🗓️ Maintenance Calendar
Low Water Pressure at Home: Causes and Fixes
Is it one tap, one floor, or the whole house? Where the problem appears tells you where to look.
Dana Whitlock · Oct 24, 2026 · 6 min read · 4 steps
Weak showers and slow-filling baths are frustrating, and the cause can be anything from a clogged aerator to a problem with the mains supply.
Start by working out how widespread the problem is. That single question narrows the causes dramatically.
Just one tap or shower
If only one outlet is weak, the problem is almost always local. Unscrew the aerator on the end of the tap or the shower head and soak it in white vinegar for an hour to dissolve limescale. Check that the small isolation valve on the pipe under the sink is fully open — they are sometimes left half-closed after a repair.
Hot water only
If cold water is fine but hot is weak, look at the water heater or boiler. A combi boiler with a partly blocked heat exchanger or filter can restrict flow. Hot water cylinders fed from a tank in the loft rely on gravity, so pressure on upper floors is naturally low — a pump may help, but get advice before fitting one.
The whole house
When every outlet is weak, check:
- The main stopcock is fully open
- Whether neighbours have the same problem — it may be the supplier’s network
- For a sudden drop, look for signs of a leak: damp patches, a running meter with all taps off
- For older homes, narrow or corroded supply pipes, which may need replacing
When to call in help
Your water supplier can usually tell you the pressure they provide at the boundary and whether there are works in your area. If the supply is fine but pressure inside is poor, a plumber can test flow rates and advise on pipe upgrades, booster pumps, or accumulators.
This is general home-maintenance information, not professional advice. Building codes, permits, and safe practices vary by location — consult a licensed contractor, electrician, or plumber for work beyond your experience.