Household Water Pressure Issue

[Plumbs Away]

I've recently purchased a new-to-me home, built in 1968. The fresh water lines are galvanized from the street to the house and copper in the house. When I flush a toilet or use the clothes washer, the water pressure at any other location in the house is reduced to a trickle. I know some reduction is normal, but mine is little more than a steady drip. My parents live in the same subdivision, in a house built by the same contractor three years earlier, and they also have this issue. I grew up in their house and we did not have the problem to that extent years ago. Common sense tells me that it has something to do with the age of the plumbing. I found when I replaced all my leaky supply stops with quarter-turns that galvanized nipples were used from the copper pipe in the wall to the stops and they were corroded to the point of being almost totally closed, so I replaced the nipples with PVC when I replaced the supply stops. The water PSI in my neighborhood is around 95. Any suggestions as to how I can make the pressure more stable/consistent??? Thanks!

 

[Reach4]

I am not a pro. I think you would want to start with a couple of pressure gauges that can screw on to the hose bib, laundry water tap, or water heater. See if you can spot drops within the house. These are usually under $20, and many have a "lazy hand" to record the maximum or maybe minimum pressure that has been seen.

Will you need new bigger pipes inside, outside?

One partial answer would be to put in a pressure regulating valve on the incoming water, bringing the water pressure down to maybe 60 PSI to give some consistency. Those have some restriction. You would want one that minimizes that restriction. As part of the install, it would be a good time to put in a new ball valve (with the water at the street) and a tap for a water pressure gauges before and after the PRV.

The gauges would show if the trickle was caused by the house pipes.

If the problem is largely due to inside pipes, you may have very hard water. A softener would be worth considering if you have hard water. It would stop new deposits after the softener, and it would give nicer water to use.

 

[Sponsor]

 

[hj]

The galvanized main line is probably corroded shut, but PVC nipples for the fixture supply valves was the WORST choice you could have made. The threads can snap off after a few years. You should have used brass nipples instead.

 

[Cacher_Chick]

Start with a pressure gauge at the main line that enters the house to see whether the loss is in the supply line from the street or within the house. If it is inside the house, you might be well served by replacing the main horizontal supply lines first. If the piping is accessible, such as in a basement or crawl space, it is a lot less painful than if you are on a slab with piping below the floor.

 

[Plumbs Away]

The galvanized main line is probably corroded shut, but PVC nipples for the fixture supply valves was the WORST choice you could have made. The threads can snap off after a few years. You should have used brass nipples instead.

I actually did wonder about that. I'll change them to brass. Is it okay to use a PVC nipple to attach the bathtub spout?

That brings to mind another question: What is a suitable/better replacement for galvanized from the street to my house?

 

[Plumbs Away]

Start with a pressure gauge at the main line that enters the house to see whether the loss is in the supply line from the street or within the house. If it is inside the house, you might be well served by replacing the main horizontal supply lines first. If the piping is accessible, such as in a basement or crawl space, it is a lot less painful than if you are on a slab with piping below the floor.

I have a basement. How likely is build-up within copper lines?

 

[Reach4]

I have a basement. How likely is build-up within copper lines?

Seems unlikely, but it depends on your water. What is your hardness and pH? The water department will know.

 

[Craigpump]

Get rid of the galvanized pipes.

Don't use a PVC nipple for the tub spout.

 

[Plumbs Away]

Seems unlikely, but it depends on your water. What is your hardness and pH? The water department will know.

Thanks, Reach. I know the water's hard but I'll ask about the pH. Of course, they will likely have no idea what I'm talking about!

 

[Plumbs Away]

Get rid of the galvanized pipes.

Don't use a pvc nipple for the tub spout.

Should I replace the galvanized from the street to the house with copper? If not copper, what?

 

[Cwhyu2]

I would go with copper to replace the main.

 

[Reach4]

Should I replace the galvanized from the street to the house with copper? If not copper, what?

Ask your water department; they may have requirements. High pressure polyethylene or PEX would be good (I suspect better), and for sure a lot cheaper than 1-1/4 copper. There are techniques to allow the plastic pipe to expand and contract a bit with temperature.

It may be that cwhyu2 would not be allowed to use poly in his area, so he may not have much experience with that -- not that I have any.

 

[Terry]

Many older homes used the water service to ground the electrical box. Before and water service replacement, you should first take care of the grounding for the electrical.
Choices for a new water service would be
Copper
Poly
PVC
PEX
PEX is less than full size, so you may want to opt up a size for that.

To size a new line.
https://terrylove.com/watersize.htm

A two or three bath home needs 1"
A four bath should have 1-1/4"

 

[Cacher_Chick]

I would not jump to replace anything until a positive diagnosis has been made.
You could spend a fortune to replace the main line from the street and still have the same problem if there is a restriction in the house.

 

[Jadnashua]

FWIW, all public water utilities are required to perform frequent water tests, and they should be able to give you the results.

 

[Plumbs Away]

FWIW, all public water utilities are required to perform frequent water tests, and they should be able to give you the results.

They just might at that, although things are SO effing backward and antiquated here. Our latest big news in re our city water is that the addition of fluoride is being terminated. That being said, they should have some recent test results.