[mgnyjcws]

Hired out a company to come power wash and re-stain the cedar siding on 6 year old home. During the process of power washing, the detergent that was used on the siding has discolored many of the galvanized steel panels that are on the home as siding/cladding/soffit.

The company tried to clean the staining on the panels with dish soap to no avail. I don't have a good feeling about this :0:surprise:

Anyone have any experience with this sort of thing?

Pictures attached.

Any help would be appreciated.

 

[mark sr]

What did they use to clean the siding? Was there any type of coating on the galvanized panels? Hopefully the company that did that is insured.


If the steel can't be cleaned so that it all matches the only solutions I know of are replacement or paint.

 

[joecaption]

Try using some white vinegar.

 

[mgnyjcws]

What did they use to clean the siding? Was there any type of coating on the galvanized panels? Hopefully the company that did that is insured.


If the steel can't be cleaned so that it all matches the only solutions I know of are replacement or paint.

SUPERDECK REVIVE from SW was the product what was used to clean the siding.

Yes, i have found a bit on info online about restoring the panels, but i am not overly optimistic.

 

[mgnyjcws]

Try using some white vinegar.

Will do. That would be great if that took care of it. I will let you know!

 

[mark sr]

While it would be good for you to figure out the fix you should make the cleaning company do the work!

 

[mgnyjcws]

While it would be good for you to figure out the fix you should make the cleaning company do the work!

Yes, for sure. Test one - White vinegar... Looked as if it was cleaning it off, but once it dried, it did not help.

I found a resource online that has some options, but i am not holding my breath. sigh...

 

[kwikfishron]

Yes, for sure. Test one - White vinegar... Looked as if it was cleaning it off, but once it dried, it did not help.

I found a resource online that has some options, but i am not holding my breath. sigh...

I don't think there's anything to clean off. I think what they did either took the galvanizing off or compromised the chemical compound of it creating the color change.

I sure hope I'm wrong... Good luck.

 

[Old Thomas]

There is spray paint for restoring classic car gas tanks and it matches a galvanized finish. If all else fails, spray it.

 

[joecaption]

In over 50 years of working on houses this is the first time I've ever even heard of anyone using galvinized metal for a ceiling, so I feel bad for the company doing this because I'm sure they also have never had to deal with it before.
Rustoleum makes two different types of spray on galv. paint.

 

[ChuckTin]

Personally I think you're f'd. Sorry for you. That cleaning solution has affected the surface of the metal. Negatively for you. At this point, IMHO, your best bet is a wash for all the galvanized that will even out the look of the metal.

 

[SPS-1]

The active ingredient in Revive is Oxalic acid dihydrate. The forum's resident chemist (Nestor) is no longer around to explain if it would eat the zinc galvanizing. Maybe there is another chemist out there ???

But my guess is that its not "dirty", its been chemically effected. If worst comes to worst, you can put a line of painters tape on the ceiling, maybe 15" from the wall and paint the discolered area. You will get different opinions on whether to try to match the color or contrast it. But note that paint does not stick to galvanized steel very well, so use an appropriate primer.

 

[SPS-1]

THIS chemist suggests the reaction formed a zinc oxalate layer over the panel. But I am not sure how/if its going to come off.

I believe oxide layers can be pretty tough, so it might take sandpaper to remove it. It would be a challenging task to abrasively remove the oxide layer without removing the zinc below it. Maybe buffing it out with a power buffer and a buffing/cutting compound ????


.

 

[Porsche986S]

It looks like the panels are screwed on , can you remove the screws and flip the panels over exposing the other side ? Assuming the damage did not get to the other side .

 

[Colbyt]

It looks a lot like galvanized parts that I run through the dish machine to prep them for painting so I seriously doubt there is anyway to remove it.


Sorry that I don't have a more optimistic opinion for you.

 

[HandyAndyInNC]

You do not want to use an acid(vinegar) on steel. And I suspect that some idiot that did not know what they were doing used a cleaner with acid in it to wash the cedar. Another huge mistake. Wait a few weeks and you will see the cedar turn color. Colors that you do not want on a house. That will do exactly what you see. Acid and wood, acid and metal do not mix well. Grade school chemistry. If you have to wash cedar, use water only, and water with a few drops of very mild detergent like dawn, or one that is eco friendly like method. And you wet the wood and brush it, never use a power washer on any wood, especially wood on a house.

That is now etched into the metal. You will have to sand it off, start with 180 and go from there. Just depends on how shiny you want the metal to look. Nice lite pressure using an orbital sander. You also wet sand it by hand.

 

[SPS-1]

Acid and wood, acid and metal do not mix well. Grade school chemistry.

Oxalic acid is commonly used a wood brightener. In my opinion, it doesn't clean very well, and doesn't brighten, but many of the more aggressive deck cleaners recommend the Oxalic acid brightener to restore the PH to the wood before staining. I clean, brighten, and stain my deck each spring.

 

[SPS-1]

That is now etched into the metal. You will have to sand it off, start with 180 and go from there. Just depends on how shiny you want the metal to look. Nice lite pressure using an orbital sander. You also wet sand it by hand.

I don't think the zinc will be more than a thousanth of an inch thick. 180 grit will go through the zinc and into the steel in no time. Need FAR finer grit is my guess.

 

[carpdad]

Guessed about the chemical reaction and not even close to the materials used but makes sense. I guessed nickel for galvanizing and the cleaner as something like bleach.



Since wetting made it look better, how about a clear coating of some kind? Try a spot with wax? I would not coat the whole thing with polyurethane since I'm not sure if urethane may start peeling. If not wax, a liquid that makes wood floors more shiny? Something like these that will not peel in sheets or flakes and easy to remove if must.

Or chemical that will turn the whole thing dull or live with the aged look.:smile: The sheetmetal may had a coating to keep it look shiny and maybe it's the coating that turned/removed.

 

[mgnyjcws]

The active ingredient in Revive is Oxalic acid dihydrate. The forum's resident chemist (Nestor) is no longer around to explain if it would eat the zinc galvanizing. Maybe there is another chemist out there ???

But my guess is that its not "dirty", its been chemically effected. If worst comes to worst, you can put a line of painters tape on the ceiling, maybe 15" from the wall and paint the discolered area. You will get different opinions on whether to try to match the color or contrast it. But note that paint does not stick to galvanized steel very well, so use an appropriate primer.

Thank you for the information.

Update: The company came back out and tried a cookware cleaner from Royal Prestige when they came back out to resume work and it seemed to clean it up to some degree. Certainly didn't look new, or like they put much effort into the cleaning, but i am certainly happy it moved the needle in the right direction.

Got a BIGGER problem on my hands now... So, when this came up, the wife and i also talked about how we have never really cleaned any of the panels on the home and that it would be nice when the staining of the home is complete, for us to try to clean the panels. They have always had some small, scattered, white stains on them that we were hoping to get cleaned off.

So i think back to the suggestion of White vinegar. In fact, i had even tied using it at the very bottom of the staining the workers caused to see if that would be a viable option to clean up THAT issue. It didn'd alter those markings but i had also read online that it really does work on the hard water stains. I go out to the side of the house, a more inconspicuous area and give it a test. It works! The little white spot looks gone! So, i proceed to wipe down the length of the panel where the other white areas are built up....annnnnnd... within 10 second i could see a HUGE difference. Not only did it remove the white marks, but i COMPLETELY changed the finish on the panel. So frustrating... So i go back, look online and of course it should be diluted. So here is what i am dealing with now (PHOTO ATTACHED)

Obviously i feel like an idiot... I have no idea what to do now. I have rinsed it off, no change. Its on the side of the house, and there are probably 15 panels that are on that side of the home. First thought was to use a diluted water /vinegar solution, try to clean the entire side of the home, so it would blend in... but at this point i am scared to touch it and make it any worse.

Any ideas?

Thank you all for the input.