Galvanised Pipe Replacement

[RandomRando]

Hey folks.

So i knew I needed to replace the Galv. Piping at some stage... I just didn't know how immediately soon that would need to be until I got inquisitive after seeing some guest bathroom wall tiles lifting. Attached is what I found underneath... my main hot water exit from the geyser that feeds the guest bathroom and kitchen, as well as ensuite shower and vanity. Fortunately the ensuite is a Tee before the galv connects to the copper direct to geyser.

I've now noticed other areas where tiles are raised / cracking in where I suspect the piping goes to the various outlets. So I have no choice but to remove the rotting pipework, lest it expands more in future, causing more plaster cracking / tile cracking.

This now goes to the top of the list before it springs a leak when we are not around. Rather be in control of the repair, than react when it pops. Fortunately, we can make do with only the ensuite bath, so i have the space and freedom to work.

The plan is as follows:

1. Drain the Geyser
2. Disconnect the galv from the 22mm copper pipe, leaving the geyser and blank off, so only the ensuite bath has supply.
3. Install a shutoff valve on the hot water outlet for future ease of maintenance as opposed to draining the entire geyser.
4. Open the walls and remove the old galv. to replace with 22mm copper.

Now while I've done plumbing before using conex, (copcal was a long time ago so I'll need to "refresh my soldering), I've never even blinked when it came to putting copper in walls. Chase, lay pipe, close with plaster. Done. Live happily ever after. Seen it plenty too.

However, a colleague at work recently had some work done due to a leak in their house. Turns out, they had a "pinhole" leak which is caused by the copper pipe reacting with the lime in the cement?! They didn't say what the solution is to this issue, other than the leak got fixed and they have a lekker hole in their kitchen wall. Lol.

I plan on fixing this once. I do not intend to reno the bathrooms with new tiles after wall chasing, only to get pinhole leaks and go through this again when im old and more grey. So my question is, to the plumbers out there:

Do you protect the copper with anything to avoid direct contact with cement, when laying new pipes in walls, or is industry practice to gooi it and close with plaster?

I've only ever used Denso on external fitting & flanges exposed to the elements or buried, never on a pipe going in a wall. Further, any sort of spacing / insulation would surely deteriorate over time and risk hammering if pipes aren't encased? Is denso my answer here?

TiA.

 

[B-1]

Just buy class 2 tubing and it will outlive you. People are installing class 0 or 1 in walls to save a buck and then wonder why they have issues.

The pinholes also tend to come from the water inside the pipe usually from borehole water high in salts or a low pH.

 

[rh1]

Just buy class 2 tubing and it will outlive you. People are installing class 0 or 1 in walls to save a buck and then wonder why they have issues.

The pinholes also tend to come from the water inside the pipe usually from borehole water high in salts or a low pH.

My home only had class 0 pipes, the quote was so expensive, it is cheaper to wait till they burst and pay insurance the excess for replacement and repairs.

 

[acidrain]

Why not try CPVC pipe? Recommended alternative for copper and more cost effective

 

[RandomRando]

Just buy class 2 tubing and it will outlive you. People are installing class 0 or 1 in walls to save a buck and then wonder why they have issues.

The pinholes also tend to come from the water inside the pipe usually from borehole water high in salts or a low pH.

Thank you.

I didn't know that corrosion came from the water internally. I was under the impression that it was due to it reacting with the cement itself over time - similar to galvanised only not as severe.

Nor did I think that the different classes would have much impact, apart from the obvious thickness qualities only delaying the inevitable but then again, I didn't know how fast this occurs either. As mentioned, I've never even paid attention to this on previous work done on the family home- ignorance is bliss!

Jozi water is pretty hard, so don't think it's high in salt lol.

 

[RandomRando]

Why not try CPVC pipe? Recommended alternative for copper and more cost effective

I don't have much experience in PEX pipe although I did consider it due to the obvious cost implication & no soldering required for bends.

Just a bit sketch about the females that need to be at the outlets for taps and such to connect to. I'd rather have a soldered, solid fitting there than a compression fitting that's "bitten" into the pipe that could strip?

I dunno. I have only ever worked with HDPE, copper, galvanized and 'polypop'. Always used HDPE for main lines, polycop for temp solutions, Galv or copper for permanent external/ internal work I've done overv the years.

I'm not a plumber by trade, despite previous experience, so there are niches within the theory I'm not familiar with.

Also, I do have the superpower to over think things to the nth degree. Both a gift and a curse and why ignorance truly is bliss.

 

[RandomRando]

My home only had class 0 pipes, the quote was so expensive, it is cheaper to wait till they burst and pay insurance the excess for replacement and repairs.

This goes against my very nature and I wouldn't be able to live with myself knowing I half assed it.

I'm fortunate enough to have enough skill to do this myself thanks to my trade background and prior work experiences. Plumbing team coming in to re plumb a house is big $$.

I live by doing things properly first time. Otherwise, it's not worth doing.

 

[rh1]

This goes against my very nature and I wouldn't be able to live with myself knowing I half assed it.

I'm fortunate enough to have enough skill to do this myself thanks to my trade background and prior work experiences. Plumbing team coming in to re plumb a house is big $$.

I live by doing things properly first time. Otherwise, it's not worth doing.

I bought the house like this, and there is only a few pipes in walls left that needs to be replaced. Insurance paid for it. Had I done it, it would have cost me more.

 

[RandomRando]

I bought the house like this, and there is only a few pipes in walls left that needs to be replaced. Insurance paid for it. Had I done it, it would have cost me more.

I'm interested in knowing more, lol.

I assume that my insurance would laugh at me if I had a pipe leak due to maintenance or some **** not being done if they see the pipes in their current state.

Still won't deliberately buy class 0 pipes lol. How was this determined in you case? Surface mount or chased?

I opened my wall up a little more, and I have space for lagging, so I'll likely get some holderbats, mount the pipe and lag it, before closing.

All these years on the family home in kzn it never occurred to me to do this on chased pipework. Only on surface mount. Granted, there haven't been any issues but ya. Unnecessary risks and all that

 

[rh1]

I'm interested in knowing more, lol.

I assume that my insurance would laugh at me if I had a pipe leak due to maintenance or some **** not being done if they see the pipes in their current state.

Still won't deliberately buy class 0 pipes lol. How was this determined in you case? Surface mount or chased?

I opened my wall up a little more, and I have space for lagging, so I'll likely get some holderbats, mount the pipe and lag it, before closing.

All these years on the family home in kzn it never occurred to me to do this on chased pipework. Only on surface mount. Granted, there haven't been any issues but ya. Unnecessary risks and all that

First pipe burst, five months after moving in. It was in the main bathroom. Plumbers opened the walls up to replace and insurance paid minus the excess. The next pipe burst was the kitchen, same process including replacement of kitchen cabinets. Then there was the geyser burst. They replaced quite a bit of the old pipes with that. So only a few left.

Its not lack of maintainence. I bought the house like that. Only found out after the first pipe burst.

 

[RandomRando]

First pipe burst, five months after moving in. It was in the main bathroom. Plumbers opened the walls up to replace and insurance paid minus the excess. The next pipe burst was the kitchen, same process including replacement of kitchen cabinets. Then there was the geyser burst. They replaced quite a bit of the old pipes with that. So only a few left.

Its not lack of maintainence. I bought the house like that. Only found out after the first pipe burst.

Interesting.

Essentially, my whole house needs new pipes, save for the ensuite bath thats 15mm copper. I've today stripped the ensuite shower walls and vanity and see that in this room, the main cold water pipe to the vanity is rotten, but hot water seems OK.

Everything else is galvanised, with seemingly obvious rotten sections raising the tiles & cracking plaster. In the roof, the hot water pipe from the geyser, after the tee, has rust patches on it at varying intervals. This is how I knew I'd need to redo the plumbing at some stage, but didn't know how bad it was in the walls. It is also why I thought insurance would fob me off. Seeing it visible like that surely would fall under maintenance work to replace/ fix the pipe. A hidden wall leak is kind of understandable as you can't see the condition of the pipe.

I figured there was no way insurance would pay out for an entire refit and if they did, it would likely be in stages and be surface mount. This only solves the plumbing side of things and not the plaster and tiling issue from the pipe rot.

My plan has changed now entirely, from just hot water pipe to all pipes and redoing the entire system. Need to switch over to a temp plumbing system to give me freedom to chase walls open and remove the rotting galv. without springing a leak while working.

Will be using unitwist fittings and pipe for this temp solution.

Wife is not amused lol.