Plumbing is not just about lengths of PVC or copper! A small revolution in the field, the PER makes life easier for professionals, as well as for amateurs, wishing to carry out their installations in complete autonomy. What is it about ? How to choose and connect it? We tell you everything!
What is a PEX tube?
It is a high density cross-linked polyethylene pipe. Under this technical name, hides in reality a semi-rigid pipe, designed specifically to create domestic (hot and cold) water networks, in the fields of plumbing or heating; its big difference with the copper pipes being in the fact that the welds are not necessary, replaced by connections mainly screwed or crimped.
What is the difference between PER and multi layer?
The multilayer embeds all the advantages of the PER. In addition to being able to be installed exposed or recessed, it offers easier bending than other materials, better resistance to pressure, as well as to temperature variations. It is, however, more expensive than the PER.
What are the advantages and disadvantages of PEX pipes?
PER has various advantages, making it particularly popular in recent plumbing installations:
- It is economical;
- Its lifetime is similar to that of copper;
- Not easy to scale;
- Can not subject to corrosion;
- Very easy to handle and implement;
- Relatively light;
- It can be installed seamlessly over very long lengths;
- It offers good acoustic insulation during the circulation of water;
Like any equipment, it also has its share of disadvantages, relatively small, if we take into account the advantages mentioned above.
- The prices of its fittings remain relatively high;
- Left visible, the PER degrades under the effect of UV. This pose is therefore not recommended;
- Its curvature margin is reduced, compared to copper;
- Its thermal expansion can quickly stress its fittings;
How to choose a PEX pipe? The criteria to check:
Opting for PER tubes means taking into account a certain number of criteria before going to checkout. Among these :
Colour: Blue for cold water, red for hot water. PEX pipes are very easy to identify, but this criterion must still be taken into account, depending on the need;
The diameter: It must be adapted to the flow of water in the installation; two numbers, corresponding to the interior and exterior measurements, then allow you to make the right choice;
The rate of deformation, or coefficient of expansion: sometimes considered as the weak point of the PER;
How to create a PEX network and connect the tubes?
Do you want to create your own piping network, to connect your sanitary equipment or your household appliances? Follow the leader !
To begin, know that you can only intervene on certain parts of your installation.
In the house, you cannot touch the part of the installation before the meter, and the meter itself;
In an apartment, you can only intervene from your water meter; the rest of the piping under the condominium;
To complete, and in any case, the installation of non-return valves remains mandatory, under the regulations.
1. Get the right parts:
As an indication, it is recommended to opt for the following (external) diameters when choosing your PEX, for a pressure of 3 bars (beyond, a pressure reducer must be installed):
- Shower, washbasin, WC, dishwasher, washing machine…
- Bathtub, water station...
- Sink, bath…
- Electric water heater…
Finally, find out about the need to install manifolds for hot and cold water (headers) and various shut-off valves, depending on the isolation needs of each circuit. Here are some plumbing tips you should know
2. Choose your distribution type:
When it comes to designing a PER network, two concepts stand out:
Hydro-cabled distribution (octopus), where each sanitary device has its own power supply from the same collector, placed in the technical shaft;
Transplanting on the general installation, where each device is connected using a specific tee;
Whatever the case, it is preferable to install the pipes behind lining plates, or in grooves – if they take place in walls, or directly in the ground.
3. Take the right precautions:
Before starting, remember to close all your water supplies, then drain the circuits, by opening all the taps.
4. Install, connect, power:
This step involves creating connections, progressing in the opposite direction of the distribution (from the supply points, to the collectors). To facilitate connections: