Copper turning Black

Originally Posted By: jsieg
This post was automatically imported from our archived forum.



I have not come across this yet in any inspection I have done yet, but I would like to know what others have to say before I do.


I have been stopping by Open Houses & have been noticing that many of these homes have a copper roof over their bay windows. Almost all of them have been turning Black (not green, Verde, or what ever color you want to call it).

If I remember correctly this is caused by the sunlight against the copper covered by a lacquer finish that is not UV rated.
Am I correct???

What would be the way to correct this situation? (Other than the obvious replacement and/or stripping)


Originally Posted By: mthomas2
This post was automatically imported from our archived forum.



I have copper.org bookmarked:


"Due to varying fabricating procedures, some mills may coat coiled or flat sheet stock with a thin coat of anti-stain oil film. This film may give rise to dark purple or black surface colorations soon after installation and exposure. This is a temporary color phase caused by the thin oil film, which is quickly washed off by rain allowing the natural weathering of copper to proceed."

<http://www.copper.org/applications/architecture/fnshs.html>


Originally Posted By: Jay Moge
This post was automatically imported from our archived forum.



i see all the 40yr. old copper pipes in out boiler rooms turning black, but i think that’s from condensation and oil fired soot. it doesn’t come off on your hands, but it is black and copper. i don’t know if this is the same, but it may help. icon_cool.gif


Originally Posted By: jnosworthy
This post was automatically imported from our archived forum.



The situation you describe doesn’t need any correction. In my experience black is a part of a process. It doesn’t naturally turn green overnight. The black is the oxidation process taking place, reacting with chemicals in the air. I ocassionally drive past a very high copper clad church steeple I contracted about 10 years ago, I always look up. Nope … still not green yet … but then it doesn’t leak either. There is a way to actually speed the process by using a chemical wash, if you just can’t wait all those years.


Originally Posted By: Jay Moge
This post was automatically imported from our archived forum.



not to mention, i don’t know about you, but i’ve never seen a penny that was green and there copper. brown, to black yes but not green. probably has something to do with people handling them. but maybe if left alone long enough outside?..who knows. icon_cool.gif


Originally Posted By: troberts1
This post was automatically imported from our archived forum.



Is there any connections to galvinized pipe or galvinized pipe hangers present? This is a case of electroloses. excuse the spelling where did my spellchecker get off to? Anyway it is a cemical reaction of copper and zink which is what galvinized pipe is made of. also look for a galvinized duck or maybe a nail in contact with it, I have found this to be the case in every case that I have found this problem. icon_wink.gif


Originally Posted By: gbeaumont
This post was automatically imported from our archived forum.



Hi to all,


Copper will react differently dependent on the other elements it bis exposed to, for example acid rain or local manufacturing processes will have a marked effect on the color that develops over time.

![](upload://6vUQwuef4yvEOBv6Vo3gUaB86SW.jpeg)
The above are all naturally occurring variations

Regards

Gerry


Originally Posted By: mcyr
This post was automatically imported from our archived forum.



icon_smile.gif icon_smile.gif icon_smile.gif


I guess I have to put in my two cents here on this subject, for I have browsed over this topic to many times, I guess.

Cooper is nice and shinny when installed and looks like a million bucks or not far from it.

It takes about a year for the acidic rain to start the copper to turn green.

It generally takes like 20 to 30 years for the cooper to start turning green or even relate to a green tint of any sort. (Visit Quebec City)

I built a High School in 1989 with a copper roof cupula, and it is not turned green yet. This one took it's time to turn black, because it was recommended to coat the fresh copper with a clear laquer to help preserve it's new look.

If you wish to speed up the process in the black copper, it can be purchased as what you call Pitinaed Copper which is acellerated by the factory.

It turns black and looks like @#$%^ as far as I am concerned, and cost an arm and a leg. Some people like it. It is therefore, closer to the green state.

A copper penny will also turn green if left outside in the rain for a period of time that to me at the moment is unknown. I have found quite a few.

A penny found is one less penny to earn. ha. ha.

Hope this helps.

Marcel


Originally Posted By: mcyr
This post was automatically imported from our archived forum.



icon_smile.gif Correction,


It takes a year for the copper to turn black.

Sorry for the misprint.

Marcel