Small Bathroom & Kitchen Water Installation: PEX/AL/PEX, U-type Fittings, Boiler, Taps

Hello, I have a small water installation to do in a small bathroom and kitchen. As in the picture, the length of the wall is about 3 meters.
So I want to do this installation in PEX / AL / PEX on U-type pressed fittings. Please give me your opinion if it is possible to do it as in the diagram below
The main pipe from the water meter 3/4 "and here I want to enter with a pex 20 pipe, and a tee to the boiler for the kitchen and bathroom. In the kitchen, water is further on the tee 20/16/16 for the washing machine and tap. In the bathroom I want to give a pex 20 pipe for the shower and then a reduction for a washbasin and a pex 16 toilet.
Can you do it like this? And will it work ok, or can it be done on pex 20 everywhere?
The installation in the house will be used from the holiday. I will put the pipes in a buffer zone. Bathroom built in GK. Does anyone have pics of how he did it? How did he fasten the approaches to the faucet in the rack? e.t.c..



Added after 1 [hours] 32 [minutes]:

I'm thinking about approaching the washing machine or not doing pex 20, and pex 16 for the shower

It should work. In the toilet, of course, there is a cistern type cistern (the automatic drain would require a PEX20 pipe under the automatic device). PEX16 for the shower and PEX 20 for the washing machine? I think it's better as pictured. The washing machine does not require a PEX20 approach, and the shower - better if it has.

Do you have a pex crimper/press? Because if not, it's cheaper and better to go. Buying a welder will be cheaper than renting it for a few days

Another question. Why is PEX necessary? Can't the installation be made of normal steel (bolted) or copper (brazed) pipes? As for these crimped connections, I do not really believe in their tightness (they must be made very carefully). If I were doing it, I would give steel pipes - instead of PEX20 - 3/4''; instead of PEX 16 - 1/2'' and connected everything with threads. Reliable, tight and in the event of the need for modification (or repair) is the possibility of quite easy disassembly, without damaging the connections.

Buddy, steel has not been used in water for some time.

Zbigniew Rusek wrote:

If I were doing it, I would give steel pipes - instead of PEX20 - 3/4''; instead of PEX 16 - 1/2'' and connected everything with threads. Reliable, tight and in the event of the need for modification (or repair) is the possibility of quite easy disassembly, without damaging the connections

Only here you need a threader, solid wrenches and a pipe cutter. With pp it's scissors, welder and a sharp knife

If the bathroom is small, it is better to drive a separate pipe to each point and connect them in one place to the manifold.

Give it a rest with steel - you need too much work and tools.

Copper - an expensive pipe, it makes sense to use it in places where the pipes are visible and it should look aesthetically pleasing.

PP - nice job, cheap pipes, but thick fittings

Pex under clamp fittings prices kill! PP

woytas73 wrote:

Pex under clamp fittings prices kill! PP

What about twisted pex...

Zbigniew Rusek wrote:

Another question. Why is PEX necessary? Can't the installation be made of normal steel (bolted) or copper (brazed) pipes? As for these crimped connections, I do not really believe in their tightness (they must be made very carefully). If I were doing it, I would give steel pipes - instead of PEX20 - 3/4''; instead of PEX 16 - 1/2'' and connected everything with threads. Reliable, tight and in the event of the need for modification (or repair) is the possibility of quite easy disassembly, without damaging the connections.

You obviously have no idea about installations and installations.
Currently, the law prohibits the installation of drinking water from galvanized steel and copper pipes. Only stainless steel and plastic pipes are allowed.
Durability of installations made of steel and copper pipes is much lower than that of plastic pipes. Steel pipes inside corrode and become overgrown with a mixture of corrosion and scale. However, the biggest disadvantage of copper is the abrasion of the elbows. Installation of copper pipes under the floor is a great risk, because the leak can only be noticed when the entire apartment on the lower floor is flooded. In addition, steel and copper pipes are less resistant to the so-called water hammer and freezing of water inside the pipe. These pipes can burst, especially if they have been used for several years. Here, plastic pipes that retain flexibility are much better.
Steel and copper installations are the most labor intensive and require investment. For steel pipes, you will need a threader, a hydraulic vise, two Stillson wrenches and possibly a pipe cutter or angle grinder or a hacksaw.
In the case of copper, you need a good propane-butane burner, a gas cylinder, a cutter, a deburrer, a set of brushes, cleaners, soldering paste and tin.

For PEX with press fittings, you need a press tool with the right jaws, which is expensive. In addition, shears for cutting pipes and a calibrator. But many stores, when you buy plumbing supplies, rent such equipment. For PEX with compression fittings, only 2 adjustable wrenches, pipe cutters and a calibrator are needed. It's just that twisted systems should not be used under plaster or under the floor.

In the case of PP, you will need a welder, shears and possibly scrapers (if a given type of pipe requires it, and not everyone does).

In sum:
Installations made of PP or PEX pipes outperform installations made of steel or copper pipes in every respect. They are much easier to install, do not corrode, do not overgrow with scale, are more durable and more resistant to damage, are cheaper, and are more hygienic.

Added after 3 [minutes]:

kortyleski wrote:

woytas73 wrote:

Pex under clamp fittings prices kill! PP

And what about twisted Pex...

The prices of twisted fittings are lower than those of crimped fittings.
In addition, the prices of PEX fittings do not kill. When we compare the prices of PEX and PP, it comes out almost the same, because PP fittings are cheaper, but the pipe is more expensive. In the case of PEX, we do not need as many elbows as in the case of PP pipes.

As for durability, sometimes steel pipes (with bolted connections) last more than 50 years and nothing leaks.

But in most cases, after 15 years, it is already heavily corroded and scaled.
Not to mention the fact that filters and batteries are constantly clogged with pieces of rust and scale that break off from these pipes. Very often the batteries are damaged, and each interruption in the water supply is accompanied by the appearance of red, rusty water.

This is how it is with corrosion, but e.g. a plastic pipe is easy to damage when something is punched in the wall and you do not notice the installation (it is easy to pierce it with a hammer - especially when you hit it with a large hammer). Besides, if the connection is not carefully welded, it may leak or leak (much depends on the accuracy of execution) and a welding machine is needed to make such a connection. Steel ones are certainly the most resistant to mechanical damage and allow for modifications of the installation without destroying it (unscrews). In the case of plastic pipes (PP, PEX), any modification is a problem, because the connections are not threaded, so the installation must be cut (this is destruction). Copper - theoretically, it can be desoldered and re-soldered after processing, but it is not as strong as steel (mechanical damage, e.g. caused by impact).

Zbigniew Rusek wrote:

In the case of plastic pipes (PP, PEX), any modification is a problem, because the connections are not threaded, so the installation must be cut (this is destruction).

Total nonsense. Rework of a steel installation, especially an old one, is a serious problem. Just strip off the old thread and it's leaking. At the same time, cutting a pex or pp is nothing. I did some of the steel installation myself a few years ago, but only because I had pipes and tools. I wouldn't do it a second time, especially since the galvanized pipe has already leaked twice in the form of small holes from which water is spraying.

kortyleski wrote:

Do you have a pex crimper/press? Because if not, it's cheaper and better to go. Buying a welder will be cheaper than renting it for a few days

mom crimper on TH and U

Added after 32 [minutes]:

Thank you for all the information.
I understand that the "project" I drew is OK and will work as it should. I bought a press, so the costs are probably behind me ;)

The approach to the WC and WASHING MACHINEs on PEX20 requires changes. Is there a 1/2" connection to each device? e.g. PEX20 and 1/2" output PEX16 and 1/2"?

I drew this BATHROOM and KITCHEN scheme, is it correct now?

Zbigniew Rusek wrote:

This is how it is with corrosion, but e.g. a plastic pipe is easy to damage when something is punched in the wall and you do not notice the installation (it is easy to pierce it with a hammer - especially when you hit it with a large hammer).

You theorize.
So I'm going to give you one typical example of pipe drilling that I've dealt with. The tiler only had to install a toilet paper holder by the lavatory. Unfortunately, he did not remember how the pipes ran. Unfortunately, he didn't have a metal detector, but he drilled until he found it. He drilled the first hole without drilling through the pipe. The second one has already drilled successfully.



To show you what it looked like, I'm posting a photo with drawn elements that were there. Unfortunately, I don't have the original photo after forging these tiles.



As you can see, a galvanized steel pipe, drilled in two places.
The woman reached me through a mutual friend. Crying, she begged me to help her, as she and the tiler had previously called 11 plumbers who refused to do the repair, either right away on the phone, or looking at photos sent via MMS, or after seeing it on site.
An additional problem was that behind this wall was a kitchen that had been renovated. This elbow at the top was connected to the new kitchen installation made of PP pipes and it was not possible to turn it.
Fortunately, we managed to cut the tee and unscrew a fragment of the tee from this elbow. Cramming deeper to grab the pipe with a wrench was out of the question, because there was a possibility of damaging the glass on this wall located behind the renovated kitchen.

So now suggest how you would fix it. After all, you think it's a trivial job.
In my opinion, this is not an easy job, which I undertook to repair as the first of twelve professionals.

Zbigniew Rusek wrote:

Besides, if the connection is not carefully welded, it may leak or leak (much depends on the accuracy of execution) and a welding machine is needed to make such a connection. Steel ones are certainly the most resistant to mechanical damage and allow for modifications of the installation without destroying it (unscrews).

What you write is not true. Removing the drilling of steel pipes is quite a breakneck task without destroying the entire wall. Unless a professional has the right equipment.
In the photos above, the pipes were quite young, because the installation was about 10 years old, because so many years ago the bathroom was renovated there. Only because they weren't old yet, the threads didn't break.
When it comes to welding PP pipes, it is not a complicated operation and unless someone is dirty and does not weld pipes dirty with grease or mortar and follows the recommendations, each connection made will be 100% tight.
It's different with steel pipes. A decent threader costs 2 thousand. PLN upwards Cheap threaders can bend pipes and damage threads, which become leaky and impossible to seal

Zbigniew Rusek wrote:

In the case of plastic pipes (PP, PEX), any modification is a problem, because the connections are not threaded, so the installation must be cut (this is destruction).

On the contrary. Repairing such damage is trivial. Forge a piece of pipe, cut it with an allowance, insert a tee and sockets, and tighten. Half an hour's work - top.

Zbigniew Rusek wrote:

Copper - theoretically, it can be desoldered and re-soldered after processing, but it is not as strong as steel (mechanical damage, e.g. caused by impact).

Copper is very difficult to solder when there was already water in it. Even the smallest droplets that flow down from time to time can cool the pipe so much that cold solders are formed, which can last for several days, and after a few days or months it will start to pour.
In this case, it is much easier to weld PP, because the pipe is thick and is a difficult heat conductor. Copper, on the other hand, is a very good conductor of heat, which is why it is so difficult to solder it when the pipe is wet inside or there is steam inside.

Added after 12 [minutes]:

misio4you wrote:

The approach to the WC and WASHING MACHINEs on PEX20 requires changes. Is there a 1/2" connection to each device? e.g. PEX20 and 1/2" output PEX16 and 1/2"?

For all 1/2" taps and valves
PEX 16 is enough for the washing machine and toilet

Plumpi wrote:

For all 1/2" taps and valves
PEX 16 is enough for the washing machine and toilet

So the first "project" is ok?
So thanks for the information...
I'm going to add a 3/4" filter after the water meter..

misio4you wrote:

So the first "project" is ok?

Basically it's fine.

Is this an apartment, a single family home?
What's your network pressure? Maybe it's worth installing a self-cleaning filter with a pressure reducer

This will extend the life of the boiler.

If you can bend it, bend it. The fewer connectors, the cheaper. Press connectors have no chance of unsealing.
Just don't buy PEX fittings and pipes in supermarkets.
The best type of pipe is PEXc-Al-PEXc
In supermarkets they sell pipes with lower strength. These are usually PERT-Al-PERT, PEXb-Al-PERT or PEXb-Al-PEXb pipes

Plumpi wrote:

Is this an apartment, a single family home?
What's your network pressure? Maybe it's worth installing a self-cleaning filter with a pressure reducer https://www.fermo.pl/produkt-3463-reduktor-ci...yszczacym-honeywell-fk06-34aa-na-34-cala.html

This will extend the life of the boiler.

So it's a one-story summer house I'd call it. Water from the tap..
So add a pressure reducer with a filter..

Added after 7 [minutes]:

misio4you wrote:

small installation of WATER bathroom, PEX kitchen

what do you think about 90 degree elbows in these situations?
elbow or trying to bend the pipe? (fewer connectors are the lesser evil

misio4you wrote:

what do you think about 90 degree elbows in these situations?
elbow or trying to bend the pipe? (fewer connectors are the lesser evil

Bend the most delicate arcs. Having a corner of the walls, you make an arc on one wall, then a piece of straight section in the very corner and another arc on the other wall.



Instead of making sharp bends in the corner when going from floor to wall, you first have the pipes bent along the floor so that they meet in the corner with the wall to which they are to be led, and on this wall again a gentle curve.
Here they were routed in this way, because the wall with the drainage pipe (the one on the left) was to be covered with aerated concrete blocks, and a screed was to be made on the floor.
The wall on the right, however, was to be only tiled.

Hello again.

how to fix the approaches in the wall, gypsum cardboard, e.g. for the shower, to make it solid?



the approaches will be a PEX 1/2" elbow with 2 mounting holes, how to make them protrude from the wall under the tiles properly ...



or just when it comes out, tighten the appropriate extension, etc ...

It doesn't work as it comes out. Approaches must be made rigidly so that the battery does not "fly".
For this purpose, a horizontal section of the profile (e.g. C75 or C100) should be fixed between the vertical profiles. The ends of this profile must be cut and bent so that they can be screwed to the vertical profiles with the help of "fleas" or joined with pliers for connecting profiles. To stiffen this profile, you can put a piece of square timber inside it, and then screw this profile with the square timber using screws. The bends with the claw are then screwed through this profile to the square timber using ordinary wood screws.
The elbows do not have to protrude, because there are extensions for this. The most important thing is to seal the opening between the hob and the elbow or extensions well. Special gaskets (aprons) are used for this. Everything is lubricated with liquid rubber, and then this apron is put on and lubricated again.