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Galvanized Steel to PEX

Updating home water lines from galvanized to PEX. The run from the water meter is going to remain 1/2" galv. While looking at the PEX pipe at home depot I noticed the the inside diameter of 1/2" pex is smaller than the1/2"  galv. Should I run 3/4" PEX to maintain the inside diameter or should I just run 1/2" PEX and stop worrying about it?

Re: Galvanized Steel to PEX

Pipe is sized by its inside diameter while tubing  is sized by its outside dianmeter. Personally I would go with 3/4" PEX.


Re: Galvanized Steel to PEX

The size of the pipe does not give pressure, the volume that can be pushed thru the pipe gives you pressure. I do not like anything plastic. It has not been proven enough. I know that it can easily leak, and it can make the water taste odd when left in the pipe too long. We had a mix of copper and galvanized steel. Way too small and the glavanized rusts from the inside. I suggest using a large diameter pipe to feed the house on the street side of the pressure regulator. This will give you the maximum flow that the city will give.

I have a 2" copper line feeding my house from the street(approx 200ft). I slid the copper pipe into a 4" schedule 80 PVC pipe, in case I needed to ever run new, I can do that very easily remove the 2" pipe, and slide another one in its place without having to dig up the yard. It goes into a large collections of filters, guages, softners, lights, manifolds and ball valves. The manifolds are 1.5" copper and the single pipes that feed only one room, or one section of a room is 1" copper. In each room, say a single bathroom. There is another manifold with valves for each half of each device. One manifold for the hot water and one for the cold water. Each half of each device is fed using 3/4" copper. The use of manifolds  allows the pressure to always remain the same, no matter what else is happening in the entire rest of the house. This also allows me to turn off a complete room, or if needed, turn off only one half of any one single device in that room. This way, I can turn off the cold water only to the sink if needed, while all the other devices still have normal water supply. Another thing I used were long sweep 90 degree elbows. This keeps the water flowing at the same rate and greatly improves flow over a short 90 degree elbow.


Handy Andy In Mt Airy NC

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