We were called to this property in Kingston Southwest London KT2 to perform a Patio cleaning service and blackspot removal service on their Indian sandstone patio.

On arrival the patio appeared to be very dull in colour, it was infested with black spots and was definitely in need of a good clean After having a better inspection of the patio and discussion about our patio cleaning techniques with the owner.

It was decided that we would perform a patio black spot removal service & stone bleaching service using sodium hypochlorite.

Sodium Hypochlorite is a chlorine compound often used as a disinfectant or a bleaching agent. It can be a great tool when performing black-spot removal on stonework patios as it brakes down the likes of lichens (black spots) in a short matter of time. This allows us to clean the stonework; leaving a spotless  immaculate finish it was also perfect for this job in particular because of the dullness of the stone, Cleaning the sandstone using the sodium hypochlorite Bleach’s the stone itself brightening and brings back all the natural colours to the stone as you can see in our video below.

Patio black spot removal service Kingston surrey kt2

Indian sandstone black spot removal service using sodium hypochlorite in Kingston surrey kt2 02037977471


We started by removing all Objects off of the patio in this case plant pots and chairs We then proceed to the first part of today’s service the patio cleaning.

Using one of our Honda cold pressure washers we clean the patio removing all surface dirt, algae and other impurities from the stonework Before giving it a good rinse down. after the clean was complete as we knew what would happen the black spots were still very Visible and even though the patio was clean, We knew we could get it looking a lot better using our stone cleaning techniques.


Always remember when mixing sodium hypochlorite with water to add the sodium hypochlorite to the water And not the other way around to prevent any splashback of sodium hypochlorite And always remember to wear protective clothing and Goggles As sodium hypochlorite is highly corrosive.

We start by mixing one part Sodium hypochlorite with two parts water In a large Bucket and giving it a good Stir; Sodium hypochlorite comes as 15% pure after diluting with water we get the solution to around 5% which is about as potent as your average household bleach. Using a stiff brush, we apply the sodium hypochlorite solution to the cleaned patio, making sure all parts are covered.

Once all areas are covered we leave down for around 30 minutes Letting the sodium hypochlorite do its work As soon as the solution is on the stonework it starts working immediately and you can see the colour changing before your eyes and the black spots breaking down fading away. After around 30 minutes we apply more solution to any areas where black spots are still visible As some are more stubborn to remove than others we carry on This process until all black spots are removed from the Patios surface Or at least faded enough to be removed by one of our Pressure washers in the final rinse down.

So we have Done the patio cleaning undertaken the patio black spot removal service now all that is left is to rinse down any solution Left on the patio.
During this final process we go back over the clean surface with the pressure washer cleaning again, this is where the stone brightening takes its place where the sodium hypochlorite solution has been left on the stonework soaking right into the surface, by the time it comes to giving its final pressure clean The patios stonework comes up about three shades brighter Restoring all the natural colours back to the Indian sandstone And leaving a delighted customer with a very clean and vibrant sandstone patio.

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