I've just had a request to do some pressure washing of the exterior of 20+ new build prefab style homes, basically the want any excess mortar and traces of scaffolding marks cleaned off prior to the new clients moving in. They currently use a cleaning company who pressure wash the exteriors but also use some sort of chemical to remove the mortar.
Anyone any ideas as to what this chemical could be, I was thinking probably a brick cleaner or similar? We have a 4000psi petrol pressure washer and a 3.6m extended lance