Property renovation, re-plumb advice req`d

[Steve]

Hello, first post and i`m looking for a bit of advice please.

I have recently bought a 3 bed end terrace, and i`m going to be gutting it and completely re-plumbing it to replace the lead pipes, inc new boiler, and i`m moving the bathroom around.

I`m an engineer and decided to do as many of the jobs in this project as I can. Best way to learn, would just like some guidance and sound out some of my ideas with the pro`s.

From where the water enters my property which will be with mdpe, then a stop tap, am I correct in thinking that this converts to 22mm pipe?

If so I was thinking to reduce the pressure drops with multiple water demands, I would plumb 22mm pipe to the main areas (kitchen, bathroom & C boiler) then convert via manifold in each room to 15mm for the respective components, is this the norm? and will it solve the problem of pressure drops?

Any help tips and advice would be greatly appreciated.

Cheers

 

[plum ber]

Sound good to me just don't forget to cilp all pipework and don't use pushfit IMO I am sure the rest will agree, I now hate pushfit... Good luck with it though

and if you replace the incoming water main do it to a depth of 750mm and UU (united utilities) do a free connection for lead replacement call them for further advise, and if you do good luck breaking through the perma frost.....if you find any gold 50% to me pls for advise

 

[Best]

Firstly, what sort of hot water plumbing system are you wanting? Combi boiler or unvented system or gravity? You also need the mains supply pressure & flow rate tested to see if adequate.
A 25mm pipe entering the house will need a 25 x 22mm stopcock to take you to copper. Mains flow rates to cold supplies will rob other taps to some extent anyhow. You are right to think of running 22mm to main areas, like boiler room, & to upstairs.

 

[Best]

That's a good point Plum ber said - get entire lead mains replaced no matter what work involved!

 

[Steve]

Thanks for the replies,

I have already got approval from UU, they will connect for free.

Is the way I suggested the norm, or are the rooms normally supplied with 15mm?

I am getting a new combi boiler.

As for the copper, I was actually thinking of using Hep2o, why is this such a bad idea?

Plum ber, you can have 33% of any gold found, I figure 1/3 for owning land, 1/3 for doing work, 1/3 for advice.

 

[lame plumber]

Get quotes to install your boiler, pick the guy you want to work with, let him do the boiler and use him here and there on a day rate and pick his brains for help. So he has some work, will help you out and advize when needed. I do this occsionally for people, but dont expect him to do you full plans etc such that you can drop him thereafter, you'll end up needing help somewhere and he''ll charge a fortune at that stage, ie when building regs appear and want proof of correct works or the water co wants bits signing off, for that you can pay them direct or get an"WRAS approved plumber" to do the work and sign off, much cheaper

 

[Koogatubac]

Manifold on a cold water distribution pipe?!!
And other plumbers are agreeing to this?
You dont put manifolds on cold water pipes, its normally heating! Also if you wanting to reduce pressure, put a PRV (Pressure Reducing Valve) just above your stop tap. You dont have to have a MDPE x 22mm stop tap. You can get MDPE x 15mm stop taps, depending on how many cold water outlets inc bathrooms u have

 

[Best]

Is the way I suggested the norm, or are the rooms normally supplied with 15mm?

As for the copper, I was actually thinking of using Hep2o, why is this such a bad idea?.

You can go to each bathroom with 22mm & reduce to supplies after that for all cold taps. Hot is another matter, as smaller pipes will be less loss, & quicker etc. Just remember if you use too large a pipe its no big deal.
As to plastic or copper pipe - there's loads of debate on this forum about it, but copper is the best for heating providing it's done right. Plastic is not cheap after you count the cost of all the fittings, clips, inserts.

 

[Gray0689]

Manifold on a cold water distribution pipe?!!
And other plumbers are agreeing to this?
You dont put manifolds on cold water pipes, its normally heating! Also if you wanting to reduce pressure, put a PRV (Pressure Reducing Valve) just above your stop tap. You dont have to have a MDPE x 22mm stop tap. You can get MDPE x 15mm stop taps, depending on how many cold water outlets inc bathrooms u have

Why do you not

 

[Gray0689]

You can go to each bathroom with 22mm & reduce to supplies after that for all cold taps. Hot is another matter, as smaller pipes will be less loss, & quicker etc. Just remember if you use too large a pipe its no big deal.
As to plastic or copper pipe - there's loads of debate on this forum about it, but copper is the best for heating providing it's done right. Plastic is not cheap after you count the cost of all the fittings, clips, inserts.

Why is copper best
More efficient to have heating on a manifold whether underfloor heating or radiators every room individual controlled

 

[lame plumber]

Having seen all the suggestions to date, you may now realise why I said make friends with a local plumber, and give him some work :29:

 

[Best]

Manifold on a cold water distribution pipe?!!

I wasn't agreeing to that! Lol! People use the wrong terms & I have been wondering was he thinking of heating pipes as he also mentioned "to each room".

 

[Best]

Why is copper best
More efficient to have heating on a manifold whether underfloor heating or radiators every room individual controlled

Just meant if he is going to do a basic system, especially below floorboards, then a quality copper job with end feeds will never give any bother.
Plastic pipe in pipe & to manifolds may be a good choice.

 

[Gray0689]

Just meant if he is going to do a basic system, especially below floorboards, then a quality copper job with end feeds will never give any bother.
Plastic pipe in pipe & to manifolds may be a good choice.

Yes copper best if going for a very basic system

 

[plum ber]

Manifold on a cold water distribution pipe?!!
And other plumbers are agreeing to this?
You dont put manifolds on cold water pipes, its normally heating! Also if you wanting to reduce pressure, put a PRV (Pressure Reducing Valve) just above your stop tap. You dont have to have a MDPE x 22mm stop tap. You can get MDPE x 15mm stop taps, depending on how many cold water outlets inc bathrooms u have

Thought it was branching off a main feed pipe, sorry too chuffed at uploading log cabin piccies #agree and my bad

 

[Steve]

Sorry, I will try to make myself clearer...

Off the 25mm mdpe i was going to have 3x 22mm pipes, on to the kitchen, one to the bathroom and one to the boiler.

Off each of these pipes in the kitchen and bathroom i was going to have a 22mm manifold with 15mm outlets.

Off the bathroom manifold 15mm outlets i would supply toilet, sink, shower and bath. Kitchen manifold would supply sink, washing machine etc.

Is this a stupid way of doing it? I just thought if I could get a greater of volume of water to that area it would avoid pressure drops?

 

[plum ber]

I have done this before aswell and it worked really well it was in a bathroom but neat and tidy if ever I go back to the job isolation is really quick and easy I will try and find a pic also

 

[Best]

Sorry, I will try to make myself clearer...

Off the 25mm mdpe i was going to have 3x 22mm pipes, on to the kitchen, one to the bathroom and one to the boiler.

Off each of these pipes in the kitchen and bathroom i was going to have a 22mm manifold with 15mm outlets.

Off the bathroom manifold 15mm outlets i would supply toilet, sink, shower and bath. Kitchen manifold would supply sink, washing machine etc.

Is this a stupid way of doing it? I just thought if I could get a greater of volume of water to that area it would avoid pressure drops?

Just need to come off stopcock in 22mm & keep going to each main point in 22mm, then tee down to 15mm to small supplies like toilets & basins.

 

[Gray0689]

No mate sounds good
But you could just go to a central point ie hot press and do your manifold from there

 

[plum ber]

Just need to come off stopcock in 22mm & keep going to each main point in 22mm, then tee down to 15mm to small supplies like toilets & basins.

but there is nothing wrong with running into the room in 22mm then into a manifold and split from there for the various appliances ie in bathroom behind the bath, then all you have to do is whip off the bath panel to isolate every appliance individually??

 

[Best]

but there is nothing wrong with running into the room in 22mm then into a manifold and split from there for the various appliances ie in bathroom behind the bath, then all you have to do is whip off the bath panel to isolate every appliance individually??

I would be more than happy with each bathroom having it's own isolating valve but take your point. I think any main isolators should be somewhere handy & all labeled as to where they feed.

 

[Steve]

Just need to come off stopcock in 22mm & keep going to each main point in 22mm, then tee down to 15mm to small supplies like toilets & basins.

If I come off the stopcock with 22mm and then split 3 ways wil that not defeat the object of trying to reduce pressure drops?

I was thinking: mdpe (25mm) - stopcock - short 25mm pipe to manifold (25mm in and 3x 22mm outlets) ???

 

[Koogatubac]

Why do you not
View attachment 9280

Is that picture on a 3 bed end terrace property?
I meant i havnt seen a manifold on a 3 bed end terrance property mate

 

[Gray0689]

No mate it's not lol
But no reason it can't be very simple to do and yes will be more expensive in short term but on heating side will be better in long term imho

 

[Best]

If I come off the stopcock with 22mm and then split 3 ways wil that not defeat the object of trying to reduce pressure drops?

I was thinking: mdpe (25mm) - stopcock - short 25mm pipe to manifold (25mm in and 3x 22mm outlets) ???

I know what you are thinking, but to use 25mm pipe to the manifold will make no difference to the flow rates. 25mm is much the same as 22mm copper.

 

[Koogatubac]

No mate it's not lol
But no reason it can't be very simple to do and yes will be more expensive in short term but on heating side will be better in long term imho

you've done cold water distrubution pipes on manifolds have you mate?

Heating via manifolds like that (UFH?) i prefer than radiators

 

[Gray0689]

you've done cold water distrubution pipes on manifolds have you mate?

Heating via manifolds like that (UFH?) i prefer than radiators

Yes mate if you look at that picture the ones in bottom right corner are domestic hot and cold manifolds
The rest are to the radiators
no underfloor heating

 

[JCplumb]

I think that this is being over cooked somewhat. This is a 3 bed terrace not a block of flats Use copper as it's less likely to fail especially if you're hiding it under tiled floors etc. Plastic is good and reliable but ONLY if done right. Whereas if your copper installation isn't leaking on day one, it probably won't be leaking on day 10,000.
15mm everywhere will be fine for hot and cold runs if your incoming main has decent pressure and you're installing a combi/sealed system, manifolds to supply a bathroom are overkill IMO, use ISO's to isolate units. The only reason I would think manifolds were first mentioned is because someone has been looking through the John Guest brochure and thought 'ooh that'll work'

 

[Gray0689]

I think that this is being over cooked somewhat. This is a 3 bed terrace not a block of flats Use copper as it's less likely to fail especially if you're hiding it under tiled floors etc. Plastic is good and reliable but ONLY if done right. Whereas if your copper installation isn't leaking on day one, it probably won't be leaking on day 10,000.
15mm everywhere will be fine for hot and cold runs if your incoming main has decent pressure and you're installing a combi/sealed system, manifolds to supply a bathroom are overkill IMO, use ISO's to isolate units. The only reason I would think manifolds were first mentioned is because someone has been looking through the John Guest brochure and thought 'ooh that'll work'

Nothing is overkill if someone wants it done lol

 

[Koogatubac]

Good work grey

 

[Nostrum]

Sounds like you may be over engineering a simple 3 bed semi re-plumb to me, I take it your going for an unvented cylinder and thermostatic showers in multiple bathrooms etc? Or are you trying to peel your spuds with water pressure in the kitchen sink :tongue3:.

It's all going to be relative to the spec of the rest of the house as to whether or not it is worth doing something like this.

 

[markfxy]

If youre fitting a combi theres no point running 22mm just do it all in 15mm use push fit it's quicker and easier done properly pushfits fine, if youre not a plumber your more likely to get a leak with copper

 

[plum ber]

I think that this is being over cooked somewhat. This is a 3 bed terrace not a block of flats
someone has been looking through the John Guest brochure and thought 'ooh that'll work'

You could be right there with the overcooked part but I have used a manifold in a bathroom before and it worked really well but it was a complete bathroom room swap the lot. So the boss ordered manifold's to be used instead of iso valves.....will put a pic on if I can but I will say it was one of the first jobs I did and was bent using a spring not a bending machine.

 

[gavinwilson]

Would it not be worth finding out what your pressure is coming into the house and then working out what it will be with new bathrooms/ proposed pipework runs then you can work out what you can get away with why spend money if you don't need to ?

sent from my annoying box

 

[Koogatubac]

3 bed end terrace ant gunna be that big. Just sufficient to put a combi say worcester 40 in, could run up to 1x bathroom, 1x en-suite, 1x kitchen.

Re-do all plumbing either way. Plastic or copper depending on budget and time.

New bathroom and heating system. Jobs a gud en! Easy peasy