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Matt Fellman
03-11-2008, 07:50 PM
In case anyone's interested... here's a pic of some super corroded galvanzied supply plumbing out of a 1971 house. So, the next time a buyer asks... "why is the flow so bad?" .... give them this picture.

Rick Hurst
03-11-2008, 08:21 PM
Matt,

Its surprising that any water got throught that line.

Your picture reminded me of this one today of a dryer vent since were looking down things.

Jerry Peck
03-12-2008, 05:57 AM
galvanzied supply plumbing out of a 1971 house.

Isn't that an oxymoron? :)

Who, in 1971, would have used galvanized piping? I mean, sure, way back in the dark ages, say, the 1930s and maybe even into the 1950s ... but in 1971?

Rick Cantrell
03-12-2008, 08:49 AM
Jerry
In my area, on a house that age, it's not uncommon to see copper water lines in the wall, with galvanized nipples come out the wall.

Jerry Peck
03-12-2008, 12:42 PM
In my area, on a house that age, it's not uncommon to see copper water lines in the wall,

That would be expected.


with galvanized nipples come out the wall.

Why?

Why use galvanized for that? That would require a brass or bronze fitting between the copper and the galvanized.

Gunnar Alquist
03-12-2008, 04:29 PM
Galvanized nipples to copper tubing is what I have in my 1963 house. At least, what I have not yet replaced.

Rick Cantrell
03-13-2008, 05:09 AM
"Why use galvanized for that? That would require a brass or bronze fitting between the copper and the galvanized."

I can't answer that, could be the plumber had threaded shutoffs that needed to be used up.

imported_John Smith
03-13-2008, 04:15 PM
Was the ID of the pipe exposed, or did you disassemble some fittings to look at it?

imported_John Smith
03-13-2008, 04:18 PM
My personal home was built in the mid 70s and has galvanized piping throughout. It was very common in the Houston Area.

I have disassembled a joint or two (not due to leakage), and it was surprisingly free of calcium restriction. No leaks as of yet. I am on city water also.

Matt Fellman
03-13-2008, 07:09 PM
Was the ID of the pipe exposed, or did you disassemble some fittings to look at it?

The pic I posted was as I found it at the inspection. The supply plumbing had all be redone which is somewhat uncommon for a 1971 house. It seems that most people just live with the restriction of flow.

The variation in corrosion and subsequent restriction of flow has always intrigued me. As with anything I know there's a variation in materials which could account for some of it.

I have another theory that I've never heard anywhere but kind of just made up on my own: The process of galvanizing something usually consists of coating it with zinc. Thinking back to chemistry class, zinc is somewhat reactive with many other minerals. My theory is that the variation in minerals from different water results in a varying amount of corrosion on the inside of the pipes.

I've seen 100 year old houses on wells with flow like brand new plumbing and I've seen 25 year old pipes totally gummed up (kind of like the picture I posted). It's just hard to believe there is that much variation just because of the piping. I'm more inclined to think it's the water going through it.

Just a theory.... I'm no plumber (or chemist for that matter)....

BARRY ADAIR
03-14-2008, 07:32 AM
Here is what they have and what they are trying to convert too. Not real sure which is better :confused:

Jim Luttrall
03-14-2008, 08:32 AM
Barry, that is one scary mess.

Jack Feldmann
03-14-2008, 09:06 AM
It's very common to see galvanized nipples (connected to copper pipe)coming out of a wall. Why don't they use brass or bronze???? $$$$$$$

Sometimes, especially at a laundry connection, the copper is soldered to a brass fitting that has a nail flange and female threads for the nipple. I've seen those used a lot.

But then, we also see copper/galvanized connections all the time. I think the main reason people do it is they just don't carry brass nipples around (to save money), and think that no one is going to see it and complain. The second reason is that most of the dimwits that do repairs don't know they are not supposed to connect the two materials.
JF

BARRY ADAIR
03-14-2008, 02:55 PM
Barry, that is one scary mess.

Jim,
My friends don't call me "badair" for nothing

Dana Bostick
03-14-2008, 09:52 PM
From a Plumber's experience.....
Pre WWII galvanized was much better. When the war started, many materials got diverted to the war effort so zink was in short supply and the pipes got a thinner coating.
After the war the US was trying to rebuild Japan and was importing a lot of steel pipe from them that was really crap. Much of the early Japanese stuff was at first.

Also, Union vs. Non-Union has some play on newer jobs. 1970's on houses with Gal was probably Union work since it take a bigger crew to install gal vs copper. "Featherbedding" at work!

Out here in Cali, we have areas that got plumbed in Gal in the 80's because of Union work shops and all had to be repiped in 10 years due to massive failures of poor quality pipe.