ᐅ What is the water pressure in the cold water supply line?

Hello,

I wanted to ask you what the optimal pressure is for the cold water supply line?
We have a semi-detached house with bathrooms and water connections on a total of 3 floors.

The water connection is in the basement, where we also have a washbasin.
On the ground floor, we have a guest toilet, and on the upper floor, there is a bathroom with a bathtub and a shower.

Currently, the pressure is 3 bar (43.5 psi), but, for example, the water pressure in the kitchen is quite low (this might also be due to the faucet). The lawn sprinkler doesn’t reach very far either.

What would be your recommendation for water pressure?
What is the upper limit before it becomes harmful to the pipes and fittings?

Generally, a pressure of 4 bar is assumed, although I would rather locate the problem in the kitchen faucet. Often, there are some nonsensical water-saving inserts that negatively affect the whole system.

I can’t say anything about watering the lawn – our grass has to take care of itself.

I personally run the house at 3.5 bar, but that’s more a personal preference; I also tend to drive my cars at low revs...

I have also read that 4 bar is the standard.
But to be honest, I wouldn’t even know how to check that myself.
Turn on the valve, fill a 10-liter (2.6-gallon) water bucket, and time it? Strictly speaking, that only measures flow rate. For pressure, there must be something else involved, right?

Jesse Custer schrieb:

Generally, 4 bar is used as a guideline, although I would suspect the issue in the kitchen is more related to the faucet. Often, there are some poorly designed water-saving inserts installed that negatively affect the flow.

Is 4 bar the standard pressure setting, or should 4 bar be considered the maximum limit, not to be exceeded because, for example, from 4.5 or 5 bar it becomes critical or damaging for pipes and fixtures?
There are usually some fluctuations in the water pressure in the pipes anyway.

We currently have 3 bar and I’m thinking of increasing it to 3.5 or 4 bar.

Tolentino schrieb:

Honestly, I have no idea how to check that myself.

We have a water filter in the basement where we can check and adjust the water pressure.

In my case, the water comes directly from the supplier into the house without a pressure reducer – it is always between 4.5 and 5 bar (65 and 73 psi).

FrankChief schrieb:

Are the 4 bar (58 psi) a standard setting, or should 4 bar (58 psi) be the maximum limit and not exceeded because, for example, pressures above 4.5 or 5 bar (65 or 73 psi) become critical or damaging to pipes and fittings?

It’s not critical. Unless some poor-quality work was done that could cause everything to break apart.

Inside the house, 3-4 bar (44-58 psi) is common; in multi-family buildings, the upper floors often receive even lower pressure. Water suppliers typically deliver between 4 and 8 bar (58 and 116 psi) into the building.
Your home’s plumbing should be designed for 10 bar (145 psi). So there is more than enough capacity.

Tolentino schrieb:

Strictly speaking, that is only the flow velocity.

No, that is the flow rate in liters per minute (l/min).
Flow velocity in meters per second (m/s) is irrelevant in a single-family house.
The water filter pressure reducer is set between 3-4 bar (45-60 psi).

FrankChief schrieb:

For example, the water pressure in the kitchen is too low.

You might try unscrewing the faucet outlet, soaking it in a cup of vinegar for a few hours, rinsing it with water, and reinstalling it.
With Berlin water, this maintenance is necessary annually.