Concrete is a very durable surface, but it still needs regular cleaning to keep it looking it’s very best. Over time it will darken and lose it’s light and bright appearance. Additionally, algae and moss build up on concrete cause slip hazards, making it an unsafe area.
There is more to cleaning concrete than just using high pressure. The age and condition of the concrete is very important to take into consideration. This will determine the strength of the solution and the pressure used to clean it. Too much pressure will permanently damage concrete.