Valveless manifold

[Mr Blobby]

I had assumed my plumbing manifolds would be fitted with individual isolation valves.  

 

 

Assuming my plumber has no intention of fitting valves to these manifolds, then please tell me that (a) it doesn't matter, or (b) an alternative product with valves.

 

Three of our HW (showers and bath) pipes are wider diameter than the rest.

 

Edited Saturday at 19:10 by Mr Blobby

[JohnMo]

The biggest advantage of a manifold is the isolation valves in my opinion. They allow parts of the system to taken offline while the rest stays active.  No a no valve manifold is a missed opportunity. Just look at Screwfix they offer a couple of different options.

[-rick-]

What did you specify/agree to for this installation? Has he put isolators at the other end?

 

That would be what I’d imagine an uncreative plumber not used to installing manifolds would do. (afaik isolators somewhere are a requirement, exact location isn’t)

 

I don’t see the logic in doing it that way. You want a way to isolate leaks. Best place to do that is at the branch point of the circuit (*). Gonna be a pain in future if you want to change things as is. So I would put my foot down in your position and have them fitted at the manifold.

 

* whether you want a second isolator at the end of the pipe is a question. If they are already there I don’t think I’d bother removing them. My experience with isolators is that they have leaked more than I’ve needed to use them as isolators, so I think I’d be inclined not to duplicate. Though from reading here it sounds like the leak issues are common with cheapo/screwfix type isolators. Higher quality ones are good.

Edited Saturday at 19:59 by -rick-

[Mr Blobby]

Ok, so I could have been more specific, but really, specifying a manifold without valves is like specifying a car without wheels.  I didn't think I needed to be that specific 😒

 

The problem is my trades always want to do everything at least cost because that's what they always do.  It's just frustrating.  Assume nothing 😬

 

Can valves be inserted here at the junction, or is it entirely new manifolds?

[-rick-]

4 minutes ago, Mr Blobby said:

Assume nothing 😬

 

indeed. I try not to assume but when I do it often comes back to bite me.

 

4 minutes ago, Mr Blobby said:

Can valves be inserted here at the junction, or is it entirely new manifolds?

im not the best person to ask but i believe yes. But if you’ve got a plumber who will always install cheapest available option then you may want to put some effort into specifying better quality valves (or expect leaks at some point).

[JohnMo]

For the cost of manifolds, swop the manifolds for proper ones. These are the first ones I found many other options out there, they just screw together to make as many outlets as you need. Others in the site 

 

https://www.bes.co.uk/riifo-plumbing-manifold-3-4-x-1-2-valved-outlets-4-port-red-levers-27474/

[Mr Blobby]

Does the diameter of the manifold matter?

 

Maincor do a manifold that connects straight to the mlcp pipes but only the 1 inch manifold has connectors for 20mm mlcp.

[G and J]

OK, I’m going to risk sounding dumb now, but is it really worth the effort to replace the manifolds?   Maybe ensure a few isolators are put in so that just the cold or just the hot can be shut off, but given that the horse has bolted will enough time be saved in the future to repay the extra time and delay (and the knock on effects of a pissed off tradesman)?

 

If there’s a leak you shut down, deal with it pronto or whack a stop end on the offending bit till you get the parts.  
 

I maybe guilty of Hep2O think here, but I put isolators everywhere in our last house and in 34 years most of them never got closed off. 

[Conor]

I just put a 22mm isolating valve on each of the manifolds. Not the end of the world.

[Nickfromwales]

2 hours ago, Conor said:

I just put a 22mm isolating valve on each of the manifolds. Not the end of the world.

I'm with you if it saves the cost of "fixing this", but a PITA if @Mr Blobby needs to isolate 1 room.

 

@Mr Blobby Assuming these don't have isolators means your plumbers have installed isolators at each termination point; where this is possible eg kitchen / utility / basins / behind bath panels for bath & showers?

[Mr Blobby]

11 hours ago, Nickfromwales said:

Assuming these don't have isolators means your plumbers have installed isolators at each termination point; where this is possible eg kitchen / utility / basins / behind bath panels for bath & showers?

 

No, no isolators on the other ends that are plumbed so far.

 

Call me cynical, but the way it seems to work is tradesman finds a day he needs to fill.  His regular merchant doesn't have the bits in stock, so substitute with whatever is on the shelves. 

 

I texted the plumber yesterday and haven't heard back so he probably isn't very happy.  But he's going to charge me twice for doing it twice so I don't see the problem.  Besides, this isn't a popularity contest, it just needs to be done right.  The trades already think I'm a pita so I've nothing to lose 😆

 

 

[Nickfromwales]

I guess the M&E spec should have been tighter? Did you tell him to fit manifolds with isolators?

[Mr Blobby]

On 30/06/2026 at 13:54, Nickfromwales said:

I guess the M&E spec should have been tighter? Did you tell him to fit manifolds with isolators?

 

 

... the manifolds were first fitted on the wrong (as per the MandE drawings) wall and I got them moved. But they are still in the wrong place so the cold to the kitchen is now going to be doing its own thing 🤦‍♀️

 

There's no way the plumber is ever going to read the M and E specs 🤷‍♂️ 

 

(Although in fairness a bunch of stuff changed since the original M and E spec hence I'm to blame for not being too strict after the documents were issued)

 

 

Edited 8 hours ago by Mr Blobby

[Mr Blobby]

🤦‍♀️  

Edited 8 hours ago by Mr Blobby

[Nickfromwales]

4 hours ago, Mr Blobby said:

the cold to the kitchen is now going to be doing its own thing 🤦‍♀️

It can't do its own things, it needs to be off a balanced cold feed to comply with G3.

 

Plumber sounds like a tit tbf, but if you handed him the spec and he did not grace you with his time to read it, then he'd be told to GFH and pay to change the manifolds on his own time and money.

 

If you didn't then you've fallen onto your own sword.