A weak shower, a tap that takes forever to fill a pot, a boiler that struggles to fire when you open the hot tap: in most cases the culprit is low water pressure. Sometimes the problem is with the mains supply, sometimes something inside the house is to blame and you can sort it yourself. Before calling a plumber, here are the checks and solutions worth knowing.
Checking whether the pressure really is too low
Ideal household water pressure sits between 2 and 3 bar. Below 1.5 bar you start noticing a difference; below 1 bar the shower becomes uncomfortable and some appliances stop working properly. The simplest way to find out is a pressure gauge screwed onto an outdoor tap or the service pipe connection. They are inexpensive and give you an immediate reading. Without measuring, any action is guesswork.
The most common causes inside the home
- Clogged aerators and showerheads. Limescale blocks the small filters in taps and showerheads. Often the pressure elsewhere in the house is fine and the problem is isolated to a single outlet.
- Pressure reducing valve set too low. Many installations have a PRV at the mains entry point. If it is incorrectly adjusted or has failed, it throttles the pressure even when there is no reason to.
- Old, scaled-up pipework. In ageing installations, limescale builds up inside pipes, narrowing the bore and restricting flow.
- Weak mains supply. In some areas, particularly upper floors or properties on the fringes of the network, the mains simply does not deliver enough pressure.
Quick fixes to try first
Start with the easy wins. Unscrew the aerators from taps and the showerhead and soak them in white vinegar for a few hours to dissolve limescale, then refit them. Check the pressure reducing valve: it has an adjustment screw or knob, and a small upward tweak sometimes solves everything. Also confirm that the stopcock at the mains entry is fully open. It is more common than you might expect to find it was left half-closed after a previous job.
When a booster pump or accumulator is needed
If the mains pressure is inherently low, no amount of cleaning will fix it. The real solution is a pressure booster system: a pump paired with a small accumulator vessel that maintains steady pressure throughout the house. It is the standard remedy for top-floor flats, isolated properties, or installations with many draw-off points. You will find booster sets, pumps, and pressure reducing valves in our plumbing section, sized for different household demands.
What you can do yourself versus what needs a professional
Cleaning filters and adjusting the PRV are straightforward DIY tasks. Installing a booster pump is a different matter and should be left to a plumber, because the pump capacity needs to be matched to the system and the connection point matters. Avoid oversized pumps on the assumption that more power means more pressure. An oversized pump stresses pipework and fittings and can cause water hammer. Steady, correct pressure is worth more than excessive pressure that nobody can control.
Frequently asked questions
What is the ideal water pressure for a home?
Between 2 and 3 bar. Below 1.5 bar you notice the difference at taps and in the shower; above 4 bar you risk damaging pipework and seals. A pressure gauge on any tap tells you the exact figure in seconds.
Can I increase pressure without a pump?
Sometimes yes. If the problem is limescale in the aerators or a PRV set too low, cleaning and adjustment are enough. If the mains supply is genuinely weak, a booster system is the only lasting solution.
Do booster pumps use a lot of electricity?
No. They only run when water is drawn off, and the accumulator vessel reduces the number of start cycles. Electricity consumption for normal domestic use is modest. Choosing the right capacity for the property matters far more than worrying about the running costs.