Concrete cleaning - Who can lay it on me and help out?

Hey guys, I have a surface cleaner for the first time this spring and am looking at
doing a bunch of work with it. I already have a number of banks lined up for their
drive-thru pads.

I am not new to pressure washing, but I am new to concrete cleaning. Does anyone
know where I can go to read up on concrete cleaning? Better yet, is anyone willing
to spend some time on the phone with me to coach me through the process?

I have a 5.5 gpm 4000 psi machine within a trailer set-up so you know.

Thank you so much for any help you give me.

Call me Monday. I’ll help ya out.

Try this one

JC has a good point. Don’t take it the wrong way, there is just much more info archived on PTState.

I used to do a lot of google searches because they seemed to pull better results than bbs searches.


You can read for days

Feel free to ask specific questions here, Kyle. This way questions and answers can be cataloged and can be of help to others, too. The more content on PWRA the more useful the search feature is.

You’re still welcome to call Monday, though, too.

PT State is a 100% BS-free board. There is no agenda being driven and Bob is as straight a shooter as walks the earth.
Asking questions here is good, too. Like Micah said it helps build the database.

I’m interested too.
I don’t have a heated machine. Is that a problem?
What type of solutions/mixtures do you use?
Can gum come of with a cold water unit?

Thanks for all the help already guys. Micah I was hoping you were going to chirp in,
you were one of the guys that I wanted to call on this. Thanks for the offer, I will call
on Monday.

I also think it is a good idea to get more content on this site related to concrete cleaning.
So here we go to get started…

Many charge by square foot from what I’ve gathered. What is a good price range for that?
I am doing drive-thru pads at a few banks and they’ve never been done.

The majority of the concrete is alright but then there are areas that have an inch of oil and grease.
How do I price when areas of concrete have that much grease in one area?
How do I clean a concentrated area that has that much build up? I mean it looks like I should go with
a spade to scrape it off first.

What kind of tips will I need for my surface cleaner? And when should I replace my tips because of use?

I hear a lot about “tiger stripping”, what causes this?

Is all concrete treated equal? Will one driveway leave tiger marks when the next one will not?

Thanks guys!

Once I am done with the surface cleaner should I coat it with anything?

If so, what do I coat it with and do I need to wait for the concrete to dry
before coating?

[QUOTE=ClearVisionWindows;8378]Once I am done with the surface cleaner should I coat it with anything?

If so, what do I coat it with and do I need to wait for the concrete to dry
before coating?[/QUOTE

Generally, coating or sealing concrete sidewalks, driveways, drive-thrus, etc with any kind of quality sealer that would last more than a few months would so expensive it is usually cheaper to simply clean the concrete periodically. Besides the concrete is still going to get oil on it, it is still going to get gum on it, and dirt is still going to get on it. So it is still going to need some kind of cleaning anyway. Also, you will never 100% of the oil good enough to get a good bond for the sealer anyway.

Amen Len…

I’ve basically told customers the same thing 3 times this week. Everyone thinks sealer is magical or something.

[COLOR=#0000ff]Check out my answers in blue.[/COLOR]

[Is all concrete treated equal? Will one driveway leave tiger marks when the next one will not? On rare occasion. You will sometimes see that lower grade concrete is used. This concrete is commonly referred to as “patio concrete”. It may be fine for small patios, but not for commercial settings. If too much pressure is used, it will harm the concrete. This is not extremely common, but it’s good to always start cleaning off to the side or in a corner, not right at the front door. I don’t think you’ll ever have this problem at a bank lane though.]

In my previous career I was a bridge and heavy foundation superintendent for 32 years. I figured up once that I have poured over one million cubic yards of concrete. I feel confident that I have more experience with concrete than any other pressure washing contractor on here. I can tell you most definitely all concrete is not all the same. I promise I will try to write up something about the differences in concrete that determines the strength of it. However, concrete strengths can range from a Class B mix that will attain 2,000 psi breaking strength to Class A at 3,000 psi, Class D at 4,000 psi, all the way up to Class X that is as high as 9,000 psi. The higher the strength of concrete, the higher the cost. Due to cost and because there are very few homeowners that know the difference in concrete the builders will go with as cheap a mix as they can get by with.

In localized commercial concrete, it may be a little tougher to get away with a 2,000 psi mix due to heavier traffic that the concrete may be subjected to so they will usually go with a 3,000 psi mix. Still even though they may use a stronger mix, contractors can make a lot of mistakes that can lower the attainable psi while they are putting the concrete in place. More on that later too.

Then in commercial chain construction like Lowes, Home Depot, Chain Restaurants, and the like, they may use a 4,000 psi mix and the contractors have a specific set of standards and procedures they have to adhere to to make sure the concrete is placed in a manner that the concrete will reach its highest possible breaking strength.

I’ll try to write all this up so everyone will know about concrete and how they may need to match their nozzles to match the concrete strength they are cleaning as well as the machine they are using.


this is what im talking about! great thread.

Len, where do you plan on laying all this out? I do not want to miss this!