes insoluble and appears as a white stain. In the unlikely event of such staining, clay pavers should be moistened and then the surface treated with a hydrochloric acid solution of 5-10% concentration.

with all cleaning procedures; A rinsing operation should be performed immediately after application, and care should be taken to safely dispose of the runoff solutions.

14. Iron Staining

It can appear in many forms from orange to dark brown and can affect the surface of the paver and tarnish any mortar joint.

The staining of the iron will reduce over time and should be left to go away naturally. Although in severe cases, the following techniques have been found to be successful in removing the stain.

Removal from the face of the mortar joint is best achieved by scraping or rubbing with a round file or carborundum slip. Where overall cleaning is required, the following chemical treatments have been found to be effective:

Brush on a solution of 5-10% hydrochloric acid. It is often satisfactory on fresh stains. For this, proprietary brick or patio cleaners can be effective, but, as with all treatments, a small test area should be done first. For more persistent stains, repeated applications may be necessary.

15. Manganese Staining

It is similar to iron staining, but is usually dark brown or black in color, and the treatment is essentially the same. If chemical treatment is required the following methods have been used:

On fresh stains, brush on a 5-10% hydrochloric acid solution or a proprietary brick or paver cleaner.

In more severe cases a combined solution of hydrochloric acid (10%) and hydrogen peroxide (10%) may be effective or, alternatively, paint the stain with an oxalic acid solution (120 g/l).

mechanical cleaning

The following recommendations pertain to vehicles and related equipment and their use:

1) The purpose of the equipment must be designed to clean the particular area. If there is any doubt, the vehicle manufacturer should be consulted.


2) Tires should be inflated according to manufacturer’s recommendations to ensure maximum weight distribution.

3) Polypropylene, not wire, brush should be used.

4) Sweeping brush pressure should be set to the minimum required for the particular task, i.e. regularly swept surfaces will require a lower setting than those frequently swept or covered with heavy deposits.

5) When sweeping, engine revolutions should be set to the minimum required to maintain vacuum (suction) pressure.

6) Operators, including Reliefs, should be trained on tire and brush pressure, as well as vehicle manufacturer’s recommendations, to be checked regularly.

7) Operators should be advised that, when the equipment is stationary or left unattended, the suction, brush rotation and water jetting equipment should be turned off to avoid the risk of damage to the area under the stationary equipment.

8) In new or re-laid areas, agreement should be made with the local highway authority to settle the pavement and seal the joints before manual cleaning.

9) When water jetting equipment is used to wash such areas, jet or hand held lances using a suitable detergent solution to the surface at an angle not exceeding 30o and diagonal (ie not parallel to the joints) should be directed.

10) After cleaning the area should be inspected to ensure that the joints are filled with sand if necessary.


Er. Mukesh Kumar

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Er. Mukesh Kumar is Editor in Chief and Co-Funder at ProCivilEngineer.com Civil Engineering Website. Mukesh Kumar is a Bachelor in Civil Engineering From MIT. He has work experience in Highway Construction, Bridge Construction, Railway Steel Girder work, Under box culvert construction, Retaining wall construction. He was a lecturer in a Engineering college for more than 6 years.