Your shower is a drizzle. The kitchen tap runs slow. Water trickles rather than flows. Low water pressure ruins morning showers and makes cleaning difficult.
Sometimes the problem is your water company. Sometimes it’s your pipes. Sometimes it’s one tap or the whole house. The fix depends on the cause.
Check if your area has low pressure first
Before assuming it’s your plumbing, ask your neighbours. If they have normal pressure and you don’t, the problem is yours. If they have low pressure too, the water company is the issue. You can’t fix that directly, but the company will work on it.
You can also check your water meter or stop tap. If you have very low pressure there, the feed from the street is the problem. Higher pressure inside the house points to a problem downstream.
Low pressure in one tap only
If only your shower is affected, the showerhead is clogged. Scale and mineral deposits build up inside, restricting flow. Unscrew the showerhead and soak it in white vinegar for 30 minutes. Use a small brush to clean the holes. Screw it back on. Pressure returns.
If only your kitchen tap is slow, the aerator (the screen at the tap end) is blocked. Unscrew it, clean it, and put it back. Same fix as the showerhead.
If it’s a cold tap only, there might be a blockage in the cold water pipe feeding that tap. This is less common but possible if the pipe is old and corroded. Call a plumber to check.
Low pressure in hot water only
The immersion heater or boiler is restricting flow. Sediment builds up inside the hot water tank or boiler, blocking the outlet. The tank needs flushing.
A plumber can flush the tank (cost: GBP 200-400). If the boiler is very old, replacement might be cheaper than repeated flushing.
Alternatively, the hot water feed is kinked or blocked. Call a plumber to check the pipes.
Low pressure throughout the whole house
This is usually a problem with your pipes, your water company’s supply, or your water tank level.
First, check if the water company has notified you of maintenance work. Low pressure in the area? They’re probably doing infrastructure work. It’s temporary and you can’t fix it. Contact them for updates.
Second, check your water tank if you have one (common in properties with low mains pressure). If it’s empty or nearly empty, no water flows to your taps. Refill it (usually a float switch in the tank that triggers a refill). If the float is broken, water won’t refill automatically. A plumber can fix or replace it (GBP 100-200).
Third, look for leaks. A hidden leak in underground pipes or under the house drains water, reducing pressure. Signs: wet patches outdoors, soggy ground, or a constantly running water meter even when no taps are on. Call a plumber for leak detection (usually GBP 150-300 for the diagnostic).
Fourth, check for blockages in your main feed pipe. This is rare but possible in old systems with corrosion inside the pipes. If pressure is low throughout the house and nothing else is wrong, this might be it. A plumber can pressure-test the system to confirm.
Pressure dropping suddenly
A pipe has burst or a major fitting has failed. You might see water damage, wet walls, or soggy floors. Don’t wait. Call a plumber immediately. This causes water damage and you’re wasting water every minute.
If you see no water damage, it might be a slow leak. The water meter will tell you. Turn off all taps. Note the meter reading. Wait an hour. If the meter has moved, you have a leak. Call a plumber for detection.
Low pressure at night or off-peak hours
The water company is restricting supply overnight in your area to manage demand. Nothing you can do. It’s temporary and normal in some areas during peak seasons (summer, winter). It’ll return to normal in off-peak times.
Low pressure in the shower specifically
Check your thermostatic mixing valve (TMV). Many showers have a valve that mixes hot and cold water. If the cold inlet is blocked, the valve closes to avoid scalding, and you get low flow. Clean the inlet. If that doesn’t work, the valve itself is failing. Replacement is GBP 150-300.
Also check if someone else is using water elsewhere in the house. Running the washing machine or watering the garden reduces shower pressure. This is normal and not a fault.
Professional Plumbing Services in London
Whether you’re dealing with a low-pressure shower, slow kitchen tap, restricted water flow, or low water pressure throughout your home, identifying the cause early can help prevent more serious plumbing problems. From blocked showerheads and aerators to hidden leaks, tank issues, or problems with the main water supply, understanding the possible cause makes it easier to find the right solution.
For homeowners across London, Plumr provides professional plumbing and heating services. Their experienced plumbers can investigate low water pressure, identify issues with pipework, taps, showers, tanks, and leaks, and recommend the appropriate solution based on your home’s plumbing system.
FAQs
How do I know if low pressure is my problem or the water company’s?
Ask a neighbour. If theirs is normal, it’s your pipes. If theirs is low too, it’s the water company. You can also check at your stop tap or water meter. If pressure is low there, it’s the company’s supply.
Can I fix low water pressure myself?
Yes, if it’s a clogged showerhead or aerator. Clean them as described. For anything else (leaks, tank issues, blocked main pipes), call a plumber.
What causes low hot water pressure only?
Usually sediment in the hot water tank or boiler. It restricts the outlet. A tank flush fixes it. If the boiler is very old (15+ years), replacement might be more cost-effective than repeated flushing.
How much does a plumber charge to fix low water pressure?
If it’s a simple clean (showerhead), nothing (DIY). For detection and diagnosis, GBP 100-200. For fixing (flushing the tank, replacing a valve, fixing a leak), GBP 200-600 depending on the cause.
