New water service pipe

[TeaAndBiscuits]

I need to run a new service pipe to my house to replace the current 15mm (I think) pipe from the stopcock in the street (12m or so) and move the entry point to a different room.

I'm going to use an 'Insuduct' to bring the pipe through the wall above ground level as it's a concrete floor. I think where the pipe rises up from the trench and goes through the wall will be 25mm MDPE pipe as it looks like you can get their 'hockeystick' which turns 90 degrees only in 25mm size. Besides, I'd only have to step straight down to a smaller size inside the house anyway.

So the question is - is there any benefit to piping from the street stopcock to the insuduct in 32mm and then reducing down at the bottom of the trench to 25mm to go up the insuduct? Or rather, is there any reason that I should NOT do that and just run 25mm all the way from the street?

 

[PrenticeBoyofDerry]

25mm should be fine

 

[Newboy]

From memory, some water suppliers require an application for supply pipework over 25mm (and some have a higher charge rate for large capacity pipework)

Edit - 25mm not 35mm

 

[TeaAndBiscuits]

Cheers I'll just do 25mm from the street then.

 

[John D v2.0]

I think on meter supplies it's all the same price for sizes.
I'd avoid any joints you don't need, even if it does leave you with 25mm all the way.

 

[dilalio]

What’s the flow rate at the suppliers stopcock and what DHW system do you have (or plan to have) in the dwelling? Ie: what is the potential load that will be put upon the incoming supply in the future?

 

[Ian H]

The only thing with the hockey stick it that it points straight into the room so awkward if your going in behind a kitchen unit.

Sometime we use the hockey stick to come up into the box and then reduce to 15/22mm inside the box.

How much is your Insuduct?

 

[TeaAndBiscuits]

The reason for upgrading the supply is that I'm going to be getting a combi installed and I want the shower to be unaffected if someone flushes a toilet, runs the cold tap somewhere or the dishwasher on or the washing machine is going etc.

Therefore I want to step down to 15mm only at the point of branching off to supply the boiler so that it's never starved of flow if there's another demand(s).

Having the 25mm pipe coming straight out from the wall is not a massive problem, this will be the under-sink cupboard in the utility room. I can turn it 90 degrees with an elbow as soon as it enters then the stopcock, then step down to 22.

I don't plan to use the top box (groundbreaker) thing, just the insuduct to get the pipe up from the ground and through the wall. But yeah I guess I could maybe step down to 22mm copper in the insuduct.

What do you mean by how much is my insuduct? The price?

 

[Ian H]

Yes price, just wondering what they cost.

 

[TeaAndBiscuits]

I haven't bought it yet, looks like it's about £70 including the 'hockey stick'. Expensive for what it is but it seems like it's got the market to itself really.

Much cheaper than breaking up and relaying a concrete floor!

 

[TeaAndBiscuits]

Hi again all, I put this bit of my project on the back burner for a bit, while I took care of a few other things. Back to the water now though.

I dug down to my current water pipe at the boundary in the hope that it would be lead and I could get it replaced for free, or alternatively it might be 20mm black plastic, which I could just connect a new 25mm MDPE pipe to. Actually it turns out that it's 15mm copper all the way from the street.

So I had the water company out to give me a price to connect up a new pipe and apparently the main is on the other side of the road and it will cost over £2k to mole in a new pipe to my boundary. In the quote they have specified it's to connect a 32mm pipe and a 15mm meter. I queried the 15mm meter and the reply came back that "A 15mm water meter is the correct size meter up to and including a 32mm supply pipe. This will not effect the flow rate of the supply. "

Is this correct? Surely if all the water flowing through the supply pipe first passes through the meter then that will significantly restrict the flow? OK, it'll be better with just a short length of 15mm than with 15mm all the way, but it'll still be a restriction?

Cheers

 

[Ian H]

I thought 25mm was the standard meter size.

 

[John D v2.0]

The resistance is roughly speaking the diameter reduction times the distancel, so having 6 inches of 15mm won't cause a big issue other than noisy flow there. Not sure which part of the meter is 15mm, presumably the connection, normally they would be bigger.
The other thing is that"correct" for them is at least 1 bar and i think 8l per minute at your side of the stop tap, either way not much. So they would prefer to fit a smaller meter to save cost regardless.

 

[TeaAndBiscuits]

Thanks for the responses all.

Just to update this, I've done a bit more digging today, right up to the boundary and uncovered this:

The street stopcock is on the other side of the fence panel on the right.

The 15mm copper from the house joins onto.... lead pipe? That's what it looks like to me. I can gouge it with a craft knife and it's definitely not magnetic.

Hopefully that means I can get it replaced for free. Not every day you find over £2k buried in your garden eh?

 

[polesapart]

Deffo Pb.