plaster skim corrode copper?

[Mgrant]

Can finish plaster/ plaster skim corrode copper, if any is dropped on a pipe and not cleaned off?

 

[thompsonbrown]

Seen copper pipes buried in walls and skim coat as corroded through them.

 

[ShaunCorbs]

Yes it can

 

[Best]

I am surprised that replies have been that finish plaster corrodes copper.
Any copper pipes I have ever seen covered in finish plaster have been perfectly good order.
The danger is any dampness and particularly sand and cement or the solid walls (brick, stone or concrete block).
If it is a dry wall, like an internal wall, then it is still advisable to put something as a barrier over the copper pipes, such as electrical insulating tape. Sleeve other pipes.
Copper pipes have been plastered with finish where they come out of walls and ceilings for years and good as new.
One place I do not like bare copper pipe is coming out of tiled floors, whether on solid or wood floors. I prefer the tile to be drilled larger than the pipe diameter and pipe collars fitted so no grout used. Another option is to use insulating tape on part of pipe coming out of floor.

 

[ShaunCorbs]

I am surprised that replies have been that finish plaster corrodes copper.
Any copper pipes I have ever seen covered in finish plaster have been perfectly good order.
The danger is any dampness and particularly sand and cement or the solid walls (brick, stone or concrete block).
If it is a dry wall, like an internal wall, then it is still advisable to put something as a barrier over the copper pipes, such as electrical insulating tape. Sleeve other pipes.
Copper pipes have been plastered with finish where they come out of walls and ceilings for years and good as new.
One place I do not like bare copper pipe is coming out of tiled floors, whether on solid or wood floors. I prefer the tile to be drilled larger than the pipe diameter and pipe collars fitted so no grout used. Another option is to use insulating tape on part of pipe coming out of floor.

Plaster/finish paster not just finish pink skim

 

[Best]

Plaster/finish paster not just finish pink skim

Yes, I know that sand and cement plaster mix is lethal to copper and probably similar mixes, but I know finish (grey or pink) skim and bonding plaster - (which is I think basically finish with mica in it) do little harm to copper.
Although I cover or sleeve copper everywhere. So much easier to remove plaster from around pipes in the future also.

 

[plumben]

ive seen copper pipes start to corrode after the plasters have covered them weather it was just from the dam and damp atmosphier im not sure, but personally i'd cover any pipes if there in the skim and if there plaster on the pipes just pull it off once the plasters finished

 

[Best]

ive seen copper pipes start to corrode after the plasters have covered them weather it was just from the dam and damp atmosphier im not sure, but personally i'd cover any pipes if there in the skim and if there plaster on the pipes just pull it off once the plasters finished

Yes, any damp, even a few drops of rain will stain the new copper.
One tip I would recommend, is to put cuttings of 20mm round conduit or 3/4" overflow pipes over 15mm copper tails coming out of floors and walls and tape it to the end of the copper. Keeps the copper brand new and plasterers won't do it harm.

 

[Fallon1982]

I never chance it. Always wrap denso tape around copper that is buried in concrete, plaster etc...

 

[macackau]

I never chance it. Always wrap denso tape around copper that is buried in concrete, plaster etc...

Yep, messy stuff but I've used if for years with no problems. Have a Stanley knife in the van just for cutting denso

 

[stevetheplumber]

quick tip buy a spray can of carb cleaner spray from a motor factors cleans denso of a treat

 

[macackau]

quick tip buy a spray can of carb cleaner spray from a motor factors cleans denso of a treat

Thanks for that tip!

 

[lame plumber]

one coat plaster has lime in some makes evil stuff for copper.

 

[Mgrant]

I am surprised that replies have been that finish plaster corrodes copper.
Any copper pipes I have ever seen covered in finish plaster have been perfectly good order.
The danger is any dampness and particularly sand and cement or the solid walls (brick, stone or concrete block).
If it is a dry wall, like an internal wall, then it is still advisable to put something as a barrier over the copper pipes, such as electrical insulating tape. Sleeve other pipes.
Copper pipes have been plastered with finish where they come out of walls and ceilings for years and good as new.
One place I do not like bare copper pipe is coming out of tiled floors, whether on solid or wood floors. I prefer the tile to be drilled larger than the pipe diameter and pipe collars fitted so no grout used. Another option is to use insulating tape on part of pipe coming out of floor.

So abit of dried plaster skim is unlikely to corrode a copper pipe. Or were pipes exit ceilings and are plastered up to.

 

[Best]

So abit of dried plaster skim is unlikely to corrode a copper pipe. Or were pipes exit ceilings and are plastered up to.

As far as I see, the finish itself is fairly harmless. That said, you don't really want any damp plaster or any chemicals on copper pipe. Even the rain makes a right stain on new copper.