What is the best pipework system for a life inside the wall?

[MikeSharp01]

I have to run some pipework inside the wall around one of our showers. I had decided on plastic (HEP / JG or some such) but I have to turn it 90 deg inside the wall and then another 90 deg to bring it out of the wall. I can get it 50mm deep and protect it behind a metal duct cover along the run and the wall will be tiled anyway. My concern is the two 90 deg bends and their reliability over the N years the house will be up. I wonder if I might be more sensible to run this in copper or use compression fittings on the plastic pipe for the 90 deg bends. (I will pressure test it once it is in and before the wall coverings go on naturally.) I have a load of JG push fit fittings that have held sound for 10+ years now back at millstone manor although I can get at all of them if needs be.

 

Any thoughts?

[Declan52]

Just keep a spare tile or  two and  make  note of where the bends are.  Write it in marker on the back of  the spare tile and put the tile in the attic.   If the leak happens, very unlikely but can happen,  then it's only a tile of, cut your way through and replace the 90 bends.  

[MikeSharp01]

24 minutes ago, Declan52 said:

then it's only a tile of, cut your way through and replace the 90 bends.  

Makes sense will have to find a virtual 'attic' as we don't / won't have one here.

 

[joe90]

Ask @Nickfromwales about hep 2o longevity.

Edited November 15, 2018 by joe90

[Pete]

It depends on how acute your bends are as the pipe makers supply a former that goes around the outside of the pipe to create a 90 degree bend thus doing away with a join

[MikeSharp01]

2 minutes ago, Pete said:

acute your bends are as the pipe makers supply

Great idea - I have not tried bending this pipe tight, I will look it up, but I guess I could and I have got about 80mm depth to turn 90 deg.

[MikeSharp01]

5 minutes ago, joe90 said:

Ask @Nickfromwales about hep 2o longevity.

What will he say I wonder - he is something of an evangelist for HEP as I recall it.

[ProDave]

Soldered copper for me with bends formed in the bender rather than elbows where possible.

[PeterW]

Hep2O all the way - Wavin guarantee it for 50 years and I would not be mixing copper compression and plastic pipe anywhere...

 

You "could" go with copper but I'd use long street elbows to reduce the restriction if you did.

[MikeSharp01]

18 minutes ago, Pete said:

pipe makers supply a former

HEP do supply a former, it can deliver 120mm radius, I wonder if I can squeeze it down a bit more, will give it a try later.

 

3 minutes ago, PeterW said:

Wavin guarantee it for 50 years and I

Yes but will they pay the bill for the damage or the water used I suspect not. One of my former colleagues had a push joint fail and it wrecked his whole house, he was out for 6 months while they fixed it. It was a new build and the builders blamed their plumbing contractor but in the end his house insurance picked up the whole tab and are, as far as I am aware, 4 years later, still chasing the builder. 

 

11 minutes ago, ProDave said:

Soldered copper for me with bends formed in the bender rather than elbows where possible.

Yes that is the way I wanted to go but its a pain to get in, and I will need soldered joints somewhere.

 

If I can get a 90 deg bend into 80mm I will go with HEP I think otherwise - given my colleagues experience I will find a way to get the copper in there.

 

Thanks all for you support...

[joe90]

I have gone all hep20 in my new build, the only 90’ bends are on the back of the shower valves built into the wall. The advantage of plastic is long runs with no joins or restrictions given by tight 90’ bends (unless you need a couple like me). I was a copper only plumber till I used hep20 and heard about how good it was from @Nickfromwales.

[MikeSharp01]

Ok, quick trial with a wooden former and I can get the pipe in with a 90 deg bend, so I will build formers into the wall and run it as one continuous length of HEP 2 pipe. 

 

PS Other air handling companies are available - but perhaps they don't give out free scale rules at exhibitions.

[scottishjohn]

that is exactly my concern with these push on fittings  -how long will the seals last/#Ihave decided to use uponor q&e system which is basically a strech the pexA to fit unions ,with special tool then it shrinks back down --

no joints anyway where cannot get at them -pipe comes inrolls -

heres avideo   https://uk.video.search.yahoo.com/search/video?fr=mcafee&p=uponor%2Butube#id=4&vid=c86882d49856a9efcb0c9c5259c01c91&action=view

Edited November 15, 2018 by scottishjohn

[PeterW]

8 minutes ago, scottishjohn said:

that is exactly my concern with these push on fittings  -how long will the seals last/#Ihave decided to use uponour q&e system which is basically a strech the pexA to fit unions ,with special tool then it shrinks back down --

no joints anyway where cannot get at them -pipe comes inrolls -

heres avideo   https://uk.video.search.yahoo.com/search/video?fr=mcafee&p=uponor%2Butube#id=4&vid=c86882d49856a9efcb0c9c5259c01c91&action=view

 

The Uponor system is pretty crap tbh and won’t get widespread uptake due to the cost of the equipment and the lack of maintainability. You will still need standard connectors to everything such as taps, tanks and pumps etc. 

 

Press fit have been around since the 1990’s when they came out from the hydraulics industry and have never caught on. 

 

 

[Onoff]

I wanted to run to my towel rad with no joints in the 16mm pex-al-pex. Coukdnt get 'em tight enough!

 

 

Edited November 15, 2018 by Onoff

[Triassic]

Run it in 10mm then ........

[joe90]

I must admit I ran 10mm for hot feeds to basins and the flow rate is excellent.

[Jeremy Harris]

O seal joints have a heck of a long lifetime, so they would be the least of my worries.  There are tends of thousands of miles of MDPE water pipe buried around the country that all relies on O ring seals at the joints.  There are 40+ year old black alkathene pipes with O ring fittings at my late Mother's farm, a fair few of them just in the open by water troughs etc, and I don't think there's ever been a seal failure - the only failures I can remember are when a pipe out in the open has failed and pushed the fitting off, and I think that's only ever happened once (may well have been that the fitting wasn't secured properly, too).

 

Similarly, buried foul drain pipe has been using O ring push fit seals for decades, and I've never heard of them failing.  Admittedly they aren't under pressure, but if O ring degradation was a problem they'd still start leaking sooner or later.

 

According to the manufacturers, EPDM O rings have an unlimited life when used within their normal limits, which seems to support the view that the lifetime of O ring based fittings is likely to be greater than any of our lifetimes.

[joe90]

The only failures I have heard of is when the pipe is scratched before fitting, not allowing the o ring to sit properly. I was taught to protect the pipe where fittings were to go.

[Alexphd1]

Uponor mlcp with pressfit fittings. Unfortunately not diy as the machine is pretty expensive, but NEVER had a leak yet. 

[scottishjohn]

1 hour ago, PeterW said:

 

The Uponor system is pretty crap tbh and won’t get widespread uptake due to the cost of the equipment and the lack of maintainability. You will still need standard connectors to everything such as taps, tanks and pumps etc. 

 

Press fit have been around since the 1990’s when they came out from the hydraulics industry and have never caught on. 

 

 

hardly that expensive -bought a s/h tool on e -bay with batteries +charger +3 dif size adpaptors £100--.but buy all your stuff from uponor for a house and they give you at tool if spend is £750

std fitting-- as in they screw onto taps etc and all plastic or even copper to plastic adpators ,but joint to piping of these fitting  is same shrink fit .the other davantage is no restriction in flow rate you get full pipe diameter as pipe goes over fitting -this is not the same as those that use clamp rings -eveything is plastic . only thing that is crap is your attitude to a system you don,t know  or have used cos you want to go cheap 

you want see strength of joint watch this

https://uk.video.search.yahoo.com/search/video?fr=mcafee&p=uponor%2Butube#id=4&vid=c86882d49856a9efcb0c9c5259c01c91&action=view

- 

[PeterW]

33 minutes ago, scottishjohn said:

only thing that is crap is your attitude to a system you don,t know  or have used cos you want to go cheap

 

Sorry John but you have no idea about my knowledge or what I've previously done so I neither appreciate or find that comment helpful - for reference I have a significant amount of experience around M&E systems and controls going back more than 2 decades so my attitude is one based on experience rather than manufacturers website and YouTube videos.

 

34 minutes ago, scottishjohn said:

buy all your stuff from uponor for a house and they give you at tool if spend is £750

 

I have to say if you spend £750 on a single house pipework then there is something VERY wrong ..!! The total first fix pipework - both in "cheap" Hep2O and copper for a 3 bed, 3 bath house recently done has just nudged the £250 inc VAT mark as it was decided to do the plant room in copper not Hep2O. That is everything including all tap tails, ASHP, tank connections, and other items you CANNOT do with your snazzy Uponor stuff as the MIs require you to use copper for such as boiler tails. 

 

MCLP does have its place, and its used extensively in commercial premises where there are long runs and also for ease of install and to prevent alteration by users. The concept of using this in a residential build is limited as it is not easily adapted as there are very few (ie none) fittings available at mainstream suppliers that can be used without the tooling and so it cannot be modified by consumers so is likely to be a reason for not purchasing it.

 

[Onoff]

2 hours ago, Triassic said:

Run it in 10mm then ........

 

Too late! With hindsight etc.

[ProDave]

The reason I personally don't like push fit is my experience 15 years ago on our first self build.  We bought an old static caravan, and as soon as we connected it to the mains water (I admit about 6 bar) one by one all the push fit connectors started blowing off in some cases the fittings actually cracking.  I ended up re plumbing it in copper.

 

It was probably a poor system used (I never did find out the make) and was probably 30 years old, but it has clouded my judgement about push fit plastic ever since.

 

But the whole point of push fit of course is the pipe comes on a roll, not in 3M lengths, so you can do a long run where it is hidden without joints, and just make sure the joints at the ends are accessible.  I have used some left over Pex/Al/Pex UFH pipe like this for one run that would have been very hard indeed to do in copper.

[scottishjohn]

56 minutes ago, PeterW said:

 

Sorry John but you have no idea about my knowledge or what I've previously done so I neither appreciate or find that comment helpful - for reference I have a significant amount of experience around M&E systems and controls going back more than 2 decades so my attitude is one based on experience rather than manufacturers website and YouTube videos.

 

 

I have to say if you spend £750 on a single house pipework then there is something VERY wrong ..!! The total first fix pipework - both in "cheap" Hep2O and copper for a 3 bed, 3 bath house recently done has just nudged the £250 inc VAT mark as it was decided to do the plant room in copper not Hep2O. That is everything including all tap tails, ASHP, tank connections, and other items you CANNOT do with your snazzy Uponor stuff as the MIs require you to use copper for such as boiler tails. 

 

MCLP does have its place, and its used extensively in commercial premises where there are long runs and also for ease of install and to prevent alteration by users. The concept of using this in a residential build is limited as it is not easily adapted as there are very few (ie none) fittings available at mainstream suppliers that can be used without the tooling and so it cannot be modified by consumers so is likely to be a reason for not purchasing it.

 

 no I don,t k now who you are or what you have done --but calling things crap is not helpful when you don,t even see the difference in the 2 systems

your choice of course is yours as to whatsystem you want  ,but don,t call something crap when definately is not

Q+E is not MCLP- total different system  anyway .

maybe you should look at some videos before making sweeping statments

and if some intinerant chippy or other trade swings on the plumbing it is not coming apart

long runs is the point no joints anywhere but on each end.

and it will look much prettier when used exposed if using the striaght lengths and very slim shrink fittings

I understand £750 is unlikley on a single build hot+cold only --that is why i bought my tool s/h--but add the underfloor piping + manifolds,valves pumps ,controllers  etc ,etc 

I also intend to have everything in a plant room with manifolds and stop taps for  circuits 

I would never suggest any sort of plastic close to a boiler ,but as we ain,t using a boiler -but heat pump  that ain,t a problem either.

 

this forum  as I understand  it  is to give  info and choices  and solutions to problems-which I did .

joints behind walls --just don,t have them is the fall back postion by choice and if Ihave to have a90bend through bad planning i want one that is bulletproof

Edited November 15, 2018 by scottishjohn