Buried copper pipe with Thistle Gypsum Bonding Plaster - help!

[stoobloo]

I can't seem to find anything solid that clearly states whether or not unprotected copper pipes will be corroded by gypsum based plaster, in my case bonding plaster.

Some say it does (most), some say it doesn't.

If it does how long are we talking before the copper pipes fail and leak?

 

[aveatry]

I am interested in this too because I did the same with a copper pipe for a shower but I used thistle one coat or something like that. I cant remember but It was white and could be put on really thick.

 

[HERTS P&D]

'With their high alkalinity levels, cement and plaster can corrode copper pipes. The reaction between the two materials generates copper oxide which accumulates in the tubing and blocks it off. Both on its exterior and interior, this erosion will cause leaks or further damage to your plumbing system.'

Copper pipework should always be protected.

Andy

 

[aveatry]

'With their high alkalinity levels, cement and plaster can corrode copper pipes. The reaction between the two materials generates copper oxide which accumulates in the tubing and blocks it off. Both on its exterior and interior, this erosion will cause leaks or further damage to your plumbing system.'

Copper pipework should always be protected.

Andy

Can you tell me please that its not so bad in plaster than it would of been in cement --- please.

 

[HERTS P&D]

While it is possible to bury a copper pipe with Thistle Gypsum Bonding Plaster, it's important to be aware that the plaster's slight alkalinity can potentially corrode the copper pipe over time, especially if the pipe carries hot water and experiences significant temperature fluctuations causing expansion and contraction, which could lead to cracks in the plaster around the pipe; it's generally recommended to use a protective sleeve or plastic trunking around the copper pipe before applying the plaster to minimize corrosion and cracking issues.

Andy

 

[aveatry]

While it is possible to bury a copper pipe with Thistle Gypsum Bonding Plaster, it's important to be aware that the plaster's slight alkalinity can potentially corrode the copper pipe over time, especially if the pipe carries hot water and experiences significant temperature fluctuations causing expansion and contraction, which could lead to cracks in the plaster around the pipe; it's generally recommended to use a protective sleeve or plastic trunking around the copper pipe before applying the plaster to minimize corrosion and cracking issues.

Andy

Well that makes me feel a lot better hope it does stoobloo too.
Mine is a cold feed for an electric shower.
Are they referring to cracks that will let air get to it so otherwise it will not corrode if no air gets to it.
In future will be protecting copper pipe, but with what- is electricians insulating tape good enough. If passing through a wall or under the floor in concrete then inside a plastic pipe probably but chased in a wall for a shower i dont want to add too much thickness to the copper.

 

[polesapart]

Plumbing: TechCorner - Is There A Problem With Embedding Copper Tube In Concrete?

It is completely acceptable to bury/embed both hard drawn and annealed copper water tube in concrete. Decades of satisfactory service experience with the use of copper tube for in-floor radiant heating systems, water distribution systems and snow melting systems attest to the compatibility of...

copper.org

 

[oldbuffer]

Four paragraphs on in the article quoted by polesapart its states:

According to the Portland Cement Association the interaction of copper with both dry and wet concrete should not cause a corrosion concern. However, copper should be protected when it comes in contact with concrete mixtures that contain components high in sulfur, such as cinders and fly-ash, which can create an acid that is highly corrosive to most metals including copper.

 

[trojanhawrs]

I've seen duct tape used to protect copper to be buried.

 

[dilalio]

I've seen duct tape used to protect copper to be buried.

And that's how I do it.

 

[Notch7]

I used Denso tape for my buried shower pipes.

Awful stuff to use, sticky as F

 

[dilalio]

I used Denso tape for my buried shower pipes.

Awful stuff to use, sticky as F

No longer approved for gas pipes so, maybe also corrosive for copper too.