Client had new concrete laid Fall 2014. No salt was applied thru the winter. They have some discoloration (mostly brown / rust colored). Biggest problem is the apparent etching in the concrete. Something has taken some of the crème off of the concrete. No one can lay claim to doing it, or what may have caused it. Was not there at completion of job, so it's not from job site work. The area slopes, so they are definitely runs in the concrete. I figure that something acidic has dripped / spilled onto the concrete. Something in leaky trash bags maybe?
This looks like a working of the concrete or curing problem more than an etching problem, but it's always hard to tell from photos. Be careful how far you get in to this. There is nothing that I know of that can solve this problem, I'd love to know if someone else does. Personally it looks over troweled in areas but the pattern is weird. Do not pressure wash this concrete with anything but a light rinse or it will etch. I don't pressure wash at all until it has cured for 1 year, and even then you have to be very careful for a year more with things like gum and stain removal that you have to really "get on."
The rust stains are a different story, maybe Craig at T9 would have some insight, but with the other problem present, I'd be wary. This seems like a problem for the concrete contractor more than you. The good news is that finish variances like this tend to fade with time.
I really don't like getting involved in situations with other contractors who are having issues, especially with commercial properties. I have had too many bad experiences. I'd rather sell and do 8-12 residential cleanings with that effort. That being said, if you find something that works well for a certain situation, you can be a contractor's best friend. I have a garbage truck company and an asphalt paving company that each call me 15+ times a year.
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Chad A. Eneix, President, Water Dragon Inc. chad@waterdragoncleaning.com
Thanks Chad. I told the client about the same thing--this is your concrete contractors problem. I am not taking the job, but I also told him that I have a network of companies that I can ask for some input to give him some ideas that I may not know. Great selling point for future opportunities with them.
The other thing I usually do in this case is downplay the problem a bit. They are looking at it with a super critical eye, as are we. If you take 10 steps back and look at it from the curb, I bet to the average customer/ pedestrian it looks great. A summer of foot traffic, and this may not even be that noticeable any more. You could also give them a proposal to put a sealer on that brick trim to make that really "pop." It will take attention away from the concrete issue.
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Chad A. Eneix, President, Water Dragon Inc. chad@waterdragoncleaning.com
