Upgrading to 1 1/4" Main Line

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Having had four daughters and their mother in the house: If there had been five showers, every one of them would have run for at least half an hour every morning.

The two boys had enough sense to schedule PE as their first class, and shower at school to avoid battling for the two showers.
 
Having had four daughters and their mother in the house: If there had been five showers, every one of them would have run for at least half an hour every morning.

The two boys had enough sense to schedule PE as their first class, and shower at school to avoid battling for the two showers.

That would come to 12.5 gpm. No problem.

You would need an adequate supply of hot water and be able to deliver it all at once.
 
After 300 ft of pipe and climbing 20 feet and while the lawn is being watered and a load of laundry being run. I hope no one has to poop. There might be a clog.
 
I went out yesterday to mark where the addition will go so I could begin marking the new water main to be trenched. I talked to my dad about the project and he asked if I was sure the line was galvanized. I’d assumed it was because it’s 3/4” galvanized where it enters my basement. But he pointed out that may have been done just so it was sturdy at that location.

We are planning to dig up a bury hydrant today (that I plan to do away with) to see what the size and type of line the main currently is.

So - if it’s currently 1” PVC, I think that’s as big or bigger than 1.25” pex? If that’s the case, I may leave all of the 1” PVC in place and just extend it out with more PVC for the hydrants.

The downside would be that we would be adding on over some aged PVC, and I’m not sure how long it should last? I don’t know how deep footers go, but I guess as long as they don’t go over 3’ down (encasing water line) the line should be replaceable some day?

The upside would be I could avoid my two options of laying a new line: 1. Going under where the addition will be, putting the line inside a bigger PVC. 2. Going north of where the addition will be (so the line is more easily accessed for repairs if need be), which would involve trenching through A LOT of tree roots.

Either way I plan to use PVC at this point, after seeing how much cheaper it is than pex.

What are your guys’ thoughts? Is 1” PVC enough for what I’m wanting (since ID is bigger than 1” pex ID) or should I upgrade it to 1.25” PVC? I’m guessing if it’s anything less than 1” PVC I should replace it all? Is going under the addition (through a “sleeve”) a big deal? Is that worth trenching through a ton of roots to avoid?
 
Since I'm not an engineer I use the upc tables to determine pipe size.

My opinion is you should go through and add up all of the fixtures and piping and take the elevation into account. Then use the table.

I would go by that.
 
Since I'm not an engineer I use the upc tables to determine pipe size.

My opinion is you should go through and add up all of the fixtures and piping and take the elevation into account. Then use the table.

I would go by that.
What about going under the addition in a “sleeve” or going around the addition through tree roots?
 
If you have a feasible plan where you could pull it back out of the sleeve, and feed new back in through it, I don't see a problem. I've done something similar with pex. The 90 bend to go up through the slab was an electrical conduit with a really long bend.

The tree root route I guess would depend on how hard it'll be in reality. Sometimes you think things will be hard and they don't end up being that way.

I think if it were me (and I'm not there in person to get a good feel for what you have going on) I would battle the roots.
 
You shouldn’t pour a slab over pvc water pipe, especially under a foundation.
 
I am planning to do a crawl space instead of a slab. Does that change whether or not it’s ok to build over the main line?

We do not bring pvc water lines inside the foundation walls. Slab or crawlspace.
 
I’m a little slow today and not sure I’m following. I think you’re saying it’s NOT ok to build a structure over a water line?

Not a pvc water line , unless it was sleeved through another pipe and did not terminate within the foundation walls.
 
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PVC is effected by sunlight UV rays
it turns the pipe brittle, That is the reason the code forbids the use of pvc within 5' of the foundation wall

Your best bet, or rather economy wise, run pvc up to the house
then transition to pex using a ball valve under the flower bed
install a plastic valve box

from the internet
1'' pvc Id 1.049
11/4'' pvc id 1.380
1'' pex ID .875
1 1/4 pex id 1.054
 
PVC is effected by sunlight UV rays
it turns the pipe brittle, That is the reason the code forbids the use of pvc within 5' of the foundation wall

Your best bet, or rather economy wise, run pvc up to the house
then transition to pex using a ball valve under the flower bed
install a plastic valve box

from the internet
1'' pvc Id 1.049
11/4'' pvc id 1.380
1'' pex ID .875
1 1/4 pex id 1.054

Buried pvc wouldn’t be affected by uv. It can also be painted.

It’s simply not allowed inside the foundation here because it’s not reliable enough.
 
Update - it looks to me like my water meter is 5/8”. Does this throw a wrench in my plan?

On the PVC, what if I run it up to the foundation wall, then transition to something else to come through the wall. Is that acceptable?
 
Update - it looks to me like my water meter is 5/8”. Does this throw a wrench in my plan?

On the PVC, what if I run it up to the foundation wall, then transition to something else to come through the wall. Is that acceptable?

you’ll get less water through a 5/8 meter. It’s the typical meter for a house.

Sure, you can run pvc then switch to a different pipe, I do it all the time.
 
Not a pvc water line , unless it was sleeved through another pipe and did not terminate within the foundation walls.

My original plan was to sleeve it through another pipe and have all of that under the new addition. From what you guys said, it sounded like that wasn’t ok, so I decided to go around a group of trees, instead. This does add some length to the pipe, but will allow for easier access should the line ever need dug up.
 
you’ll get less water through a 5/8 meter. It’s the typical meter for a house.

Sure, you can run pvc then switch to a different pipe, I do it all the time.
I’m wondering if I’ll have enough pressure/volume with a 5/8” meter? Would it be worthwhile to have the city upgrade my meter to a 3/4”? Maybe even 1”? I thought about doing it some time down the road if I decide I don’t have enough pressure, but it seems like doing it now may be better than waiting until my new line is covered?

What kind of pipe do you typically transition to when entering a foundation/basement wall?
 
I’m trying to figure out the transition from PVC to the water hydrants. I’m looking at using one of three metal pipes - galvanized, stainless steel, and brass. Galvanized is cheapest and brass most expensive. Which is most likely to last longest underground, at the base of the bury hydrants?
 

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