The Ultimate Guide to What Causes Low Water Pressure in Your Home and How to Fix It

There’s nothing quite like stepping into the shower—only to be greeted by a pitiful trickle instead of a powerful stream. If that sounds familiar, you’re not alone. Low water pressure is a common frustration for homeowners, and the good news? In many cases, you can fix it yourself.

This guide breaks down the why behind weak water pressure and gives you step-by-step ways to bring the flow back.

What Is Water Pressure, Anyway?

Water pressure is the force that pushes water through your home’s plumbing. It’s measured in PSI (pounds per square inch). Most homes have water pressure between 40 and 80 PSI, with 60 being the sweet spot.

If your pressure drops below 40, you’ll feel it—showers take longer, faucets don’t fill the sink like they used to, and appliances like dishwashers or washing machines struggle to perform.

Common Causes of Low Water Pressure (And What You Can Do About Them)

Let’s get into the root causes, starting with the easy-to-check and moving toward the more complex.

1. Leaks in Your Plumbing System

Even a tiny leak can siphon off enough water to lower your pressure noticeably. Leaks don’t always cause visible damage, so here’s a simple test:

• Turn off all water-using appliances and faucets.
• Check your water meter.
• Wait two hours without using water, then recheck the meter.
• If the number changed, there’s likely a leak.

Fix: For minor, visible leaks, a quick patch or clamp may help temporarily. But larger or hidden leaks? Definitely a job for a plumber.

2. Partially Closed Valve

Your home likely has two important valves:

• Main shut-off valve (usually inside or near the house)
• Water meter valve (usually outside or underground)

If either one isn’t fully open, it’ll restrict water flow.

Fix:

• Ball valve? Make sure the handle is parallel to the pipe.
• Gate valve? Turn it counterclockwise until it stops.

If your water pressure dropped after plumbing work, double-check that these valves were reopened completely.

3. Clogged or Corroded Pipes

Over time, mineral deposits, rust, and sediment can clog your pipes—especially if you have older galvanized steel ones. These clogs shrink the inner diameter, slowing water down.

Fix:

• For minor mineral buildup, try chemical treatments made for plumbing.
• If it’s corrosion, replacement may be your only safe option. It’s pricey but necessary—neglect could lead to bursting pipes and water damage.

4. Water Demand Overload

Running too many water-using appliances at once? That’ll definitely lower pressure.

Fix:

• Stagger water use.
• Run dishwashers and laundry machines at night.
• Avoid long showers during peak hours (usually morning and evening).

Bonus: Off-peak water usage might even save you a few bucks on your water bill.

5. Shared Water Lines

Live in a duplex, townhome, or closely packed neighborhood? You might share a main water line with your neighbors.

If they’re all using water at the same time—guess what? You get the leftovers.

Fix:

• Try timing your water usage around neighbors’ routines.
• For a permanent fix, you’d need your own dedicated line, which involves digging and some serious plumbing work.

6. Failing Water Pressure Regulator

This little device is meant to keep your pressure within a safe range. But when it fails, your water pressure could either skyrocket or plummet.

Symptoms: A sudden, whole-house pressure drop or erratic pressure changes.

Fix:

• Test your water with a pressure gauge (attach to an outdoor spigot).
• If it reads below 50 PSI, and the regulator is old or damaged, it’s time to replace it.
• This fix is best handled by a pro.

7. Gunked-Up Fixtures

If only one faucet or showerhead is acting up, it might not be a pressure issue—it could just be clogged with mineral buildup.

Fix:

• Unscrew the aerator or showerhead.
• Soak it in vinegar overnight to dissolve debris.
• Rinse and reinstall.

Still no improvement? Replace the fixture—many are inexpensive and easy to install.

8. Water Company Problems

Sometimes, the issue has nothing to do with your plumbing. Maintenance work or pipe breaks on the city’s end can temporarily drop your water pressure.

Fix:

• Ask your neighbors if they’re seeing the same problem.
• Contact your water company or check their website/social media for service updates.

Tip: Always ask if a boil water notice is in effect. Pressure drops can allow contaminants into your water supply.

How to Troubleshoot Water Pressure Step-by-Step

Here’s a quick sequence to help you pinpoint the issue:

1. Check if it’s just hot water – could be your water heater.
2. Test different fixtures – is it isolated or everywhere?
3. Inspect main and meter valves – make sure they’re fully open.
4. Use a pressure gauge – test PSI at an outdoor spigot.
5. Check for leaks – use the water meter method.
6. Look at the regulator – compare gauge reading to regulator setting.
7. Call the water supplier – rule out external problems.
8. If all else fails, call a plumber.

Preventing Low Water Pressure: 5 Tips for Long-Term Peace of Mind

• Clean fixtures regularly with vinegar to prevent buildup.
• Inspect pipes yearly, especially if your home is older.
• Flush your water heater to remove sediment.
• Keep an eye on PSI with a home pressure gauge.
• Schedule regular plumbing checkups, especially before buying or remodeling a home.

When to DIY vs. When to Call a Pro

DIY Is Fine For:

• Cleaning or replacing fixtures
• Opening valves
• Running a pressure test
• Coordinating water usage

Call a Pro If:

• Pipes are corroded or leaking
• Pressure regulator needs replacing
• You suspect major clogs inside walls or underground
• You need new plumbing lines or a booster pump

Final Thoughts: Keep the Flow Going

Low water pressure can be a minor annoyance or a sign of bigger plumbing issues. The trick is knowing what to check, what to fix yourself, and when to hand things over to a pro. Whether it’s a clogged aerator or a leaky pipe in your wall, the faster you act, the better off your home (and wallet) will be.

So grab that pressure gauge, check your valves, and get that water flowing again.

Call 1-Tom-Plumber 

Don’t hesitate to contact us here or call us at 1-Tom-Plumber (1-866-758-6237) if you need any plumbing, drain cleaning, water damage, or excavation service. 1-Tom-Plumber’s certified team of plumbers and drain technicians respond immediately to any emergency plumbing, drain cleaning, or water damage problem. We also handle the excavation of underground water lines and sewer main lines. Our immediate-response team is available every day and night of the year, even on holidays.