[mholmen71]

My house has a 5/8 inch meter that comes into the house, then immediately out of the meter it goes down to 1/2 inch. The 1/2 inch line then goes from the front of the house to the very back (~30-35 feet), before it hits a T. One side of that T then continues and splits off more to the washing machine, water heater, kitchen sink and two full bathrooms. The other side of the initial T goes to an outdoor water faucet.

As you can imagine, if more than one faucet is on at one time there is a lack of water volume (flow?). This particularly affects the water volume for running sprinklers and affects the range of the sprinklers.

My thought is to replace the main line with 3/4 inch line from the water meter all the way back to that first T. Will this really be worth the effort and help with my water volume (flow?) at each faucet or am I looking at this incorrectly?

Thanks
Matt

PS. I probably have some of the terms wrong, if I do please correct me so I understand it correctly.

 

[Old Thomas]

3/4 has twice the volume of 1/2, so the answer is yes.

 

[dj3]

Smart move.
What kind of main pipe do you have now, and what will you replace it with?

 

[mholmen71]

Right now the main pipe to the back of the house is 1/2 copper.

After the T at the back of the house is a mix of older 1/2 copper and newer 1/2 pex (from when we moved the water heater and redid the bathroom).

I was debating on copper versus pex. Leaning towards the pex at the moment as I feel like it would be easier for me to do and make it look good. I can do sweat joints with copper (as done on previous repair) but they are not pretty.

I think doing pex with a crimp tool, will make it look better than copper and a bunch of shark bites.

Also considering adding a manifold at the back of the house close to where the T junction is now if I can do it without too much trouble. Main issue thought is just getting better flow throughout the house.

Thoughts?

 

[Old Thomas]

I use PEX and stainless pinch rings. In my house I ran 3/4 mains with takeoffs in 1/2 so no 1/2 serves more than 1 outlet. The exception is that I ran 1/2 hot to the upstairs bathroom because 1 person uses it at a time and I didn’t want to wait too long for hot water.

 

[mholmen71]

Just took a look at where everything is right now to try and figure out what I can do, and it looks like I can do 3/4 back to the original T, then take 3/4 out of one side of that T to continue the "MAIN" while 1/2 goes out the other side to the single faucet in that direction. If i follow a similar path for the 3/4 side of the T I believe I can get each first floor faucet onto its own 1/2 trunk. Second floor I am out of luck on for now as it is a single 1/2 pex line going up. The kitchen sink and the HW heater currently share the same 1/2 line so I might leave that as is.

Do either the HW heater or a boiler require copper into them or could they be PEX as well?

Tempted to leave the copper going in and just tap onto the new 3/4 pex with the same 1/2 inch copper.

 

[dj3]

"Do either the HW heater or a boiler require copper into them or could they be PEX as well?"
- You have to check with your building dept, it varies from place to place. In my city 3/4" copper has to be from the WH for at least 2'. The T&P drain pipe must be 3/4" copper TO THE OUTSIDE OF THE BUILDING.

 

[Old Thomas]

Here the materials connecting to the water heater can be any approved potable water material. And the T&P must be piped to within 6” of the floor or piped to a safe place with an air gap. It doesn’t have to go outside, most are in cellars.
We don’t have to strap water heaters, either. Not a “Whole lotta shakin goin on” here.

 

[mholmen71]

I use PEX and stainless pinch rings. In my house I ran 3/4 mains with takeoffs in 1/2 so no 1/2 serves more than 1 outlet. The exception is that I ran 1/2 hot to the upstairs bathroom because 1 person uses it at a time and I didn’t want to wait too long for hot water.

Do you know what your water flow and pressure are after you did this? What sized is the outlet at your meter?


My current setup looks like I have 5/8 inch inlet to the water meter, but a 3/4 inch outlet that currently goes down to 1/2 immediatly.

I have an old soapstone sink in my basement that has a hose bib style faucet and I get 80 psi pressure at it, as well as ~ 3.5 gpm of water.

Really need to get at least 8 gpm so that I can eventually run sprinklers. Hoping 3/4 pipe would work but now looking at ID of PEX wondering if I need to go 1 inch.

Thanks

 

[bruceb3]

Remember that PEX fitting are restricted. A 3/4" PEX fitting is 7/16" inner dia. and 1/2" PEX fittings are 5/16" inner dia.. What I'm getting at, is that 3/4" PEX has a smaller inner diameter than 1/2" copper.
You may want to upsize to 1" PEX.

 

[Colbyt]

My house has a 5/8 inch meter that comes into the house, then immediately out of the meter it goes down to 1/2 inch. The 1/2 inch line then goes from the front of the house to the very back (~30-35 feet),
Thanks
Matt
.

Is your meter at the street or in your basement?


Normal is 3/4 copper from a 5/8 meter at the street to house.
3/4 mains inside the house and 1/2 branches.


Whether there would be more than a marginal gain by changing house lines depends on what comes from the street.

 

[HotRodx10]

My house has a 5/8 inch meter that comes into the house,

Not that it affects what you're doing now, but soft copper is sized by outside diameter (OD), while rigid copper is sized by inside diameter (ID). So if the incoming line is soft copper with a 3/4" OD, it's actually nominal 3/4" soft copper.

 

[mholmen71]

Is your meter at the street or in your basement?


Normal is 3/4 copper from a 5/8 meter at the street to house.
3/4 mains inside the house and 1/2 branches.


Whether there would be more than a marginal gain by changing house lines depends on what comes from the street.

I am in the Northeast, so my main is in the basement. It is 5/8 into the water meter, then comes out at 3/4, however it only travels about 4 inches at 3/4 then goes through a reducer 90 angle into 1/2 inch copper.


Realizing that 3/4 pex is ~ .67 inch ID and my current copper is true 1/2 inch I realize that going to 3/4 pex probably will not get me that gain that I want. Goal is to run sprinklers that actually work correctly instead of limited by the 3.5 gpm flow i have now.

I am undecided at the moment on whether to go to 1 inch pex for the main run then T down to 1/2 OR to just run a 3/4 copper line from the meter to the T.

 

[Colbyt]

The more 3/4 you can get after the meter and before the branch circuits you can get the better the pressure will be. The extra run of 3/4 act like a pump holding tank and builds up a reserve and pressure.


Even if your street line is 5/8, that is 5/8 with no turns or restrictions and if the street main has good pressure it should work.