Shoe Prints on Concrete

Has anyone ever noticed shoe prints after a couple passes with the surface cleaner? I don’t think this is something I did but wanted to get some feedback from the experts here.

Equipment - 5.5/2500 PW, 16” WW SC, 1,000 PSI tips
Pretreatment - around 1% mix downstreamed
Post treat - same as above

Newer concrete poured 2 years ago.

No visible signs of etching or milky runoff noticed.

This section of the patio is pretty much in full shade.


You’re cleaning concrete at 1000psi?

If that’s what you want to call it…“cleaning” lol



Sep '20

Dial down the pressure with the nozzles on your surface cleaner. The other guys here are better sources of info than me, but you may get by with 800psi. You just need to consult the nozzle calculator.

Or, just make an educated decision and pass.:+1:

Oh where do I start.

You get to deal with this one, your post, LOL.


Ok let’s break this down.

When you say shoe prints, can you elaborate?

Gladly, thanks for your help:

I probably didn’t give the best description. What these look like are discolored areas that are the perfect shape, size and tread of someone’s shoes or boots. They are even with the surface and not recessed at all. They discoloration is very subtle - a darker grey compared to the rest of the area,. To me it looks like someone walked on it before it was ready just enough to disturb the cream coat. This area is in complete shade. I’m thinking maybe the homeowner ventured out there and this area wasn’t quite ready for foot traffic. I’m thinking (hoping) that the cleaning just exposed these imperfections. This was the only place on the patio I noticed this.

Possible, might try post treating stronger in that area.

Typically 2+ year concrete is fine with 2500psi nozzles, that’s why we were a little flummoxed when you mentioned 1000psi.

are you rinsing well and in short intervals? plus, if the shoe prints aren’t yours, there not much to worry about. it’s possible it’s removable, it just depends on what it is. if it’s been walked in somehow before its been cured, theres not much you can do but maybe etch it evenly, which could be a whole other problem.