Pressure – No matter what the pressure is on the water authority mains network in the highway, the plumbing arrangement for the water pipes in your home may substantially reduce that pressure by the time it gets to your taps.
Flow – Along with pressure, your water pipes may also be restricting the flow of water to your taps. In other words, the maximum amount of water your pipes can carry will be affected by:
To help you track down the problem and manage your water pressure, here are some examples of some of the most common types of problems:
After flowing through your underground supply pipe, the water goes to your combination boiler. The boiler then supplies all the hot taps inside your home. Combination boilers will not work below certain water pressure levels. While conventional boilers run on as little as 0.5 Bar, combination boilers generally need more for them to function effectively. The pressure your boiler needs may be above the target the local water authority aims to supply in their water mains (1 Bar measured at the boundary of your property). If your plumber has assessed your pressure to be below 1 Bar, it is likely that this is due to the condition of your pipe work. It may also be the case that some combination boilers are capable of supplying only one hot tap with water at any one time (refer to manufacturer). Also, the pressure at your cold-water taps may reduce if they are run at the same time as a hot tap. If you are planning to install a new boiler soon, make sure that your appointed plumber checks that your chosen system will work effectively at the water pressure 1 Bar. Any reduction in this pressure will be due to plumbing issues on your water pipes remembering that water pressure is not constant and that demand, especially during busy morning and evening periods, will reduce water pressure in the water mains network. To remedy this situation, you may want to look at increasing the size of your water supply pipe or renewing the existing corroded pipe work
Water goes to your kitchen tap after flowing through your underground supply pipe. Water then goes to a storage tank in your loft space, and this tank supplies all the other taps in your home as well as your hot-water system. The height of the tank above your supply pipe will affect how quickly it will refill (pressure is lost the higher water has to be lifted). The height of your tank above your other taps will affect the pressure at which water is fed to those taps.
For some properties, the problem is caused by sharing a supply pipe from the water main. This can be a problem if the supply is too small, in poor condition (for example, leaking or old), or if properties sharing a supply use water at the same time. It can also be particularly noticeable at busy times when many properties sharing a supply pipe are placing demands on the water supply. So, a supply that seems fine at some times of the day may not be at other times If you and your neighbour share a supply pipe, you are jointly responsible for it from your property to the boundary stop tap. The houses in the example below have a shared supply pipe and a joint responsibility for maintaining and repairing it. If you have reduced water pressure and you are on a shared supply pipe, talk to your neighbours to see if they are experiencing the same problem. If so, you may want to look at installing a separate independent service pipe from your property to the water main or, at a joint cost, renewing / increasing the size of the shared supply pipe. NOTE: The Local Water Authority may make an additional charge for the connection to the water main.
Flow and pressure in your home will be affected by the length of the supply pipe. On the longer supply pipes, particularly those with a smaller internal diameter, the pipe may be too small to deliver the flow of water to your property that you want even though the pressure is good at the boundary.
Some pressure problems can be caused by faulty, damaged or leaking pipes and fittings, for example ball valves and stop taps inside your home.
Corrosion - If pipes in your home are old, they have become corroded, restricting the water flow. See below difference between old pipe work and new MDPE pipe
Stop Tap - A partly closed stop tap inside your home could be the cause of some water-pressure problems. Gently opening up the tap may increase the pressure. To fully open the tap, you should open and close it several times until the number of turns from open to closed is constant. Do not leave the tap fully open. Turn it back a quarter of a turn to stop it seizing up.
Leaks - Leaks from pipes or fittings will reduce the water pressure. If you have a water meter, check for a leak by taking a reading from your meter just before going to bed and again in the morning before you have used any water. If the figures are different, you may have a leak. If you do not have a meter, listen for hissing sounds from inside pipes or look for damp patches or very obvious green patches on your grass.
Pressure will be affected by the height of a property in relation to the local area around it. If you property is at the top of a hill, you may receive lower pressure than properties that are at the bottom of the hill, especially during busy times of the day such as morning or early evening and during the summer. The local Water Authority will aim to supply a water pressure of 1 Bar at the boundary to your property, however you might want to consider installing a water accumulator. This is a relatively new device that holds water in a vessel during those periods when demand to your property is low and releases that water as you need it at busy times.
The plumbing layout in your property may affect the pressure at which water is supplied to your taps. It may also affect your shower. Many new showers will need a minimum level of flow and pressure to work effectively. Some will need to be supplied directly from the mains (not from a tank in the loft). In older showers, limescale may build up and cause poor flow at the showerhead. Always clean your showerhead every three months to prevent limescale building up. If you cannot remove the limescale, try replacing the showerhead and hose attached to it with new ones. If you are planning to fit a new shower or heating system, make sure you check that your planned system can work efficiently at the pressure of 1 Bar. Any reduction to this pressure is likely to be due to plumping problems with your water pipes.
Sometimes, the installing of new appliances in your property can affect your water pressure. Similarly, someone may have used the stop tap outside your property and left it partially closed. If you have a shared supply pipe, you may not be aware that the stop tap has been used so check with your neighbours.