What size water pipe, is there a handy online calculator?

[Doing it for the kids]

Planing a much needed upgrade and need to run water around 200m, down hill to a number of residential and commercial property.

The current supply comes 350m via a 63mm blue pipe off a bore hole but will eventually be mains via a holding tank. There will be over 10m of head so at least 1 bar of pressure. I will in due course split it 3 ways to serve tall the property.

If there an online guide? Currently thinking x3 50 mm as I can’t seem to find anything between 32 and 50.

I think each resi needs 32mm at such low pressure rather then 25

 

[Lakesdigger]

Planing a much needed upgrade and need to run water around 200m, down hill to a number of residential and commercial property.

The current supply comes 350m via a 63mm blue pipe off a bore hole but will eventually be mains via a holding tank. There will be over 10m of head so at least 1 bar of pressure. I will in due course split it 3 ways to serve tall the property.

If there an online guide? Currently thinking x3 50 mm as I can’t seem to find anything between 32 and 50.

I think each resi needs 32mm at such low pressure rather then 25

Why via a holding tank with mains?
If water company find out you are going to be storing their water and then distributing to multiple properties they won't be keen on giving you water. They also don't like commercial and domestic supplies off the same pipe as a rule.
I don't know if all properties are in the same area but why not run one bigger pipe rather than 3?

 

[Doing it for the kids]

Had a year arguing with them. They don’t have the infrastructure to supply us direct pressured so we have to install a tank. They will fit a main meter then leave us to maintain all the pipes to each premises. We then have to fit a meter to each which they bill direct. The main meter is just to check we are behaving.

Currently on a chuffing bore hole that’s knackered. The farm has another which I’m keeping quiet about. I’m yet to tell them about the commercial, I may just label it as farm and leave it there!

Sadly the needs are in 3 different ways so little choice. Going to be a lot of big pipe going in!

 

[Lakesdigger]

Probably don't want any less than 50mm for the main runs then in that case. I'd expect that would be plenty big enough but does it allow for any extra at a later date?

 

[Doing it for the kids]

Potentially more to come hence my concern.

Pondering a ring main on 2 of the 3 spurs before they hit the meters to help balance and pressure drops.

An online calculator would be very handy like a volt drop for armour cable

 

[onesiedale]

but if they are supplying you to a meter then it must surely be a pressured supply

 

[Doing it for the kids]

Sadly not.

I have to run over 1km of pipe i think to get to their POC. They did talk about a pump but with so many power cuts that’s not good. They thus agreed to a holding tank on hill. Buffer will help their low pressure, be about 10-15k volume.

Naturally I have to pay for it all. I asked them to just have one big meter but they have so far refused. Finding or replacing the supply pipes with meters is going to be the most hassle

 

[onesiedale]

surely though, 1km of 32mm pipe will carry the pressure fine to supply any number of properties. You just need to put a sub meter in for each

 

[Doing it for the kids]

32mm? Typo I guess?!

I think they wanted minimum 63 barrier pipe. I fought them on that and they eventually backed down to non barrier.

I will end up with a low pressure feed from them. The head I can offer fixes that though, I just need to work out bore for the end user.

The buffer tank will soften their low flow rate as well

 

[C.J]

1 bar is not much pressure - our shower needs 1.5 Bar and you will lose 0.3 Bar every floor.

 

[Wisconsonian]

10m is more than 2bar, and adequate pressure for anything. You will lose head with a second floor bath obviously, but still adequate. The pressure loss from flow is the other factor, but still 1" should be adequate these days, so 32mm is a safe choice if there's no imminent additions. There are plenty of calculators to show what pressure at what head, or what flow with various diameters. The minimum is set by the plumbing code, but you don't want minimum, even if fewer people are living in bigger houses, and using lower flow plumbing fixtures. A taller reservoir will add a bit of marginal pressure when full, and fill faster from the low pressure supply when low. I'd be replumbing the reservoir to fill from a small diameter and pressure regulated valve, but feed the outlet directly most of the time, and have a check valve to accept water from the reservoir only when the pressure drops below the reservoir head, not as complicated as it sounds.

It all sounds like enough hassle to figure out a way to keep using the bore hole to me.

 

[essex man]

Have a km here to mains water.
Water comes down it to our buildings, tenants in them, farm supply, farmhouse and 8 other houses.
Been a while since i saw pipe thankfully, it's not very big.
Not at big as 63mm from memory.
Pressure isn't great, the houses can't have pressurised plumbing systems.
If i refill sprayer tank at full bore then flow beyond(everything) is a dribble.
Been like this for fifty years.
Previously an enormous holding tank in roof of farmhouse used, it's still up there as impossible to remove without cutting up.
I think you should go for as big a pipe and tank as affordable!

 

[onesiedale]

32mm? Typo I guess?!

no.
We run 2km through our place to a sub metererd industrial property. (quarry + 2 dwellings)
all in 32mm pipe.
no problems

 

[Kentishfarmer]

Had a year arguing with them. They don’t have the infrastructure to supply us direct pressured so we have to install a tank. They will fit a main meter then leave us to maintain all the pipes to each premises. We then have to fit a meter to each which they bill direct. The main meter is just to check we are behaving.

Currently on a chuffing bore hole that’s knackered. The farm has another which I’m keeping quiet about. I’m yet to tell them about the commercial, I may just label it as farm and leave it there!

Sadly the needs are in 3 different ways so little choice. Going to be a lot of big pipe going in!

Why not just fix the borehole? It will save you in the long term, water is only going to go up and water company customer service is only going down.
A lot if us are going the other way to you and putting in boreholes on perfectly good mains.
With your pressure and pipe calculations the size of your holding tank is something to take into account. The larger the tank so the greater the weight of water forcing its way out will also increase your pressure above what you generate from the 10m head change

 

[C.J]

10m is more than 2bar, and adequate pressure for anything. You will lose head with a second floor bath obviously, but still adequate. The pressure loss from flow is the other factor, but still 1" should be adequate these days, so 32mm is a safe choice if there's no imminent additions. There are plenty of calculators to show what pressure at what head, or what flow with various diameters. The minimum is set by the plumbing code, but you don't want minimum, even if fewer people are living in bigger houses, and using lower flow plumbing fixtures. A taller reservoir will add a bit of marginal pressure when full, and fill faster from the low pressure supply when low. I'd be replumbing the reservoir to fill from a small diameter and pressure regulated valve, but feed the outlet directly most of the time, and have a check valve to accept water from the reservoir only when the pressure drops below the reservoir head, not as complicated as it sounds.

It all sounds like enough hassle to figure out a way to keep using the bore hole to me.

This is incorrect

10 meters is 1.05 Bar

 

[suffolksmallholder]

Having experienced thermoweld pipe couplings I would strongly suggest that you used these if possible.
Once they are done you will never have issues with poor joints.
Fit a trace wire as well.
SS

 

[br jones]

Pity ,they just replaced a main local to me ,ran a 63mm 2k down the hill as a temporary supply ,brand new .,when finnished chopped it up inro lengths to fit in skip

 

[mezz]

this table may be useful for you, showing pressure drops per 100m

 

[flinty123]

Pity ,they just replaced a main local to me ,ran a 63mm 2k down the hill as a temporary supply ,brand new .,when finnished chopped it up inro lengths to fit in skip

Not allowed to use the pipe again due to contamination risks

 

[Adeptandy]

Just bear in mind if your going through a meter at source there's only so much flow that can be achieved.