Leak Detection
Pinpoint a concealed leak in a wall, a ceiling or the buried supply line, so only the right spot gets opened.
Homeowner guide
Low Water Pressure in Louisville, CO: 8 Causes and Fixes
Start by asking where the pressure is low. One faucet points to that fixture. Every fixture points to the supply side. The answer tells you whether this is a ten-minute fix or a job for a plumber.
By the Flatirons Express Plumbing team ·
One fixture or the whole house
Run water at several taps, hot and cold. When a single fixture is weak, the trouble is local: a clogged aerator, a partly closed stop valve or a worn cartridge. If only the hot side is weak, look at the water heater and its valves.
If everything is weak, test the cold at the outdoor hose bib too. Weak flow everywhere points to the main valve, a pressure regulator, the service line or the utility.
Aerators and showerheads
Mineral deposits and sediment collect in the small screens at faucet tips and in showerheads. Unscrew the aerator, rinse it and soak it in vinegar to dissolve scale. Do the same for the showerhead.
This costs nothing and fixes more low-flow complaints than any other step. If flow stays weak after cleaning, the cartridge or the supply line may be restricted.
One fixture or the whole house
Where the pressure drops tells you where to look first.
| Where it is weak | Likely cause | First check |
|---|---|---|
| One faucet or showerhead | Clogged aerator or screen | Unscrew and rinse the part |
| Hot water only | Sediment in the heater or a partly closed valve | Check the heater's shutoff and flush it |
| Whole house | Main valve, regulator or the supply line | Open the main fully and check the regulator |
| Whole house plus a high bill | A hidden leak | Run the meter test |
Partly closed valves
The main shutoff and the fixture stops can be only partly open after a repair. Gate valves also corrode and stick halfway. Open the main valve fully and check each stop valve. Turn them gently, since old valves can break.
A main valve that will not open fully should be replaced. A stuck or leaking valve can turn small problems into emergencies.
The pressure-reducing valve
Many homes have a pressure-reducing valve near the main that lowers incoming pressure to a safe level. When it wears out, pressure can drop or swing. A gauge on a hose bib shows the actual pressure.
A plumber can test the valve, adjust it or replace it. If the valve fails high, pressure can be too strong, which damages fixtures, so low and high readings both matter.
Hidden leaks and failing pipes
A leak between the meter and the house will drop pressure at every fixture. Galvanized steel pipe that has corroded inside also restricts flow. Both are worse in older houses.
A meter test shows whether water is moving with everything off, and a leak detection visit finds the spot. If the pipe itself is the problem, repiping is the long-term fix.
Checking the pressure yourself
A simple gauge that screws onto an outdoor hose bib shows static pressure in seconds. Read it with no water running. Many homes are happiest in a moderate range, and a reading far below that, or far above it, tells you which way to look.
Compare a reading with the same gauge at different times of day. If pressure sags in the evening, when neighbors use the most water, the cause may be on the utility side rather than inside your walls.
Older pipes and mineral buildup
Galvanized steel pipe corrodes from the inside, and the opening narrows over the years until flow drops at every tap. The change is gradual, so it is easy to miss. Hard water leaves scale in fixtures and heaters as well.
If many fixtures in an older house have lost strength, the supply pipe itself may be the issue. A plumber can look at pipe material at the meter and under the house. In that case, repiping may be the lasting fix.
Stopping the problem for good
Once you find the cause, write it down. Note which fixtures were affected, what you cleaned or replaced and what the gauge read afterward. If the problem returns, that record helps a plumber skip steps you have already tried.
Keep fixture screens clean once or twice a year, test the pressure gauge reading every season and exercise the main valve. Small habits catch trouble early, and they keep minor pressure complaints from turning into a major repair.
What to tell the plumber
Say which fixtures are weak, when the problem began and whether hot and cold are both affected. Mention the gauge reading if you took one, and any recent work on the house or the street. Those details point the technician to the right spot within minutes.
If a neighbor has the same problem, mention that too. It suggests a supply issue that the utility should hear about. A call to the utility costs nothing and may solve the whole thing without a visit to your house.
Shared and older supply lines
In some neighborhoods several houses draw from one older line, and a problem at a shared section can cut pressure for everyone. Ask nearby households whether they have noticed the same change before spending money inside your own house.
A short pressure reading at the hose bib, taken at the same time each day for a week, gives you a clear picture to share with the water provider.
Utility and shared supply
If your neighbors report low pressure too, the cause may be the utility, a main break or heavy demand during a hot afternoon. Call the water provider before you pay for diagnosis.
In summer, irrigation demand can lower pressure on a block. It is a good reason to run sprinklers at off-peak hours.
Quick answers
Low water pressure questions
The showerhead may be clogged with scale, or its flow restrictor is in place. Clean or replace it.
A leak, a failed pressure regulator or a partly closed valve is likely. Check the meter and the main valve.
It can cause low hot-water flow if the valves or the pipes are restricted. Cold flow should stay normal.
A pressure gauge on a hose bib shows it. Plumbers can say what range suits your fixtures and your regulator setting.
Services that connect to this topic
Repiping & Whole-Home Pipe Replacement
Replace aging galvanized, copper or early plastic supply lines with new PEX or copper across the house.
Faucet & Sink Repair
Stop drips, restore flow, free a stuck stop valve and cure leaks under the vanity.
Keep reading
What makes pipes bang when water stops
A bang when a valve closes is water hammer. It stresses pipes and fittings, and it is usually fixable with an arrestor or a pressure check.
Choosing between PEX and copper
Both materials work. The choice comes down to freeze tolerance, access, budget and what your house already has.
Tracking down a hidden leak at home
A meter test, a toilet dye test and a walk through the basement can find most leaks before you call anyone.
Weak pressure all over the house?
Tell the dispatcher where it is weak when you call. A local contractor can check the supply side.