I am racking my brain over this, and I'm wondering if anyone else has been in this situation.

I have a water supply line for the small rental building which is on a slab, its a galvanized pipe. Its an older building, 1930 but solidly built.

A new shutoff valve for the building was put in about 12 years ago, above the original one which was not leaking, but had a broken handle. The new valve is a brass 90'. All well and good.

Except they used black iron fittings when they put the valve in, and should not have. The plumber who did it is gone.

Now the pipe is rusting, and has some sweating below the valve. There is a 2" section of pipe between the fittings that is now all covered in rust, and has standing sweat on it. Its not dripping yet, but I don't like it.

I've had some people say just seal it with silicone and leave it, but I want to change it out and have it done correctly because I fear galvanic corrosion, which in theory could be eating away at the pipe threads and lead to a break and flooding the apartments one day.

Here's where I talked to a number of plumbers and got estimates to fix this.

Some said they could do it no problem- the fittings are only 12 years old, and the slab has been tested then and was fine. If its galvanic corrosion, then the 2" section of pipe is the 'sacrifice', the spot that is taking the rust. They can take that out, we swap fittings with the right metal, and problem is solved.

But some plumbers talked about the pipe breaking off in the slab.

This would be a huge, expensive job, and they would stand to make a ton of money off it. Involving chiseling down into the concrete, using a borer, and on.

So what in the world is the incentive, for the plumber not to just break the pipe when changing the fittings, so they can land the big, lucrative job?

Whats even worse, is that plumbers have long wait lists in my town. I've been trying to call around just to get some other estimates from other plumbing companies IF the one I hire breaks the pipe off in the slab, just so I can at least not be stuck paying whatever they want to charge after getting their estimate and have options.

But all of them are scheduled out a week or more.

As a landlord, you're basically stuck with a building with no water, angry tenants refusing to pay rent, and no choice but to go with the company you hired, time and materials and pay whatever price they charge, or wait weeks for someone else.

How do people manage this? It seems like a complete trap, and for the life of me I can't see what I can do to avoid getting hit with a massive bill if they choose to break the pipe. I even called a plumber yesterday and said "what if?" and they just replied, we charge as much as it takes... we can't tell you until it happens..... and no your insurance won't pay for it AND we don't guarantee it won't leak afterwards.

WOW.

It looks like Im dan med if I leave this, and I'm dan med if I try and fix it. I certainly don't want to put a band aid on a water supply line, but I will be completely at the mercy of whoever I hire, basically a blank check.

I'm not sure what you do in this situation?

Black Iron Pipe should NOT be used for water! Iron rusts, galvanized does not! If oxygen get into the line, during city maintenance or a turn off, your black pipes will start to rust.

After all that,

thanks for reminding me why I did 97.6% of the work, myself.

Have you been using this plumber for a while or is he new to you? Not being able to trust them is a red flag for sure.

I would leave it until you find someone who seems a little more reputable. At least get a worse case scenario price.

Having galvanized in the slab is a time bomb as well to me. I know a guy that ran 1/2" pex inside 3/4" CPVC because of leaks and trouble replacing it all. Maybe that could work. They won't have the volume tho. I had one place that was all plumbed in with new 1/2" pex. Everything worked but I always wondered about time to fill a tub and such.

How far is the stub out coming in from the slab? I like the idea of running new lines from the meter to the building. If it is close you could possibly have it dug under the slab, core drilled out and the new pipe brought in.

A reputable plumber will want to do it fast and right. If you go with the cheapest bid, expect to pay for it.

I’d get a few quotes and ask them specifically what the plan is, as well as what precautions they’ll be taking g to avoid breaking the pipe.

Make sure that they don’t send an apprentice out to do the job. That was common when I was in the field as an electrician.

Is this an occupied unit? Why would they not have water?

If it is occupied, just replace the piece with the valve, for now. It should only take maybe 1/2 hour - no inconvenience for tenants.

BUT, prepare to re-plumb it when it is vacant. Galvanized pipe from the 30's is just a sneeze away from falling apart everywhere. Abandon the old pipes in the slab & in the ground, and maybe even in the walls if you don't need to open it all up.

Every house I've ever purchased has had galvanized (or nothing, because the copper thieves stripped it).

My plumber is local, so he's very used to working with brittle, crumbling galvanized. I know he'll be very careful, and he's worked some miracles. He's advised me at times NOT to replace an existing section, because of the risk of it breaking apart further and further down.

Would you rather fix it at your convenience or as an emergency? You know you have to do it, it's just a matter of when.

You have a bigger problem brewing. I guarantee that nearly 100 year old galvanized pipes are rusting from the inside out. It's just a matter of time before they either rust shut or rust through. Either way you are going to be replacing the entire fresh water system.

Galvanized pipes do not contain lead as a primary material, but they can absorb and retain lead from other sources, leading to potential contamination in drinking water. Studies have shown that galvanized steel pipes coated with zinc that contains lead can be a significant source of lead contamination

Additionally, lead particles can attach to the surface of galvanized pipes, which may elevate lead levels in drinking water over time. Corrosion in these pipes can also contribute to lead accumulation in waterlines.