Hello,
I'd like to know what is the best size pipe for best pressure in home? I want to put new pipe in my cellar and 1st floor. My house has mostly 1/2" copper pipe. Should I go up to 1" to get better pressure? Also should I use the newer plastic type pipe. I think it's PVC pipe. Thanks

It is not pressure you are after, it is volume. By changing your main supply lines to 3/4" copper and leaving the individual branches as 1/2, you will have good volume and not have nearly the pressure drop when multiple fixtures are in use.
Good Luck

go to google and put in "pressure drop". lots of hits. for example--
[www.engineersedge.com]

In general, remember that you can never increase the pressure along a run of pipe ( without pumps) but you can try to minimize the loss. For a given flow ( gallons per minute) a larger pipe will have lower velocity of water, which is a good thing, and less pressure loss per foot of pipe.

In general, not knowing anything about your number of rooms, etc. or the length of runs, it would not be unusual to have a 1" supply line up to the house from a 5/8 or 3/4 meter; then 3/4 main runs through the house, with 1/2 feeders to individual fixtures. This is a pretty rough explanation. You should have a plumber look at it.

My house is a Cape Cod my runs are not even 30ft. I have a subm 1/2hp aeromotor then it goes into a Amtrol press tank then into my w/softener. I talked with a plumber and he said to go at least 3/4" dia and it should be good. Should I just go 3/4" like he said or should I go 1"?

I also hate my garden hose pressure should I just go 1" with that and go 3/4" thru rest of house. I'm going to put a inline filter in just before the w/softener. When you say only use larger pipe until you get to fawcett, where is the cut-off? I'm guessing you mean where you put in the valve to connect to flex hose for fawcetts, right? Or do you start using 1/2" copp pipe a couple feet before that?

I'd still like to know about plastic pipe instead of copper. Thanks



Post Edited

How many fixtures do you have? I would use a 1" main. I would carry 1" to the risers for the 2nd floor, or the water heater, whichever is first. 3/4" should be good for the hot main. I run all 3/4" except to the last fixture, then it's 1/2." I would run 3/4" to the sillcock, then within a few feet drop it to 1/2."


Peace out,

Kordts

The i.d. of plastic pipe reduces its effective size to the next lower copper tubing size, so 3/4" plastic is almost equivalent to 1/2" copper and forget about the "lower coefficient of friction" plastic installers talk about so they don't have to increase the plastic to the next larger size. "Bigger is better" only works until your velocity is at a maximum and friction loss is at a minimum. The water volume at your hose faucet is ultimately determined by the size of the opening in the valve's seat which is usually about 3/8" diameter, so 3/4" tubing would normally be adequate unless you had to run 150' or so to the faucet.

I am running 12" water mains right now. Every house we run by, we leave a 1" corp, the city is going to run the service to the house later. We had a running fight with a 1" copper service that our ditch went under, we hit it, and had to repair it. Then after we turned the corner, it was in our ditch. We hit it again when it turned to go to the house. It is about 3-400 foot of 1" and then the last 50 foot is 3/4." I bet they will freak when the city abandons the old service and runs the new 1" service off the 12" main.


Peace out,

Kordts

The house isn't that big 1-1/2 story 28ft X 32ft. I have 1 bathroom with bath, toilet and sink. And kitchen has 1 sink and a dishwasher. I have 2 outside spickets. I have an ice maker for fridge that connects to waterline but that shouldn't matter.

All this is on the first floor. So from what is being said here I'm probably ok with just 3/4" copper pipe, right? Do I use 1/2" pipe a couple feet before getting to any faucet including outside spickets? Or will the spicket boost the pressure for me?



Thanks



Post Edited

3/4" is fine. I would run 3/4" mains and branches. The only 1/2" is the last coupla feet between the branch and the fixture. Same for the sillcocks(spigots,) run 3/4" and within the the last coupla feet, reduce it to 1/2." By oversizing the pipe, you eliminate water hammer.


Peace out,

Kordts

I'll do that. Thanks