When it comes to pressure washing a good deal of what we do happens to be “flat work” and that would be basically cleaning anything from parking structures, sidewalks, parking lots, runways, or basically anything which was flat. We had special devices called Hydro Twisters, but we also use pressure washers with long wands and 45-degree tips. Okay, I’d like to talk to a little bit about the science behind power washing on flat horizontal surfaces.
Perhaps you’ve heard of the swash zone, this is the part of the beach between the dry area of the beach and the surf. It is that place where you can walk and only worry about getting your ankles wet as the water is only a few inches high. It turns out in the swash zone sediment is transported quite easily and distributed evenly on the beach. Now then, this has important applications for concrete cleaning. If you are using any type of cleaner, and a pressure washer or a Hydro Twister you are interacting with the surface in almost same way.Concrete Power Washing Hanover is one of the authority sites on this topic.
The pressure spray acts just like the power of the ocean forcing the water along the beach. As that water flows up the slope and comes back again, this is something very similar to using the pressure washer up against the water you have just sprayed. In fact the mathematical modeling works exactly the same way. The only difference is you are changing the direction of spray as you move the wand back and forth, but what is happening on the surface is essentially the same thing. The force hitting the actual concrete might be greater, but the swirling flow of the water is also mathematically predictable.
One interesting thing which happens when doing flat work is when you get to a piece of concrete which does not drain properly, a place where the water puddles. Agitating the water in that area only causes more sediment to stay suspended, where it will eventually fall back and stay on the concrete due to gravity after you leave. That is why at many pressure washing companies, the operator will do those areas first and spray away from those puddle regions. Of course, that makes sense as it is and should be considered a best management practice for anyone engaged in this type of cleaning.