Low Water Pressure in House: Causes & Solutions
Low water pressure throughout your house is more than just an inconvenience—it affects everything from your morning shower to running the washing machine. If you're experiencing poor water pressure in your home across Crawley, Horsham, Redhill, Reigate, Horley, East Grinstead, Haywards Heath, Burgess Hill, Brighton, Epsom, or anywhere in West Sussex and Surrey, this guide will help you identify the cause and find a solution.
At Mend Your Home, we solve water pressure problems for homeowners across the region every week. From simple fixes you can try yourself to professional solutions requiring our Gas Safe registered engineers, we'll cover everything you need to know.
Whether your low pressure affects the whole house or just specific taps and showers, this comprehensive guide will help you understand why it's happening and what to do about it.
Signs You Have Low Water Pressure
How do you know if your water pressure is actually low? Here are the telltale signs:
Weak Showers
Shower feels like a trickle instead of a spray. Takes forever to rinse shampoo out. Mixer showers particularly affected.
Slow-Filling Taps
Takes ages to fill the kettle, washing up bowl, or bath. Water comes out in a weak stream.
Toilet Cisterns
Toilet takes several minutes to refill after flushing. Ballvalve struggles to fill cistern.
Boiler Issues
Combi boiler struggles to heat water properly. Error codes appearing. Low flow affects boiler performance.
Appliance Problems
Washing machine or dishwasher takes much longer to fill. May show error codes or refuse to work.
Multiple Taps Running
When someone uses water elsewhere, your shower or tap flow drops dramatically. Can't run two things at once.
Common Causes of Low Water Pressure
Low water pressure can have various causes, from simple fixes to issues requiring professional attention:
1. Partially Closed Stop Tap
How common: Very common after plumbing work or accidentally turned
Affects: Whole house
Solution: Find your main stopcock (usually under kitchen sink) and ensure it's fully open—turn anti-clockwise as far as it will go.
2. Blocked or Scaled Pipes
How common: Very common in hard water areas (parts of West Sussex)
Affects: Gradual reduction over time, usually hot water more than cold
Solution: Professional descaling, pipe replacement in severe cases, or fitting water softener
3. Water Leaks
How common: Common, especially in older properties
Affects: Whole house, often with visible damp patches or high water bills
Solution: Professional leak detection and repair. Don't ignore leaks—they get worse and cause water damage.
4. Faulty Pressure Reducing Valve (PRV)
How common: Less common, only if your property has a PRV installed
Affects: Whole house, sudden onset
Solution: PRV adjustment or replacement by qualified plumber
5. Old, Corroded Pipes
How common: Common in properties 40+ years old with original pipework
Affects: Whole house, gradual worsening over years
Solution: Pipe replacement (repipe). Major work but transforms water pressure.
6. Shared Supply Problems
How common: Common in flats, terraced houses, or properties on shared supply pipes
Affects: Whole house, worse at peak times (mornings, evenings)
Solution: May need pump installation or larger supply pipe from water company
7. Low Mains Pressure in Your Area
How common: Less common but occurs in rural areas or high elevations
Affects: Always been low, neighbors also affected
Solution: Pressure pump system, accumulator tank, or contact water company
8. Clogged Aerators and Showerheads
How common: Very common, especially in hard water areas
Affects: Individual taps or showers only
Solution: Easy DIY fix—clean or replace aerators and showerheads
Low Water Pressure Problems?
Professional diagnosis and solutions across Crawley, Horsham, and West Sussex
Call: 07960 066300Open 8am-7pm, 7 days a week
DIY Fixes You Can Try First
Before calling a plumber, try these simple checks and fixes:
Quick Troubleshooting Steps:
Check the Main Stopcock
Find it (usually under kitchen sink, in downstairs toilet, or near front door) and ensure it's fully open by turning anti-clockwise as far as possible. This solves 20% of low pressure issues!
Clean Tap Aerators
Unscrew the aerator (mesh filter at tap spout), soak in vinegar for 1 hour to dissolve limescale, rinse, and refit. Do this for all affected taps.
Clean Showerheads
Remove showerhead, soak in white vinegar overnight, scrub with old toothbrush to clear blocked holes, rinse thoroughly and refit.
Check Isolation Valves
Taps and toilets have small isolation valves under them. Ensure these are fully open (turn anti-clockwise).
Ask Your Neighbors
If they're experiencing the same issue, it's a mains supply problem. Contact your water company (Southern Water for most of West Sussex).
Check for Leaks
Look for damp patches around property, check your water meter (if it's spinning when no water is being used, you have a leak), and inspect visible pipework.
Professional Solutions for Low Water Pressure
If DIY fixes don't solve your low pressure problem, here are professional solutions:
1. Pump Installation
Best for: Whole-house low pressure due to poor mains supply or shared pipes
How it works: Pump boosts mains pressure throughout your property
Benefits: Transforms water pressure permanently. Electric showers work better. Multiple taps can run simultaneously.
2. Accumulator Tank
Best for: Properties with fluctuating mains pressure
How it works: Stores pressurized water to smooth out pressure variations
Benefits: More consistent pressure. Helps combi boilers work efficiently. Relatively affordable solution.
3. Pipe Replacement (Repipe)
Best for: Old, corroded, or undersize pipes restricting flow
How it works: Replace old pipes with modern, larger diameter pipework
Benefits: Permanently solves pressure problems. Eliminates future corrosion issues. Increases property value.
4. Water Softener Installation
Best for: Hard water areas with scale buildup
How it works: Removes minerals that cause scale, preventing future blockages
Benefits: Prevents scale buildup. Better for appliances. Nicer for skin and hair. Reduces cleaning.
5. Professional Leak Detection & Repair
Best for: Suspected hidden leaks causing pressure loss
How it works: Specialist equipment locates hidden leaks, then professional repair
Benefits: Stops water waste. Prevents property damage. Reduces water bills. Restores pressure.
Specific Low Pressure Scenarios
Low Pressure in Upstairs Only
Common causes: Gravity-fed system running low, blocked pipes to upstairs, or undersized pipework
Solutions: May need pump installation, larger diameter pipes, or conversion to mains-pressure system
Low Hot Water Pressure Only
Common causes: Scaled heat exchanger in combi boiler, blocked pipes in hot water system, faulty cylinder coil
Solutions: Boiler service, descaling, powerflush, or cylinder replacement depending on system type
Low Pressure Affecting Shower Only
Common causes: Clogged showerhead, blocked shower hose, faulty shower valve, or low-pressure shower incompatible with system
Solutions: Clean/replace showerhead, replace hose, install pump for gravity-fed showers, or upgrade to electric/power shower
Low Pressure in New Build or Extension
Common causes: Undersized supply pipes, poor plumbing design, or insufficient mains capacity for larger property
Solutions: Larger supply pipe from water company mains, pressure pump system, or accumulator tank
Pressure Fine Then Suddenly Drops
Common causes: New leak, water company works in area, or faulty PRV
Solutions: Check for leaks immediately, contact water company, or have PRV inspected/replaced
How Water Pressure is Measured
Water pressure is measured in "bar" (or PSI—pounds per square inch). Here's what the numbers mean:
Very low. Barely suitable. Most appliances won't work properly. Showers unusable.
Low to adequate. Enough for basic needs but showers may be weak. Some appliances struggle.
Good pressure. Everything works well. Showers satisfying. Multiple outlets can run.
High pressure. Excellent performance. May need pressure reducer to protect appliances.
Too high. Can damage appliances, cause leaks, and waste water. Pressure reducer essential.
How to test: You can buy a pressure gauge for £10-20 that screws onto an outside tap to check your mains pressure.
Need Help with Low Water Pressure?
Professional plumbers serving Crawley, Horsham, Redhill, Reigate, Horley, East Grinstead, Haywards Heath, Burgess Hill, Brighton, Epsom, and all West Sussex & Surrey
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Frequently Asked Questions
Why is my water pressure low only in the morning?
Morning is peak usage time—everyone showering, making tea, flushing toilets. If you're on a shared supply pipe or in an area with marginal mains pressure, this demand causes noticeable drops. Solutions include accumulator tank or pump system.
Can low water pressure damage my boiler?
Low mains pressure can affect combi boiler performance and efficiency but won't directly damage it. However, if low pressure is due to a leak causing low system pressure (below 1 bar), the boiler may shut down for protection. Get it checked to avoid breakdown.
Is low water pressure my responsibility or the water company's?
Water companies are responsible for mains pressure up to your property boundary. Inside your property boundary (including your supply pipe to the house) is your responsibility. If neighbors are also affected, contact your water company.
Will cleaning my showerhead really help?
Yes! Limescale buildup in showerheads is extremely common in hard water areas across West Sussex. Soaking in vinegar overnight often dramatically improves flow. This is the easiest and cheapest fix to try first.
How much does a water pressure pump cost to install?
Pump systems vary depending on your property size and requirements. Contact us for a free, no-obligation quote. We'll assess your specific situation and recommend the most cost-effective solution for your home.