How do you remove efflorescence from concrete pavers is a frequently asked question here at Al Manaratain. But, before we get into the details of concrete efflorescence – we thought we should outline exactly what efflorescence is first… Efflorescence is a crystalline or powdery deposit of salts often visible on the surface of concrete or natural stone surfaces. It occurs when water present in the concrete or on the concrete or from the paver under laying surfaces evaporates and leaves behind salt deposits on the masonry surface. Efflorescence is formed by a normal chemical reaction between cement and water which causes calcium hydroxide (lime) to migrate through damp concrete to the paving surface and then react with carbon dioxide in the atmosphere resulting in a deposit of calcium carbonate crystals. Efflorescence is very unpredictable in its occurrence and there are multiple reasons causing it. But it is more prevalent in winter when concrete becomes wet and dries more slowly.
Most products that are laid on the ground like interlock paving, hydraulic press pavers and kerbs are affected by Efflorescence. But it can appear on brick walls or concrete block masonry walls as well if they are in contact with moisture.
How Do You Remove Efflorescence From Concrete Pavers?
Now we know exactly what efflorescence is, we can now go ahead and answer the question: how do you remove efflorescence from concrete pavers?
Treating Early Stages Of Efflorescence:
- If you are tackling early efflorescence on pavers you may be able to simply brush it away using a large push-broom or stiff-handled brush. This method keeps the salts from being washed back into the pavers, so it should be the first thing you try. This is to avoid the efflorescence crystallizing further and making it even harder to remove. This may take some elbow grease, however, if you are persistent, this will certainly do the job.
- If the first step fails to remove efflorescence, you should then apply a small amount of water, this can help to loosen the salt. However, water shouldn’t be your first choice, because you could rinse some of the salts back into the brick, which could result in the efflorescence returning.
Treating Stubborn Efflorescence:
If the efflorescence you are treating has already crystallized, you will need to further steps to treat the affected area.
- You should start by sweeping the area with a hard dry brush, to start removing the loose efflorescence. This will help ensure that you don’t wash any of the salts back into the pores in your pavers.
- Next you should rinse the pavers with 6% vinegar. Vinegar is extremely effective against removing efflorescence from any surface, whether it be interlocking pavers, concrete pavers or bricks. You also do not have to worry about rinsing dangerous acids into the soil around your pavers. Once you have poured vinegar that is 6% acid over the pavers, scrub them with a brush, then rinse it away with a water hose.
- If you have not fully achieved the results you would like after taking the steps above, the final option is to use an efflorescence cleaner. And repeat the same techniques as above (scrubbing with a hard and ensuring that all the crystallized efflorescence has been removed.) You should then follow the steps that have been outlined on your bottle of efflorescence cleaner, this is really important as they contain harmful chemicals. For this reason- we would always recommend wearing gloves and goggles to protect yourself.
Please remember that when it comes to treating areas around your home that are suffering from efflorescence, you should always start with the lowest impact measures first. If you head straight into using an efflorescence cleaner before trying to remove all of the excess efflorescence first, this can often make it worse and even harder to remove as the salts are washed back into the affected area.