10 Way Water Manifold

[village idiot]

I have been instructed to provide a 7 Way Manifold feeding 7 flats as part of the installation job I am doing.
The mains water comes into the property in 32mm MDP pipe.
I have decided to then reduce this into SEVEN 15mm outlets to the various flats (customer wanted to buy a manifold from SF but I told him I will just manufacture mine.
My gut feeling tells me it is highly unlikely the flat owners will be able to have a decent pressure? Am I wrong? Is there a better way of supplying the individual flats?
I asked the customer if the flats will all have sufficient pressure from the 32mm supply? He said Thames Water had informed him when they fitted it that he could even feed as many as 10 flats.
I am considering removing the 28mm end caps on both ends and adding two more inlets, (so I have 3 28mm feeds as opposed to just the one I currently have in the middle).

 

[Meady]

Were doing one like that at the moment with 10 flats and they have a 50-60mm water main, can't remember the exact size so that seems very small to me.

 

[village idiot]

He claims the supplier was informed of his requirements before the installed the mains.
I will be well piizzed off if all floor is secred etc then asked to redo

 

[Ermintrude]

Were doing one like that at the moment with 10 flats and they have a 50-60mm water main, can't remember the exact size so that seems very small to me.

Pressure will be cack anyway! I would have done it in 54mm and fitted check valves and prvs on each supply . Turn on top flat and open all the others and record lowest pressure , set prvs to that. Then u low that the top will be getting same as ground floor . Shouldn't there be a rpz valves on each zone?

 

[josh]

Nice and neat, check valves are fine as far as i remember.

 

[Ermintrude]

Identify the valves and meters by flat number not plot !!!! How may times have u been doing a TT or capping off and it's plot 549 apartment. 3 ( not flat as posh)

 

[Ermintrude]

Lay a 63mm service as a contingency!

 

[village idiot]

Erm, I just fitted double check valves to the individual supplies. May be in future I will fit RPZ valves, but considering they are mainly ideal for fluid category 4 risks, I doubt I will bother.

 

[newcastle phill]

Rpz
Would be used on direct connection sprinkler systems or abattoirs etc, fluid category 3 or 4 up

 

[oz-plumber]

The whole scenario would be based in the incoming water pressure.
What is the incoming water pressure?

I would be very wary of taking a customers word from second hand information from a water supply company.

It will be your bum on the line at the end of the day - not his /hers or theirs.

Do some homework and get yourself comfortable with being right.

 

[AWheating]

32mm is too small for 7 flats, 32mm is for 1 very large dwelling or 2 small to medium dwellings.

http://www.unitedutilities.com/documents/DesignManualIssueMay2012.pdf

look at page 16 of this document, it gives a table of recommended sizes and indicates you need 63mm tho i think you would be ok with 50mm and 25mm to each flat from a proper manifold.

you want to fit a proper meter manifold like this
http://www.plasson.co.uk/gallery/upload/Product Information/Meter Manifold Assemblies 2012.pdf

Polypipe also make these and will make one to suit your requirements ie. with 7 connections if you ask them, probably take 2 weeks tho.

 

[Ermintrude]

So flat one has a shower flat 7 has Asian who washes his arris with shower hose connected to taps over toilet another flat opens up and hmmm. Why didn't we fit decent protection. You have no control over what each flat does, fitted rpz!


We used them on auto fill systems

 

[newcastle phill]

Well youd have to get written consent to use one and also ensure its tested annually, but I havent seen any in flats ive been to, not saying it doesnt happen but usually commercial and industrial with them and not suitable where theres low pressure
Would be a good idea over benwell to prevent the by-products from the cannabis irrigation systems filtering back into the supply lol

 

[wetdrip]

Rpz
Would be used on direct connection sprinkler systems or abattoirs etc, fluid category 3 or 4 up

Human waste is a fluid 5 category?
Or I'm I looking at the incorrect material...talking 5hit
https://www.affinitywater.co.uk/docs/HLA-protecting-the-customer-09.pdf

 

[Ermintrude]

Most of the kier blocks got BCW from storage tanks? Walker and teams beautiful

 

[newcastle phill]

Human waste is a fluid 5 category?
Or I'm I looking at the incorrect material...talking 5hit
https://www.affinitywater.co.uk/docs/HLA-protecting-the-customer-09.pdf

True, but its not connected to a main, usually protected by 2 air gaps in domestic otherwise everyhouse would have an rpz lol

 

[Ermintrude]

Don't think that a rpz is allowed on cat 5 needs to be physical gap

 

[village idiot]

The whole scenario would be based in the incoming water pressure.
What is the incoming water pressure?

I would be very wary of taking a customers word from second hand information from a water supply company.
It will be your bum on the line at the end of the day - not his /hers or theirs.

Do some homework and get yourself comfortable with being right.

Oz, you are right in your observations, but in this scenario, I'm really not bothered.
Before I attended, they had ran the incoming supply from Water supplier side to inside of property and Covered it all up and paved over it. When I queried the 32mm size, he informed me that he does it all the time and has never had any issues? Well. considering he knows so much, who am I to complain?
I can't wait for when all the flats have been occupied, then they all have to have a shower at 6/7am. I can see tempers flaring and neighbours demanding the other turn off their shower and wait till they have had theirs
Can't wait to see his face when the complaints begins. Even my trying to nodge his builder in the right direction drew a blank. He too says it shouldn't be a problem as they have done it loads of time. Great

 

[lame plumber]

your dooomed. Doomed I say to complaints coming back again and again. Only decent way is individual supplies, but landlords hate the cost

 

[village idiot]

your dooomed. Doomed I say to complaints coming back again and again. Only decent way is individual supplies, but landlords hate the cost

Believe you me, I will sleep easy.
If this scenario is going to be the eye opener for him and his builder to realise that it PAYS to get someone in advance to advice before proceeding, then so be it.

they have done it before, they say, so me here, I just do as they please, take my money and move on. I did inform the builder (customer will not entertain any deviation from his plan) that it is not whether they will have to dig up the 32mm and re-pipe it, but when.

 

[plumben]

Got to love It when people think they know best, even though your the professional and you've spent the 4+ years in training and your years of experience

 

[Dannypipe]

I've read somewhere that its a good idea to create those manifolds in a loop as it helps balance the flow. Don't know if there is any truth to it. Perhaps not as the factory made manifolds would probably do the same.

If the main service pipe is undersized, you could poss put flow regulator valves on the outlets to give everyone their equal share. But no means perfect but it might help.

 

[Ermintrude]

Just have a headder couple of sizes up from leg

 

[oz-plumber]

Oz, you are right in your observations, but in this scenario, I'm really not bothered.
Before I attended, they had ran the incoming supply from Water supplier side to inside of property and Covered it all up and paved over it. When I queried the 32mm size, he informed me that he does it all the time and has never had any issues? Well. considering he knows so much, who am I to complain?
I can't wait for when all the flats have been occupied, then they all have to have a shower at 6/7am. I can see tempers flaring and neighbours demanding the other turn off their shower and wait till they have had theirs
Can't wait to see his face when the complaints begins. Even my trying to nodge his builder in the right direction drew a blank. He too says it shouldn't be a problem as they have done it loads of time. Great

In that case - make sure you document everything incl. dates and converstaions and who was present.
And detail / itemize everything on your invoices.

You may need a 'get out of jail card' in the future - and you are certainly not going to get one off the builder.