Concrete damage!

I went and looked at a customers driveway last week, he used Scotts fertilizer and didn't blow his driveway off after applying the Scotts.
It's been raining every day in FL, so now he has rust stains. Itold him no problem I have a product that removes the rust stains. He than explained that he tried chlorine, muratic acid and a rust remover from a home improvement center. When I arrived at his house and walked up the driveway I was shocked, this is the worst damage I have seen in thirteen years in business. Acid burns, zero degree damage and pavers with bleached out color. The customer now says he also hired a pressure washer who used an acid.

I explained that it looks like permanent damage but would try F9 Bacr to remove the rust stain and see if it would lighten the acid burns. I was able to remove most of the rust stains but no luck with the acid stains. I was able to blend the zero degree marks a little. A lesson learned, some times you just have to walk away and tell the customer they have permanent damage.


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Good decisions Mike.

I always point out existing damage and take pics and sometimes I will walk away from some jobs as sometimes the concrete is very weak and cannot handle much pressure (bad pour) and sometimes it is just that the previous contractor just used way too much pressure.

Always better safe than sorry.



Call me next time you have damage like that. We deal with this all the time. The Hcl created an amorphous paste in the concrete. You'd need to go high pressure, slow over the concrete with your surface cleaner 2-3 times in different directions to get it out. Once the surface is dry and free of white paste, you'll be able to remove the deep orange acid burn from the hcl (muriatic acid). If there is paste left in the concrete you can still remove topical rust but not deep chemical burn.

By using your surface cleaner over the surface several times (different directions too) you'll be able to even some of the damage. The etching of course if permanent but you can make it a little better. For deep orange burn you need to go heavy on F9 too.

As your last step it's important to wet the two applications of F9 and broom them evenly. This will aid in deeper penetration before you rinse.

Scott Stone

New member
Craig gave me some F9 a few weeks ago. We finally used a little of the sample last night on some terrazo and in a parking garage. I was speechless. If you deal with rust stains and such, it is the bomb.