Weak showers, taps that trickle and a washing machine that takes forever to fill are frustrating. Low water pressure has many possible causes, from a simple blocked tap aerator to a hidden leak or a problem with the municipal supply. This guide helps you narrow down the cause, fix the simple problems yourself and recognise when you need a plumber.
Step 1: Work out where the problem is
Before looking for a fix, answer three questions. They narrow down the cause quickly.
- Is it one tap or the whole property? One tap points to that fixture. The whole house points to the supply, the main valve or the pipework.
- Is it hot water, cold water or both? Low pressure on hot water only usually points to the geyser or its valves.
- Did it start suddenly or gradually? A sudden drop suggests a supply interruption, a burst pipe or a valve being closed. A gradual drop suggests build-up or corrosion.
Common causes of low water pressure
1. Municipal supply interruptions or maintenance
In Johannesburg, planned maintenance, pipe bursts in the street and strain on the supply network can all reduce pressure or cut water off completely, sometimes in specific areas or at peak times. If the whole property is affected suddenly, ask your neighbours and check for notices from your municipal water provider before calling a plumber. Pressure often returns to normal once the supply is restored.
2. Blocked aerators and shower heads
Tap aerators and shower heads have fine screens that catch sediment and mineral deposits. Debris often comes loose in the pipes after the water has been off and comes back on. Unscrew the aerator or shower head, rinse it out, soak it in white vinegar if there's scale, and refit it. If pressure improves, you've found the problem.
3. A partly closed stopcock or isolating valve
Valves are sometimes left partly closed after maintenance work. Check that the main stopcock (often near the water meter) and the isolating valves under basins and toilets are fully open. Turn them gently. Old valves can be stiff and may start to leak if forced.
4. Hidden leaks
A leak diverts water before it reaches your taps and can also push up your water bill. To check: turn off every tap and water-using appliance, then look at your water meter. If it keeps moving, water is escaping somewhere. Other signs include damp patches, mould, unexplained wet areas in the garden or the sound of running water when everything is off. Hidden leaks need professional leak detection to find the source without unnecessary damage.
5. Geyser valve problems (hot water only)
If only the hot water is weak, the pressure control valve on the geyser supply may be faulty or blocked, or a valve may be partly closed. Because geysers involve pressure, heat and electricity, have a qualified plumber check them. See also our article on signs your geyser needs replacing.
6. Old, corroded pipes
Older properties may still have galvanised steel pipes. Over time, rust and scale build up inside them and narrow the bore, so pressure drops gradually over years. Replacing affected sections with modern pipe is the long-term fix.
7. Pumps, tanks and water backup systems
If your property uses storage tanks with a booster pump, low pressure can come from a pump fault, a blocked filter, an airlock or a tank that has run low. These systems are common in Johannesburg because they keep water available during interruptions, but they need to be correctly sized and maintained.
Quick troubleshooting checklist
- Check with neighbours whether the supply in your area is affected.
- Clean the aerator or shower head on the affected tap.
- Make sure the main stopcock and isolating valves are fully open.
- Do the water meter test for hidden leaks.
- Note whether the problem affects hot water, cold water or both.
When to call a plumber
- Your water meter moves when everything is off.
- The whole property has low pressure but your neighbours don't.
- The pressure dropped suddenly and you can hear or see water escaping.
- Only hot water is affected and cleaning the outlets didn't help.
- Your pump or backup system isn't delivering water properly.
A sudden drop with water appearing somewhere it shouldn't can mean a burst pipe. Read common causes of burst water pipes and, if water is escaping, close the main stopcock straight away.
Protecting your home from supply interruptions
If low pressure or outages in your area are a regular problem, a water backup system with storage tanks and a pump can keep water flowing to your home or business when the municipal supply drops. You can see examples in Edenvale, Bryanston and Roodepoort in our water backup projects.
Low water pressure help in Johannesburg
Badge Plumbers helps homes and businesses across Randburg, Midrand, Fourways and Sandton find and fix the cause of low water pressure, from leaks to valve and pipework problems. Contact us and tell us what you've noticed. The answers to the three questions at the top of this guide are a great start.
