Hi guys! Somewhat new to this. I mainly do window cleaning but took the opportunity to do some pressure washing for a shopping center since they asked.
The area they want washed is white painted stucco (pourous and fragile to high pressure so softwash im guessing) and it’s covered in this black material that seems to be car exhaust but I’m uncertain (pictured below)
Fairly large, renting good equipment like hot water PW along with current equipment to do job.
Open to any recommendations, but mainly concerned on what the black staining is and what chemical will remove it.
My process is going to be softwash application of chemical and then hot water rinse? Maybe that’s wrong but that’s as far as I’ve got.
