Upgrading to 1 1/4" Main Line

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JG plumbing

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I can respect your marching to your own drummer, this guy can take your advice and you might be right I'm just telling you what the code book says. If he gets some home inspector that looks at the code when he goes to sell this place there could be an issue, but likely not.
 

Twowaxhack

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I don't know where you keep coming up with two inch this is another thing where you need to read.

The only thing the number of bedrooms determines, is the size of the water heater.
In this post you say it’s on the borderline of needing a 2” pipe.
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Here in this post you say 1.25” is ok.
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I’m just trying to figure out what your book suggests. Can you post your suggestion ?
 

JG plumbing

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Right on the border is right on the border, but he's on the 1-1/4"side.
 

Twowaxhack

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Right on the border is right on the border, but he's on the 1-1/4"side.
so from the border of 2” we skip 1.5”and arrive at 1.25” ? Is that what the book says ?

You posted he’s right on the border of needing a 2” pipe.

Can you read it ? You posted it......

I underlined it in red for you.
 

JG plumbing

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In that pressure relm yes. There isn't a big enough difference between the two as far as the code is concerned.
 

Twowaxhack

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In that pressure relm yes. There isn't a big enough difference between the two as far as the code is concerned.
If your book says that then I guess it must be true, that’s why their code book is garbage when it comes to residential sizing.

No code would require this man to have a 1.5” meter.
 

Twowaxhack

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So the book says he needs a 1.5” meter with a 1.25” water main but it’s close to needing a 2” water main.

Is that right ?
 

JG plumbing

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The pressure drop at the meter is why they upsize it. He's close to the minimum pressure. That's why it's goofy.

I don't have the book in front of me but I think 46 units is where it jumps to 2".
 

Twowaxhack

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The pressure drop at the meter is why they upsize it. He's close to the minimum pressure. That's why it's goofy.

I don't have the book in front of me but I think 46 units is where it jumps to 2".
My entire street has a 4” main @55 psi and you’re books trying to tell me this guy needs a 1.5” meter @45-50 psi at the meter.
 

JG plumbing

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A 4" pipe is 4 times bigger than a 2" pipe. Pipe size is a function of the square. You can't just guess.
 

Twowaxhack

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A 4" pipe is 4 times bigger than a 2" pipe. Pipe size is a function of the square. You can't just guess.
That’s right, and that’s why if a pipe is borderline needing to be 2”, a 1.25” wouldn’t do the job.,

How much bigger is a 2” pipe vs 1.25 “ ?

Do you realize that a 1.5” meter will flow around 50+ gpm at 45 psi ?

Do you really think that house is going to use anywhere close to 50 gpm ?
 

Twowaxhack

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We have apartment buildings here that has 1.5” meters at 55 psi that serve 8 units each.

Just built, just got off the phone with the contractor who piped the complex.
 

JG plumbing

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Your mixing and matching. This is why we don't get along, you don't follow lines of logic. You just take left turns.
 

Twowaxhack

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Your mixing and matching. This is why we don't get along, you don't follow lines of logic. You just take left turns.
We don’t get along because you think 2” pipe is borderline but 1.25 is the correct size.

That’s called crab walking. It simply doesn’t make sense.

We also don’t get along because you think your book is always right but the fact is that the book changes quite frequently because code writers often disagree. I also believe your interpretation is incorrect as well.

No code would require this man to have what’s considered a commercial meter in almost every municipality in America.
 

Twowaxhack

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Ok here's the book. A 1"meter can do 38 units. A 1.5 can do 45. So add up the units again and see. I think i came up with like 40 I don't quite remember. I think i figured 6 each for his hydrants.

Again, your book is adding units for fixtures that will not be in use !!!!!!!

I don’t care how many sinks he has, they all will not be running.

I don’t care how many bathrooms he has because they’re not all going to be used at once., Not even close !

Why would how many bathrooms he has matter ? How many can his family use at once ?

Why put something into an equation that has no realistic affect on his use ?

It’s similar to how many electrical outlets can you put on one 20 amp breaker. You could put 50 or as many as you want but you just can’t use them all at once..

Same principle here.

There are 50+ homes on my street. 4” main. We all have 5/8 meters with 1” pvc mains. Neighborhood is 25 yrs old. 55psi. 100’ from the meter.

I have 4 full bathrooms and a half bath. ......and a crap load of sinks.

What’s your book say about that ? No complaints at my house.,
 

JG plumbing

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Do what you want man. The industry will move on without you.
 
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