1930s house with galvanized for cold and copper for the hot?

luketheplumber

This one has had me stumped for years now. The house that I live and grew up in was built in 1935. The plumbing is mostly copper along with some original galvanized still in use on the cold lines going up the the 2nd floor bathrooms. I can tell due the the difference in the fittings that sometime in the past, someone replaced all the galvanized in the basement with copper.
Anyways my question is, why would a plumber choose to plumb a new house with copper for the hot and galvanized for the cold instead of just going with one type of pipe all the way?

ChrisJ

Any chance it only had cold water until the 50s when copper became really popular?

Jamie Hall

Are you sure it was originally done that way? It wasn't at all uncommon to replace accessible galvanized lines -- with their rust and reduced flow -- with copper where it wasn't that hard to get at.

Robert_25

When I ripped the galvanized piping out of my own house, most of it was being used for cold water - but there was a few feet that was used for hot water. The galvanized piping used for hot water had a large amount of internal corrosion/deposits compared the cold water piping. Perhaps the same thing happened in your house, and only the piping with restricted flow was replaced.

mattmia2

I'm sure the hot rotted out and was replaced. Heat makes the reaction go a lot faster. The hot will clog and leak while the cold will be more or less clear. That is what I did in my mom's house. The hot started leaking in the early 90's(the house was built in 1957), a piece or 2 was replaced, i replaced all of the hot in the late 90's, most of the cold is still galvanized and the flow is still ok.

mattmia2

Of course the question remains why was someone cutting and threading galvanized in 1957, the increased labor couldn't have offset the cost difference between steel and copper.

EBEBRATT-Ed

If the house was built in 1935 it could well be galvanized. Copper was just getting started around that time. Chances are some of the galvanized failed and it was replaced with copper

mattmia2

I think there is something about galvanizing doesn't work at elevated temps too but I don't know the chemistry of it. That is sort of a @Larry Weingarten question.

ChrisJ

mattmia2 said:

I think there is something about galvanizing doesn't work at elevated temps too but I don't know the chemistry of it. That is sort of a @Larry Weingarten question.

Seems to work fine with anode rods in water heaters

luketheplumber

Both pipes look like they were there from the beginning. Looks like someone replaced all the easily accessible galvanized with copper in the basement and crawlspace but left the runs going up the walls. If yall want, I have no problem crawling and getting a few pictures of the galvanized as well as both the new and old copper fittings.

mattmia2

ChrisJ said:

mattmia2 said:

I think there is something about galvanizing doesn't work at elevated temps too but I don't know the chemistry of it. That is sort of a @Larry Weingarten question.

Seems to work fine with anode rods in water heaters

what water heaters are galvanized? modern steel water heaters are porcelain with a magnesium anode.

Larry Weingarten

Hi, Pure zinc anodes aren't made for water heaters because at around 140F, things turn around and the steel begins to rust away to protect the zinc. At lower temps, zinc protects steel. Also, a rule of thumb is that for every 20F rise in temp, chemical reactions double in speed. That would help explain why hot galvanized steel doesn't last as long as the cold side piping.

I don't know if it would help, but older fittings for copper pipe had holes drilled in the side of them so you could insert solder there. When copper piping was new, plumbers didn't believe in capillary action to pull solder into the joint. If we could see some of the fittings, it might help us to date when the copper work was or wasn't done. Here is a photo of one of those old fittings.

Yours, Larry

ChrisJ

Larry Weingarten said:

Hi, Pure zinc anodes aren't made for water heaters because at around 140F, things turn around and the steel begins to rust away to protect the zinc. At lower temps, zinc protects steel. Also, a rule of thumb is that for every 20F rise in temp, chemical reactions double in speed. That would help explain why hot galvanized steel doesn't last as long as the cold side piping. I don't know if it would help, but older fittings for copper pipe had holes drilled in the side of them so you could insert solder there. When copper piping was new, plumbers didn't believe in capillary action to pull solder into the joint. If we could see some of the fittings, it might help us to date when the copper work was or wasn't done. Here is a photo of one of those old fittings. Yours, Larry

Interesting.

When were those fittings being used Larry?

ChrisJ

I'm a bit confused by the comments regarding temperature and zinc protecting steel.

@mattmia2 I was talking about using anode rods in general but @Larry Weingarten everything I can find about galvanized steel shows 392f as being the upper limit and even then there's peeling issues not issues with reversals and the steel protecting the zinc?

Also all single wall smoke pipe is galvanized pipe, no?  And we always see galvanized or zinc plated parts on boilers that get very hot.

mattmia2

Piping is filled with water that can carry ions of metal away, sheet metal jackets and ducting and such are only subject to oxidation from the air combining with the surface and form an oxide layer that reduces further oxidization. They are different processes.

I'd be interested in the chemistry of the galvanizing reversing around 140 f. I wonder if it truly reverses or if the reaction just proceeds so quickly that the zinc dissolves and leaves the iron unprotected.

ChrisJ

mattmia2 said:

Piping is filled with water that can carry ions of metal away, sheet metal jackets and ducting and such are only subject to oxidation from the air combining with the surface and form an oxide layer that reduces further oxidization. They are different processes.

I'd be interested in the chemistry of the galvanizing reversing around 140 f. I wonder if it truly reverses or if the reaction just proceeds so quickly that the zinc dissolves and leaves the iron unprotected.

I'm always open to learning something new, but not a single thing shows any such behavior like zinc becoming more noble than steel at a certain temperature exists. That I could find anyway....

That doesn't mean it's not true, but so far it seems that way to me.

Larry Weingarten

Hi, I don't remember where I learned this, but here's a link to an article than at least acknowledges the reality of zinc becoming noble to steel. https://www.sciencedirect.com/science/article/abs/pii/S0010938X74800429?msclkid=59787889c1a011ec929d40b1770eeb36 Clearly more snooping around on the internet is needed!

Yours, Larry

luketheplumber

@Larry Weingarten Those are the exact type of fittings used on the original copper lines.

luketheplumber

Risers to 2nd floor bathroom. I know that the galvanized is starting to drip and needs to be replaced, I'm going to do it soon.Old and new copper fittings.Here's a closeup of the original copper fittings.This riser was abandoned and replaced with PEX many years ago.

EBEBRATT-Ed

@Larry Weingarten & @luketheplumber I have seen those old fittings a few times. In fact, I had some that went into the scrap pile.

Luke, hard to read the writing on the tubing but 1 piece looks like type "M" although it's hard to read

mattmia2

All of those sort of like like they were crammed in as a retrofit.

Larry Weingarten

Hi @ChrisJ , All I know is these fittings were used in the early thirties, so this fits nicely with @luketheplumber 's house being built in 1935. I'm guessing they are Mueller Brass. Don't know if they have a history someplace that could verify the age of these fittings.

Yours, Larry

ChrisJ

Larry Weingarten said:

Hi @ChrisJ , All I know is these fittings were used in the early thirties, so this fits nicely with @luketheplumber 's house being built in 1935. I'm guessing they are Mueller Brass. Don't know if they have a history someplace that could verify the age of these fittings. Yours, Larry

I'm almost positive I removed a fitting like that from my bathroom but now I can't remember.  Most of what I cut out was 1950s stuff.

I think one of those was a section of pipe that went from 1/2" to 3/4 for two feet and back to 1/2 which really made me think for a while.   That and the cut off section of lead drain pipe that almost fell on my head.

Old houses......
They're fun sometimes.

mattmia2

The hot water may have been added sometime after it was built. Automatic water heaters barely existed in 1935 and I don't think any form of water heater was super common. My grandparents said their first house had a coal water heater and though they bought it probably around 1940 was probably built in the 30's sometime.

luketheplumber

My neighbors houses which were designed by the same architect, built around the same time and probably built by the same builder are mostly copper with copper pipes the same fittings. So I'm pretty confident that they are original.
The original bathtub was manufactured in 1935, confirming my house was built around 1935 or 1936 if that matters.

ChrisJ

luketheplumber said:

My neighbors houses which were designed by the same architect, built around the same time and probably built by the same builder are mostly copper with copper pipes the same fittings. So I'm pretty confident that they are original. The original bathtub was manufactured in 1935, confirming my house was built around 1935 or 1936 if that matters.

From what I could tell my original bathroom which was added in 1910 had two 1/2" galvanized lines going to where I think the bathtub used to be before the steam system was added to the house.

I don't know what they used as a water heater at the time but I did find an add on water heater for a wood stove thrown in the crawl space.   I guess they could've lit a wood fire in the kitchen to go up and have a bath?


I never even put any thought into it until this thread. 

ChrisJ

@luketheplumber this is the thing I found.
I think @Larry Weingarten had told me what it was.

Larry Weingarten

Hi, That looks like something that would go in the firebox of the kitchen stove. Nearby would be an uninsulated tank and gravity flow would heat the tank when you had a fire going in the stove. I had an old-timer tell me that when it was hot "down to here", as he was putting his hand on the side of the tank, he knew he had enough for a bath. There were no safeties or automatic controls at all. You had to pay attention!

Yours, Larry

EBEBRATT-Ed

Don't forget the advent of WW2. During the war years (so I have been told) everything was in short supply with pipe and fittings on the top of that list.

This caused a lot of scrap yard scrounging and mixing and matching to make a job work even slightly before and after the war.

My uncle and some relatives worked at Gilbert & Barker when their factory was in Springfield. G & B moved south in the 60s.

There are still some Gilbert & Barker boilers and oil burners around. You may know them as "Gilbarco" they make gas station pumps and other petroleum stuff.

Anyhow, my uncle and his brothers bought an old farmhouse 1800s vintage in the 40s and installed (or had installed) a Gilbert & Barker boiler and burner. I suspect they did it themselves

I replaced it in the late 70s or early 80s. It was all installed with copper fittings. Some were long radius refrigeration fittings; some were brass fittings; some were medium radius elbows, a few standard elbows and a bunch of street elbows with couplings added to make an elbow. it was a little funny looking.

So, they used whatever they could get

JakeCK

EBEBRATT-Ed said:

Don't forget the advent of WW2. During the war years (so I have been told) everything was in short supply with pipe and fittings on the top of that list.

Sounds familiar.

And is scary as hell too.

luketheplumber

I'm not sure how my house got hot water originally since it was built with a warm air coal furnace. I don't think the house even had gas until 2002. Was there any kind of side arm heater back in the day for hot water that could be put on a furnace?

mattmia2

luketheplumber said:

I'm not sure how my house got hot water originally since it was built with a warm air coal furnace. I don't think the house even had gas until 2002. Was there any kind of side arm heater back in the day for hot water that could be put on a furnace?

There very definitely were coal fired tank type water heaters.

Now that I think about it i wonder of my house had hot water before 1950 when it got municipal water and gas. There are remnents of a clawfoot tub where the modern tub is that I think was installed in 1950(the modern style tub). i wonder if the clawfoot tub had hot water. I think there are some holes in the subfloor for the supply piping, I'll have to look more closely sometime. The hot water was all copper when I bought the house. i assumed it had been replaced, but maybe it was installed in 1950. The house was built in 1924. The toilet is dated like 1934. I have heard from neighbors that there was a neighbor that bough their house in the 40's and it had an outhouse when they bought it so I think that 1934 was when it got indoor plumbing.

ChrisJ

mattmia2 said:

I'm not sure how my house got hot water originally since it was built with a warm air coal furnace. I don't think the house even had gas until 2002. Was there any kind of side arm heater back in the day for hot water that could be put on a furnace?

There very definitely were coal fired tank type water heaters. Now that I think about it i wonder of my house had hot water before 1950 when it got municipal water and gas. There are remnents of a clawfoot tub where the modern tub is that I think was installed in 1950(the modern style tub). i wonder if the clawfoot tub had hot water. I think there are some holes in the subfloor for the supply piping, I'll have to look more closely sometime. The hot water was all copper when I bought the house. i assumed it had been replaced, but maybe it was installed in 1950. The house was built in 1924. The toilet is dated like 1934. I have heard from neighbors that there was a neighbor that bough their house in the 40's and it had an outhouse when they bought it so I think that 1934 was when it got indoor plumbing.

There's a lot of stuff we just automatically assume is normal and never question it.

For example I'm almost positive my kitchen had one of these up until 1881 when the city water went in.  The stone cistern is still there.

mattmia2

When I lived downtown i lived in an apartment cut up out of an old house that was built in 1910. It had an old well for potable water and a cistern in the back yard that collected rainwater for nonpotable use. There were still pipes in to the basement from the cistern and the cistern was still there but filled in. It had a big stone cover on it.

Jamie Hall

Somewhat slightly off topic but not. Those risers going up the walls. I would seriously consider using PEX (either B or A, depending on your connecting preference) when replacing them. At least in the places I care for, getting a copper line up a chase can be a bit of a headache...

luketheplumber

@Jamie Hall I will definitely be putting back in some type of PEX, preferably Uponor. Copper is at like 30 dollars a stick here.