More concrete problems - MILDEW & RUST STAINS


  #1  
Old 12-27-05, 11:29 AM
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More concrete problems - MILDEW & RUST STAINS

Sorry to keep hitting you guys with all of these problems....
but I'm looking to renovate a cemetery that has been foresaken for years....
and looks like heck !
See pictures below.
http://www.javazon.com/bcmp-mess/images/DSCN3776.jpg
http://www.javazon.com/bcmp-mess/images/DSCN3777.jpg
http://www.javazon.com/bcmp-mess/images/DSCN3779.jpg
http://www.javazon.com/bcmp-mess/images/DSCN3793.jpg

I'm thinking muriatic acid followed by pressure wash with some bleach.
Not sure what to do with the stone entrance....sand blast maybe ?

Any and all advice welcome !
 
  #2  
Old 12-27-05, 11:46 AM
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More concrete problems - MILDEW & RUST STAINS

From the pictures it is difficult to tell what type of concrete you are dealing with and what the cause is.

The stains on the slabs appear to be someting like rust. Iron oxide is difficult if not impossible to remove. Similar stains can be lightened.

Do not apply any acid (it is more of a damage-all than a cure-all for concrete) until you have called a restoration company to look at the problem.

Dick
 
  #3  
Old 12-28-05, 02:54 PM
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Before trying acid I would try pressure washing alone. A very minimum 3,000 psi pressure washer, though, not a homeowner's 1500 psi unit. The small ones are great for washing your car, but are almost worthless for stained concrete. You'd be amazed what a powerful washer will take off (including your toe, no kidding!)
For the rust stains, try some CLR or similar product followed by pressure washing. I wouldn't get my hopes up too high though. Rust is a real pain to get out.
As to the mismatched sidewalks, if you want them to match, tear them out and have them all repoured at once. At $10,000 per mausoleum, the cemetery can probably afford to spend a couple thousand on a new walk.

Pecos
 
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Old 12-30-05, 08:14 AM
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Thanks but...

first of all, what is CLR ? What does it do ? Isn't TSP a good chemical for the job here ?

I don't understand why Muriatic Acid would not be appropriate here (I've used it successfully before to clean nasty tile floors) as long as it was properly "flushed" and removed after it did it's job.

Prior to pressure-washing, should an application of industrial strength bleach be applied to the mildew-impacted areas 1-2 days in advance or will the mildew be "blown away" by the high pressure treatment ?

Finally, do pressure-washers allow for additives to be injected during the application ? I would like to lighten and brighted everything.

Smash and re-pour the sidewalk ? Wow, I can't believe that is the only alternative !
Besides paint, what about high quality outdoor carpeting or something like that ?
 
  #5  
Old 12-30-05, 10:30 AM
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More concrete problems - MILDEW & RUST STAINS

CLR is available at the big box stores. It is different than TSP and works better than TSP for rust (if anything will touch rust).

Concrete and tile are two different materials. The acid will etch and roughen the surface of concrete while with tile to the problem os only the grout, which is slightly different han poured concrete. With acid, you run a large risk of variable appearance and litle likelyhood of touching the "rust" stain. If you insist on trying something different, go to an auto store and look for something that removes battary stains, but that may also ruin the surface appearance of the sidewalk.

Carpeting or paint would only be a temporary "fix" with continued maintenance. I don't think anyone really concerned with marketing a long term facility would go with a cheap, temporary fix if they are concrened with image.

In comparison to what you are selling and your concern with appearance tearing out may not be a bad option. - Wharever you do will affect the appearance or the facility for a long time.

Dick
 
  #6  
Old 12-30-05, 05:37 PM
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Are you even sure that the black stuff on the limestone is mildew? I doubt that it is, but it could be. Go ahead and bleach if it makes you feel better. It probably couldn't hurt anything. On another note, if you've got mildew on the limestone, what do you think would happen to outdoor carpeting? It would hold moisture and start to mildew long before limestone would, and I've never seen outdoor carpeting that looks good for an extended period. To me, it would seem kind of cheesy, especially in an application like a cemetery.

Pecos
 
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Old 01-02-06, 10:10 AM
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thanks, but what is the black then ?

re: "Are you even sure that the black stuff on the limestone is mildew? I doubt that it is, but it could be"

What is turning the cement black in certain locations then ?
 
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Old 01-02-06, 01:54 PM
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I don't know, but you see it on a lot of stone buildings. Have a restoration specialist look at it and tell you what it is. It may be mildew, but I don't think you should just assume it is and treat it as such.

Pecos
 
 

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