The Content Of The Article:

Copper, PER, multilayer? Before starting plumbing work, it is important to determine which material will make up the supply network. For this, we must first look at the quality of its water.

Test the pH of the tap water.

Depending on the nature of the water - acidic, neutral or basic - it may be discouraged to choose a particular material. Indeed, too acidic, water may cause corrosion of copper, which can generate long-term leaks along the network.

Start by measuring the acidity of the water

It's the pH some water (potential hydrogen) which allows to measure its acidity on a scale of 0 to 14. With a pH lower than 7, the water is acidic. Greater than 7, it is basic. It is neutral if its pH is close to 7. We find, in the trade or on the Internet, kits allowing to test oneself the water of its faucet. In the territory, the reference defines as qualitative a water of which the pH is between 6.5 and 9.
If the water is too acidic for copper, the solution is then to choose a synthetic material like PER or multilayer, insensitive to corrosion. Thanks to its aluminum oxygen barrier (BAO), the multilayer is mainly intended for the heating water network. But, although it is more expensive than PER (cross-linked polyethylene), its resistance, its conditioning in crown or tube and its easier bending make it not uncommon to find it in water installations health.

Hard water: what impact on plumbing?

With regard to the hardness of water, limestone deposits do not save any plumbing material, even if with PER and multilayer the risk is less. Expressed in degrees Celsius (° C) or more often in degrees Fahrenheit (° F), the hardness of water is measured as a function of hydrometric title (TH) using commercially available tests.
TH of less than or equal to 8° F demonstrates that the water is very slightly calcareous, between 8 and 20° F the water is slightly calcareous, between 20 and 30° F it is calcareous and is considered very hard beyond 30° F.
Finally, setting the temperature of domestic hot water is also a determining factor. The hotter the water, the higher the degree of limestone and the more deposits there are on the internal walls of the pipes. To limit scaling, the water temperature must be between 55 and 60° C.

What solution for what cost?

Sanitary installation comprising two tubes with connections for a shower and a washbasin.

Between the copper, the PER and the multilayer, not easy to find there. To guide you, here are three detailed specifications for the same installation including two tubes with taps for a shower and a sink.

Installation estimate made in PER: 119 €

AMOUNTPRICE (€)
Lever brass ball valve 1/2219
Female straight fitting swivel nut 16 x 1/226
16 x 1.5 sheathed PER tube3 m4
Reduced crimping tee 16-16-12214
16 x 1.5 sheathed PER tube2 m3
Fixed male and bicone crimping connector 16 x 1/226
12 x 1,1 x 12 "x 12" sheathed tube (washbasin)7 m9
Crimp sleeve equal Ø 1226
Elbow crimp equal 90° Ø 12211
12 x 3/8 male and bicone crimping connector25
Flexible braid in stainless steel in 1/2 female. Length: 50 cm218
Various supplies (necklaces, rosettes, screws...)18
TOTAL119 €

Diameters expressed in mm. Price incl. VAT at 20%.

Installation estimate made in multilayer: 184 €

AMOUNTPRICE (€)
Lever brass ball valve 1/2219
Rotating nut connection to crimp 16 x 1/2215
16 x 2 Pexal multilayer pipe in a crown3 m7
16 x 2 Crimp Connection Tee225
Pexal multilayer pipe 16 x 2 in crown (shower)2 m5
Male straight fitting 16 x 2-3 / 8 crimp213
Pexal multilayer pipe 16 x 2 in crown (washbasin)7 m17
16 x 2 crimp connection sleeve216
90° connection elbow to crimp 16 x 2218
Male straight fitting 16 x 2-3 / 8 crimp213
Flexible braid in stainless steel in 1/2 female. Length: 50 cm218
Various supplies (necklaces, rosettes, screws...)18
TOTAL184 €

Diameters expressed in mm. Price incl. VAT at 20%.

Estimated installation done in copper (traditional): 189 €

AMOUNTPRICE (€)
Lever brass ball valve 1/2219
Rotating nut fitting to crimp 16 x 1/2218
Copper tube 1/2 hard 16 x 13 m21
Copper crimping tee 16-14-12222
1/2 x 1 1/2 hard copper tube (shower)2 m11
14 x 3/8 bronze transition piece to be crimped29
1/2 x 1/2 hard copper tube (shower)7 m34
Copper sleeve to crimp Ø 1426
Copper elbow crimp Ø 1225
12 x 3/8 bronze transition piece to be crimped28
Flexible braid in stainless steel in 1/2 female. Length: 50 cm218
Miscellaneous supplies (necklaces, rosettes, screws...)18
TOTAL189 €


Diameters expressed in mm. Price incl. VAT at 20%.


Video Instruction: How to Choose Water Supply Piping - This Old House