Black Spot Removed from an Indian Sandstone Patio in Bolton-Le-Sands
This Indian Sandstone Patio in Bolton-Le-Sands near Lancaster had not been cleaned successfully for several years. Although the owner had power washed it on occasion, that won’t rid you of Black Spot, Mould, Lichen etc and this will build-up over the years. It does clean the stone up to a certain standard but at some point, it will need further treatment.
My client had now reached this point and decided to give Tile Doctor a call to have it renovated. We discussed the Patio which ran around the house and calculated that it measured approximately 60m2. With the measurements and a summary of the issues I was able to work out a quote which they were happy to accept.
Removing Black Spot from an Indian Sandstone Patio
To improve the appearance of the stone I started by giving it a power wash to remove the general grime and dirt. I used a top of the range Karcher Pressure Washer for this which can apply up to 20 bars of pressure. The machine also comes with a spinner attachment results in a much more even clean than simply using the spray head.
The patio was left to dry for thirty minutes before applying neat Tile Doctor Patio & Brick Driveway Cleaner. Please note this is a very powerful product meant for professional use so if you’re using it always wear gloves and protective glasses. You leave it on the stone for ten minutes or longer before working it in. The directions on the back of the bottle say recommend leaving it for two to four hours, but its general advice. Personally, I find it is best to test the timing on a small inconspicuous area first, leave it on for say ten minutes then add a bit of water, scrub the surface and if the Black Spot disappears then that is all the time you need. If the stain is stubborn, increase the time. The two to four hour recommendation is really for difficult Black Spots that have become ingrained into the stone and then the product needs longer to digest the stain before it can work.
Once that was done, I used the power washer on low pressure to wash the products off the stone and into the sewerage drain, a wet vacuum comes in handy for this. Don’t dispose of it into the grass or planting areas as the strong chemicals in the product could upset them. Many properties have a soak away to capture rainwater from gutters, so you need to make sure it’s the sewage drain you are using.
As you can see on the pictures, this product really does work and got rid of the Black Spot completely. To maintain the patio a regular jet wash was recommended, the household versions are ideal for keeping it clean and tidy.
Due to the size of the Sandstone patio the whole process took around six hours to complete. Once done though the patio looked transformed and was all ready for a barbeque and some guests. Hopefully, it will stop raining long enough for this to happen.
Source: Professional Restoration of an Indian Sandstone Patio in Lancashire