Reminder NOT to use uncoated copper through cement!

[WHPES]

Job yesterday - barn conversion with flood in a wetroom. Copper pipe had been run through a drylined adjoining brick wall. Due to the age and construction of the building, there is always slight dampness in these brick walls as they have no damp course.

The moisture content in the wall had caused the cement to eat into the copper causing a serious flood and damage to the fabric of the room. I had to dismantle part of a nicely tiled wall in a wetroom and saw the side out of a custom fitted oak vanity in order to access the pipe. It will take the builder and joiner at least 4 hours to put the house back to normal.

I replaced with plastic.

Everyone PLEASE remember that cement is corrosive to copper!

Whilst modern houses may get away with bare copper through cement (though it's bad practice), old properties won't.

Please protect copper pipework using coated copper or denso tape, use plastic pipe or knock out a brick and fill the space around the pipes with expanding foam! electricians tape is not enough as moisture can get between the layers.

 

[Centralheatking]

I was with a well known figure in the building industry for lunch last Monday and this question
came up and he said that there is no evidence that cement eats copper. It might attack
certain solders and the main cause of leaks is the expansion and contraction of elbow
joints in concrete floors. He said that the only real way is to duct pipework properly.

I have thought cement ate copper 4 the last 35 years - but this guy has a 2nd 2 none
reputation.

centralheatking

 

[Billy Bob Bob]

I was with a well known figure in the building industry for lunch last Monday and this question
came up and he said that there is no evidence that cement eats copper. It might attack
certain solders and the main cause of leaks is the expansion and contraction of elbow
joints in concrete floors. He said that the only real way is to duct pipework properly.

I have thought cement ate copper 4 the last 35 years - but this guy has a 2nd 2 none
reputation.

centralheatking

and he was clearly a idiot

 

[ecowarm]

Don't forget to sleeve it

 

[GQuigley67]

i usually just wrap duct tape around them, and sleeve where possible. Does denso allow for expansion ? bloody hate the stuff with a passion so hate working with it

 

[hammers4spanner]

I was with a well known figure in the building industry for lunch last Monday and this question
came up and he said that there is no evidence that cement eats copper. It might attack
certain solders and the main cause of leaks is the expansion and contraction of elbow
joints in concrete floors. He said that the only real way is to duct pipework prope



I have thought cement ate copper 4 the last 35 years - but this guy has a 2nd 2 none
reputation.

centralheatking

now dont tell me his name is bob and hes a builder ???

just a guess

 

[Best]

On damp walls especially, use a plastic pipe as a sleeve.
Cement that stays dry doesn't seem to do much harm, but better to keep copper pipes away from cement or bricks or just about anything they don't need to touch.

 

[Masood]

I was with a well known figure in the building industry for lunch last Monday and this question
came up and he said that there is no evidence that cement eats copper. It might attack
certain solders and the main cause of leaks is the expansion and contraction of elbow
joints in concrete floors. He said that the only real way is to duct pipework properly.

I have thought cement ate copper 4 the last 35 years - but this guy has a 2nd 2 none
reputation.

centralheatking

Interesting article here:

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

which supports his opinion. I'm inclined to agree, as cement is not acidic, it's alkaline, and as a general rule it's acids which oxidise metals, causing corrosion and "eating" them away, whereas alkalis tend not to. Either way, protecting copper pipes against movement caused by thermal expansion & contraction is essential, that's a given.

 

[WHPES]

I believe its more to do with the action of salt in the cement and bricks rather than the alkalinity