Last week one of the jobs we cleaned was a 110m2 driveway and Indian Sandstone Steps which came up like new. Unfortunately for the client, he had bought his own pressure washer and told his son to clean the driveway - ditto! They started on the Indian Sandstone Steps by the front door which was covered in Black Spot Lichen and Algae. I only wish I could have interviewed the clients' response when he said they tried to do it. With no joy whatsoever we were called in to clean the place up. We were able to successfully clean the driveway and steps in one day and was back to re-sand the driveway at a later date. The sandstone was chemically cleaned removing all traces of black spot lichen without damaging the surface using a pressure washer. The driveway was blasted and also chemically treated to remove the black lichen around and near the trees. I only wish we took close up pictures of sandstone before we started to clean it.