Low flow on some cold water lines.

Hello Everyone,

I just bought a house recently that needs a lot of remodeling work. On the plumbing side I was hoping someone on this forum can help me identify what my problem may be. I am seeing poor water flow on 3 out of 7 cold water outlets.

This is a small house with one bathroom (tub, sink and toilet), kitchen (1 sink), detached utility/laundry room and two outdoor hose bibs. The hot water flow in the house is fine. The cold water flow on the two outside faucets, the laundry room, and the tub are all good. The cold water flow on the bathroom sink, toilet and kitchen sink are all very poor.

The house was built in 1951. This house is in Texas and all the water lines are run through the attic. Due to the shallow pitch of the roof, I have not been able to get up into it, so my observations are from what I can see with a flashlight through the attic access. It has galvanized pipe for all the cold water lines and its using black iron pipe on the hot water lines. It looks like the the hot water lines have been done at a later time and it also appears that the previous hot water lines (galvanized) are still laying in the attic. If not, then I can't figure out why there is so much pipe. Also, the water supply to the house is on the opposite side of all the fixtures, so there is a long run going through the attic that has a couple of T's running off it.

It appears that the lines in question are part of seperate run of pipe and my first thought was that the pipe had corroded internally. What puzzles me is why the rest of the cold water lines would not be affected. Also, this house has set empty for nearly two years and only recently had the water turned back on.

Any ideas on what the problem may be and how I can test for it would be appreciated.

I'm going to stick my neck out and say the previous owner got either cheap or lazy, and just replaced the hot side of your water lines. I wish I would have saved a piece of the galvanized pipe taken from my house last November when I repiped in copper. It was a 3/4" inch pipe, and it would have been impossible to insert a pencil into it due to the rust inside.

Because you say that some of the cold water pipes seem to flow properly, I would guess that the closer to the source (water meter), the better the flow, and this is the routing of your pipes.

I have repaired 30-40 feet of rotten galvanized pipe for a customer once, but I told him there will be no guarantees and recommended he fully replace all of his pipes. Since he was going to get married and remodel his house in the next year, he opted for the cheap solution. The reason I mention this is because you might consider doing the same thing, which might last for a few years, and relatively inexpensive.

havasu said:

I'm going to stick my neck out and say the previous owner got either cheap or lazy, and just replaced the hot side of your water lines. I wish I would have saved a piece of the galvanized pipe taken from my house last November when I repiped in copper. It was a 3/4" inch pipe, and it would have been impossible to insert a pencil into it due to the rust inside.

Because you say that some of the cold water pipes seem to flow properly, I would guess that the closer to the source (water meter), the better the flow, and this is the routing of your pipes.

I have repaired 30-40 feet of rotten galvanized pipe for a customer once, but I told him there will be no guarantees and recommended he fully replace all of his pipes. Since he was going to get married and remodel his house in the next year, he opted for the cheap solution. The reason I mention this is because you might consider doing the same thing, which might last for a few years, and relatively inexpensive.

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Thanks for the response Havasu, I suspect you are right. When I bought the house I expected to have the lines replaced, just wanted to be sure that was the problem before going through the expense. This is an investment property for me that I plan on selling once the remodel is finished.

I'm having a plumber stop by this afternoon to give me his thoughts.

I believe you are making a good call. Good luck, and let us know what they say, as this may help someone else in the future!

Plumber came out yesterday afternoon. Turns out there was just build up in the flex lines on the two sinks and the fill valve and flex line on the toilet. Once we replaced the flex lines, we had good flow.

Good news, saved me a couple grand.

That's great news! Thanks for letting us know the outcome.