Replacing old pipes


P

pmr

I'm sure the water pipes are full of crud and need to be replaced.
The bottom line question is how can I discover the route of our old
existing pipes without opening the walls? I want to know what I am
likely facing in terms of mess and disruption and expense before I
start calling plumbing contractors for estimates.

More detail: In our 1915 house all the pipes inside the walls are at
least 40 years old, maybe older. They are definitely not copper; I
hope they are not lead. I can see where the pipes go up from the
basement. They go first to the bathroom on the second floor then
across somehow to the tub and sink and toilet (where the water
pressure is adequate, but not great) and then down to the kitchen sink
on the first floor (where the cold water pressure is adequate, but the
hot water pressure is little better than a trickle). The pipes
necessarily have to make several turns along the way. The walls are
lath and plaster. There are baseboards, other woodwork and ceramic
tiles. Is there some device I can buy or rent to try to determine the
exact pipe path to see what might have to be torn out?

Alternatively I am considering just capping off the existing pipes and
finding a different route. The simplest way would put part of the
pipes outside. Would this be a problem? It freezes here in San
Francisco about two nights every 10 years or so.

Useful suggestions on how to proceed will be appreciated.

Paul in San Francisco
 
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B

bill a

It sounds like you have galvanized steel water lines, and they likely are
closed up.
Running pipe through existing walls requires a ton of technique that's
pretty much not describable
to a newbie. If you shop around for the right guy (probably an old guy),
it may not cost as much as you think
to run new lines.
Bill
 
S

Speedy Jim

bill said:
It sounds like you have galvanized steel water lines, and they likely
are closed up.
Running pipe through existing walls requires a ton of technique that's
pretty much not describable
to a newbie. If you shop around for the right guy (probably an old
guy), it may not cost as much as you think
to run new lines.
Bill
<SNIP>
Agreeing with Bill (and others).

Hold a magnet to the pipe. Sticks- you have galv iron pipe.
Typical life is 40 years. <bg>

Re-piping a 1915 house takes lots of skills so you don't wind
up with a real hack job.
A pro who has done this before will have in his head a map of
where things can go.
Just as one example: frequently, a baseboard can be removed
in a hallway outside the bath, giving access to the joist spaces.
May not apply to your house- just an example.

Ask neighbors with similar vintage house what they have/who they used.

I don't know about outside piping in SF (you'd have to ask) but
it would be prohibited in most cities.

For re-piping, soft copper tubing can be used; it will pull thru tight
spaces where rigid pipe won't. Also, if allowed, PEX plastic tubing
is a very good choice.

One final note: In 1915, it was *very* common for the Cold water
piping to be used as a grounding means for switch boxes in places
like bath/kitchen, etc. **IF** your house used that scheme,
abandoning the old piping will break all those grounds. Just a fine
point to have considered by the tradesmen.

Look for a contractor who carries liability insurance and who can get
permits in SF.

Jim
 
P

Paul M

Thanks. I never had any intention of doing the work myself. I just
wanted to start by finding out the routing of the existing pipes so I
could anticipate how much disruption and expense an experienced
contractor would likely cause.

Paul in San Francisco
 
P

pmr

Speedy said:
Agreeing with Bill (and others).

Hold a magnet to the pipe. Sticks- you have galv iron pipe.
Typical life is 40 years. <bg>

Re-piping a 1915 house takes lots of skills so you don't wind
up with a real hack job.
A pro who has done this before will have in his head a map of
where things can go.
Just as one example: frequently, a baseboard can be removed
in a hallway outside the bath, giving access to the joist spaces.
May not apply to your house- just an example.
Thanks for your good suggestions, most closely answering the concerns
I had.

Paul in San Francisco
 
I

Inspector D

Speedy said:
<SNIP>
Agreeing with Bill (and others).

Hold a magnet to the pipe. Sticks- you have galv iron pipe.
Typical life is 40 years. <bg>

Re-piping a 1915 house takes lots of skills so you don't wind
up with a real hack job.
A pro who has done this before will have in his head a map of
where things can go.
Just as one example: frequently, a baseboard can be removed
in a hallway outside the bath, giving access to the joist spaces.
May not apply to your house- just an example.

Ask neighbors with similar vintage house what they have/who they used.

I don't know about outside piping in SF (you'd have to ask) but
it would be prohibited in most cities.

For re-piping, soft copper tubing can be used; it will pull thru tight
spaces where rigid pipe won't. Also, if allowed, PEX plastic tubing
is a very good choice.

One final note: In 1915, it was *very* common for the Cold water
piping to be used as a grounding means for switch boxes in places
like bath/kitchen, etc. **IF** your house used that scheme,
abandoning the old piping will break all those grounds. Just a fine
point to have considered by the tradesmen.

Look for a contractor who carries liability insurance and who can get
permits in SF.

Jim
Go with a "repiping specialist" in your area. They are very fast and
know all the tricks. They will also patch your walls when done. Their
prices are likely to be cheaper than a regular plumber.
I ran a copper repiping company here in SoCal for 10 years. I know
there are people up there too that do the same thing.

A quality repipe should use type "L" copper, not "M". Little or no
"soft copper", that's for hacks who don't know what they are doing.
Most if not all of the old galvanized should be removed. Contact
between galvanized and copper will eat up the copper. Plastic or "PEX"
pipe may be allowed in your area but probably not. It would be
acceptable if legal.

Good Luck

PS, typical price for a two bath house including the main from the
street, new tub/shower valves (replace these now or open walls later
when you cant find parts for the 40 year old ones you have now.) and
possibly a new water heater should be around $5000 give or take. Get
estimates and BE SURE TO USE A LICENSED PLUMBING CONTRACTOR, GET PERMITS
AND HAVE IT INSPECTED BY THE CITY. If you don't, you are asking for
trouble.
 
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J

jackofall

Shut off your water main valve.
On that slow hot water faucet, remove the supply tube under the sink.
Then remove the shutoff valve. If the pipe behind this valve is
clogged with rust, you got plugged pipes. However it could just be
that last short nipple that is clogged. Try to open it with a
screwdriver, by forcing it into the rust If you do this, you need to
flush out that pipe by holding a bucket under the pipe and having
someone SLOWLY turn on the main until the crud comes out, and shut off
the water immediately after. Now, replace both the shutoff valve and
supply tube. (whether or not you had to scrape out that pipe). 9 out
of 10 times, this will solve the slow faucet. If not, take the supply
tube off the faucet end, again, stick it in a bucket and turn on the
water. If you have lots of pressure, you could have a bad faucet on
the sink, which simply means to replace the faucet. If its still slow
from that supply tube, you got clogged pipes and need to get yourself
a contractor.

What I suggested is pretty basic if you know how to use hand tools.
However, DO NOT break off that nipple in the wall if its stubborn, or
you'll be opening the wall at that point.

I was a plumber for 8 years, and I dealt with this sort of thing
thousands of time. This is how I checked.

PS. If those galv. pipes are original from 1915, and have not clogged
up till now, you do not have a high mineral content in your water.That
would tell me that the whole system is unlikely clogged. It usually
clogs at shutoff valves/supply tubes, and the pipes directly above the
water heater.

DO NOT run pipes outdoors if there is ANY possibility of freezing,
unless you want to replace them again after each freeze. or run all
sorts of heat tape.

(e-mail address removed)

George
 
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Hey George, our home was built in '68 and, of course we're dealing with galvanized pipes. I'm no plumber by any means but our kitchen sink has slowed to nill. When I replaced the water heater shortly after moving here I found scale buildup at the connection to the house. This was about 45 years ago. I suspect that while the cold water is fine the hot water at that one fixture is zip, I may be dealing with rust or scale. I'm going to try your method and see if I can get the ball rolling. I appreciate the detail you've pointed out. My poor wife is having fits over this.
Ratz the darned supply line is behind a plywood panel, guess I'll have to cut the panel dangit.
 
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