What Causes Low Water Pressure in the House?

Few household problems are more frustrating than low water pressure. It can turn a relaxing shower into a trickle and a simple task like washing the dishes into a time-consuming chore. Uncovering the reasons behind this dilemma is critical to finding effective solutions and restoring water flow to optimal conditions. In this article guide, we'll reveal the signs of low water pressure, break down possible causes, discuss solutions, understand average home water pressure, and highlight the importance of maintaining this basic element for the smooth running of your home.

How to Identify Low Water Pressure?

Most of the time, identifying low water pressure is very easy because it happens suddenly. However, in some cases, water pressure can slowly decrease over time, thereby going unnoticed or causing homeowners to feel like they are fooling themselves into thinking there is a problem. However, for most homes, there is an easy way to test the water pressure using a test gauge.

A test gauge is a simple device that connects directly to a hose spigot on the exterior of your home. After screwing the test gauge onto the socket, open the valve and check the reading. This will indicate the current water pressure at the hose connection, which is usually enough to confirm a water pressure issue in the home. If you want to make sure you have a water pressure problem throughout the house and not just one fixture, then you can connect a pressure gauge to the laundry sink and repeat the process.

There is another use for this gauge. Users can locate leaks within the system by installing a pressure gauge, closing all valves and turning off water-using appliances such as ice machines, dishwashers, and washing machines, and turning off the home's main water valve. If the pressure persists for an hour or so, the house's pipes probably don't have a leak. If it drops more than about 3 PSI, you may have a leak.

Reasons for Low Water Pressure in Your Home

There are many reasons why a home's water pressure can drop, whether it's a sudden drop or over time. Listed below are some of the most common causes of low water pressure in your home.

1. Using Too Many Water Utensils At One Time

It is common for multiple water appliances or fixtures to be used at the same time. This could be any combination of washing dishes, doing laundry, showering, watering the lawn, using the sink, filling the tub, or even pressure washing the patio or deck. The more devices that use water at the same time, the less water is needed for all applications.

Running one or two faucets at the same time is not enough to affect water pressure, but the easiest way to solve the problem is to stagger your household's water needs throughout the day. Plan to do the dishes before work, then go home, take a hot shower, prepare dinner, and and put a load of laundry on.

2. Water Main Break

If there is a sudden drop in water pressure throughout your house, you may have a burst water main in your system. This often happens during cold weather or when older systems need to be upgraded. It could cause flooding of streets and yards closest to the break, or it could take a while for municipalities to find it. Regardless, chances are the water pressure is low throughout the neighborhood, so ask your neighbors.

3. Well Failure

Many folks whose homes are on wells are in constant fear of them failing, and that’s because they very well can. If the water pressure in the home drops, the well pump may not operate. This could be because of a tripped circuit breaker, motor failure, or the aquifer itself is drying up.

4. Main Valve Is Partially Closed

The main water shutoff valve is responsible for controlling the flow of water into your home. If the valve is partially closed, it means the water pressure is decreasing. This valve is usually located on the main water pipe after it enters the home.

Depending on the type of valve, you may see a ball valve with a lever that moves 90 degrees or a gate valve with a handle that rotates to open and close the valve. To open the ball valve, simply move the handle so that it lines up with the water pipe. To fully open the gate valve, turn it counterclockwise until it cannot turn any further, then turn it back a quarter turn to avoid potential leaks or valve sticking.

5. The Water Meter Valve is not Fully Opened

The main valve isn't the only valve that affects water pressure throughout your home. In many houses, there is a water meter behind the main valve. It is used by local utility companies to measure household water consumption. Generally, a water meter isolation valve is installed behind the water meter. If the water meter valve is partially closed, the flow of water into your home will be restricted.

Check whether the water meter valve is a ball valve with a lever that moves 90 degrees, or a gate valve with a handle that rotates like a wheel. Turn the handle so it is aligned with the water pipe and open the ball valve. For gate valves, turn the valve counterclockwise until it stops, then turn back about a quarter turn to avoid leaks or a stuck valve. Take this opportunity to check that the main valve is also fully open.

6. Failing Pressure Regulator

While high water pressure may seem like a good thing, if the water pressure is too high, it can damage faucets, shower heads, appliances, and water pipes. With this in mind, homes located in areas with high water pressure often have a pressure regulator installed immediately after the main shutoff valve.

If the pressure regulator is not set correctly, it may restrict water flow excessively. You can adjust it yourself or contact a plumber to adjust it for you. However, if the pressure regulator is set to approximately 50 psi but the water pressure throughout the home is lower than this setting, it may indicate a faulty pressure regulator. Contact a plumber to replace the faulty regulator and restore normal water pressure to your home.

7. Faulty Plumbing Fixtures

If low water pressure only seems to affect one or two fixtures, there may be an isolated cause of the condition.

Aerators on faucet fixtures are designed to reduce water volume without changing pressure, but dirt, rust, and limestone can build up inside the aerator, causing the unit to restrict water flow. Likewise, shower heads can become clogged with debris (If your shower head is clogged, we recommend reading the article "How to keep the shower head from clogging when taking a shower"), or even your dishwasher's water inlet hose can become clogged.

If the fixture is relatively new, consider removing and cleaning the fixture and then reinstalling it to correct the problem. If the problem is caused by an older appliance, it may be time to upgrade to a new appliance to resolve the low water pressure issue.

8. Water Supply Problem

In some cases, low water pressure may be caused by your water supplier. If your home is connected to a municipal water system, contact your local water supplier to determine the cause of low water pressure. If they are fixing the issue, then you will need to wait for the issue to be resolved.

If you have a well system, water supply issues are a greater concern and may mean that the well pump may not operate. This can be caused by a mechanical problem, such as a motor failure or a tripped circuit breaker, but it can also happen if the well is dry. Contact a plumber who specializes in water well systems to evaluate the situation and recommend the best course of action.

9. Corrosion or Blockage of Water Pipes

If water pipes are severely corroded or clogged with scale, they can restrict water flow and cause low water pressure.

Generally speaking, galvanized steel wire will begin to corrode in about 20 years. Copper pipes have a lifespan of over 50 years, while brass pipes have a lifespan of about 40 to 70 years. If your home's water pipes are nearing the end of their life, it may be time to replace them before they start leaking.

In hard water areas, the buildup of scale and other minerals can be a bigger problem. With the extensive network of pipes throughout the home, this is not a problem that can be easily solved. Contact a plumber to inspect and possibly replace the water pipes. Also, consider investing in a water softener to help prevent this problem in the future.

10. Shared Water Supply Lines

Although rare, there are cases where the water pipes flowing into a home are shared with one or more neighboring properties. So if your neighbor takes a shower, washes their car, or puts out a lot of dishes, this will affect the water pressure in your home and any other connected homes. This doesn't mean you pay for their water, but it does mean the water supply is distributed to multiple households.

The most affordable option to solve this problem is to plan water usage according to your neighbor's schedule, but this is not a reasonable solution. Unfortunately, another way to solve this problem is to have a plumber replace the water pipe from the municipal service to the home, ensuring the new pipe only leads to your home, although replacing the pipes can be a costly undertaking.

11. The Branch Line is Too Small

Some homes have normal water pressure, but are restricted by narrow branch lines as water is distributed to appliances and plumbing fixtures. A branch line is a pipe that exits from the main water main after it enters the home.

If you suspect this is the cause of your low water pressure problem, contact a plumber to evaluate your plumbing system. They will be able to determine if the branch line is too small for the current network of electrical and plumbing fixtures. If the pipes are too small, then the plumber may recommend upgrading the pipes to a larger size to solve the problem.

12. The Filter of the Bubbler or Shower Head is Clogged

There are small screens in sink aerators and shower head fixtures that collect sediment while effectively dispersing water. If there is a lot of sediment in the water, these filters will close completely, reducing the water pressure to almost zero.

Sediment can also clog toilet fill valves. Although there is no barrier, buildup can restrict water flow and prevent the toilet from filling effectively.

How to Fix Low Water Pressure Problems

Fixing low water pressure problems can be simple and inexpensive, or complex and expensive. Here are some of the most common ways to fix low water pressure.

1. Call the City

Water pressure may be low due to city conditions. Whether it's a water main break, a fire hydrant flush, or a system shut down for repairs, the city should be able to explain whether the problem is theirs or yours.

2. Open or Replace Valve

If any valves are throttled, it's a good idea to open them. This will allow more water to flow through the valve, ultimately increasing the pressure on your sink, shower, toilet, or appliance.

If the valve is completely closed, it's a good idea to find out exactly what the valve does before opening it. This helps avoid flooding or damaging your home.
If a valve is leaking or damaged, it is important to have it repaired as soon as possible. The valve may cause flow restriction, but if internal parts become loose, it may clog the entire system.

3. Clean Aerator and Filter

Another way to fix low water pressure is to clean the filters inside your sink aerator and shower head. Simply unscrew the aerator from the shower head, remove the rubber gasket with a pick, and tip the screen out onto a paper towel. Use a stiff brush to remove any buildup from the grid before reassembling.
When it comes to toilet fill valves, it's better to replace them rather than clean them. They are easy to process and cheap, so there is no point in cleaning them frequently.

4. Adjust the Regulator

For DIY enthusiasts, adjusting the water pressure regulator is no problem. These devices usually have an adjustable diaphragm that the user can adjust using a bolt on the top of the device. Turning the bolt clockwise increases the water pressure, turning the bolt counterclockwise decreases the water pressure. If you suspect there is a problem with your regulator, it's best to call a professional.

5. Fix Bugs

If any pipes leak, it is important to repair them immediately. Leaking pipes not only disrupt water pressure but can also lead to mold and pest problems. Check appliances, hoses, valves and other fixtures for leaks.

What is the Average Household Water Pressure?

House water pressure refers to the pressure at which water is carried through your plumbing fixtures. The standard unit of measurement is pounds per square inch (psi). Typically, residential water pressure ranges from 40 to 80 psi, with 60 psi considered optimal. This range ensures efficient water flow without stressing pipe components.

The Importance of Maintaining Optimal Water Pressure

1. Efficient equipment functionality：

Equipment such as washing machines and dishwashers operate optimally within a specific pressure range. Maintaining proper water pressure ensures these devices operate efficiently, resulting in cleaner clothes and dishes.

2. Consistent Shower Performance:

Adequate water pressure in the shower enhances the overall bathing experience, ensuring a steady and vibrant flow of water. If the water pressure in your shower is too low, you can refer to the article "How to increase the water pressure in your shower?" for more solutions.

3. Prevent Plumbing Problems:

Excessive water pressure can stress pipes, joints, and fixtures, causing leaks, bursts, or premature wear. Maintaining optimal pressure can help prevent these types of plumbing problems, saving homeowners from costly repairs.

In summary, there are many causes of low water pressure, and solving low water pressure issues requires a systematic approach, from identifying the root cause to implementing effective solutions. Regular maintenance and timely repairs play a key role in ensuring your home enjoys optimal water pressure, enhanced functionality and comfort.

Common FAQ about Low Water Pressure

Q: Can a water pressure booster help solve the problem of low water pressure?
A: Yes, if your home regularly suffers from low water pressure, a water pressure booster pump can help. It is installed in your water line and increases the pressure of the water entering your house. However, before considering a water pressure booster pump, it is important to first identify and resolve any potential issues.

Q: When should I call a plumber?
A: If you've tried basic troubleshooting and your water pressure is still low, or you've discovered a more complex problem like a leaking or clogged pipe, it's time to call a professional plumber. Plumbers can more accurately diagnose and fix problems, ensuring your plumbing system is functioning optimally.

Q: Why is the water pressure low throughout my house?
A: Low water pressure throughout the house can be caused by municipal water supply issues, such as maintenance or infrastructure issues, or home-specific issues such as a partially closed main valve, clogged pipes, or even a leak in the duct system.

Q: What exactly causes low shower water pressure?
A: Low water pressure in the shower can be caused by a clogged shower head, faulty bathroom plumbing, or a specific issue with your hot water supply, especially if you have a water heater with sediment buildup.

Q: Will blocked pipes affect water pressure?
A: Yes, mineral deposits, rust, and debris can build up over time, clogging pipes and significantly reducing water flow and pressure.

Q: How to check whether the piping system is leaking?
A: Look for obvious signs of water damage, listen to water running when all faucets are turned off, and monitor water meter usage when water is not being used. Any of these could indicate a leak.

Q: Is it possible that only one faucet has low water pressure?
A: Of course. If only one faucet has low pressure, the problem may be localized, such as a clogged aerator or a specific issue with that faucet's supply line.

Q: How do you increase the water pressure in your home or shower?
A: Start by checking and cleaning any clogged aerator or shower head. Make sure all valves, including the main water valve, are fully open. If the problem persists, you may need to consult a plumber, as the cause may be more complicated.

Q: Does the age of a home affect water pressure?
A: Older homes may have outdated plumbing that can cause water pressure issues, including corroded pipes or outdated fixtures that don’t meet modern water flow standards.

Q: Will a water heater failure reduce water pressure?
A: Yes, especially for hot water pipes. The buildup of sediment in the tank can reduce efficiency and water flow, which can affect pressure.

Q: How will municipal water supply work affect household water pressure?
A: Municipal water supply maintenance, repairs and infrastructure upgrades may cause temporary reductions in water pressure. Additionally, living at a higher altitude than the source of supply naturally results in lower stress.

Q: Is there a quick fix for low water pressure in the shower?
A: Cleaning or replacing your shower head is a quick fix. For immediate improvement, remove the flow restrictor inside the shower head, although this may increase water consumption.

Q: How often should your plumbing system be inspected to avoid low water pressure?
A: It’s best to have your plumbing system inspected by a professional every two years to prevent problems that could cause low water pressure.

Q: What effect does a water softener have on water pressure?
A: If your water softener is clogged with minerals, it can sometimes reduce water pressure. Regular maintenance is essential to prevent this.

Q: Will the water pressure be low if the main water valve is not fully opened?
A: Yes, if the main water valve is not fully open, it will restrict the flow of water into your home, resulting in lower pressure.

Q: What is a water booster and when should it be used?
A: A water pressure booster is a pump installed in a water supply system to increase water pressure. It is particularly useful for homes that experience persistent low water pressure due to municipal water supply issues or external factors such as altitude.

Q: How can I tell if my water pressure problem is caused by the municipal water supply or my home's pipes?
A: Check with your neighbors to see if they are experiencing similar problems. If so, the problem may be with municipal supplies. If not, the problem may be unique to your home's plumbing.