If you have ever struggled to rinse the shampoo out of your hair, washed your hands under a trickle of water, or been forced to wait for your washing machine to complete a cycle, then you have experienced the nuisance of low water pressure. Low water pressure can turn a simple task into a hassle, but once you identify the cause, either the necessary plumbing fix or a water booster pump can drastically improve your water pressure. In this article, you can learn about nine common causes of low water pressure and how to resolve low water pressure in your home.
Quick answer: If only one faucet or shower is weak, the problem is usually a clogged aerator, showerhead or fixture valve. If the whole house has low pressure, check that the main shutoff valve is fully open, test your pressure with a gauge (40 to 60 psi is normal), and look at your pressure regulator, pipes and water treatment equipment. On a well, the pressure switch and tank are the usual suspects. If your supply pressure is simply low, a booster pump is the fix.
How do you know if you have low water pressure?Testing your home’s water with a pressure gauge is the easiest way to find out if you have low water pressure. Pressure gauges are simple and inexpensive, and once installed, will allow you to check your water pressure with a quick glance.
If your water is from a municipal water supply, select an outdoor faucet near where the main water line enters your home. If your water is from a well, select a faucet that is close to the well’s pressure tank. Attach the pressure gauge to the faucet and tighten it. To get an accurate reading, make sure water isn’t being used anywhere else inside or outside the house, and then fully turn the faucet on. Once the faucet is on, you can read the water pressure on the gauge’s dial. Typical home water pressure is between 40 and 60 psi, so if the dial reads less than 40 psi, you have low water pressure.
Learn more: What is a pressure gauge and how does it work?
Do water booster pumps increase water pressure?A water booster pump is a centrifugal pump that improves low water pressure and increases water flow. Much like how a fan’s blades create a gust of air, a water booster pump’s rotating impeller draws water in and then pushes it out with increased force. This force raises the water pressure in a system. A water booster pump is installed where the main water line enters your home, so water pressure is improved in every tap and appliance.
Learn more: What is a water booster pump and how does it work?
Start here: one fixture or the whole house?| What you notice | Most likely cause | Where to start |
|---|---|---|
| One faucet or shower is weak | Clogged aerator, showerhead or cartridge | Clean or replace the fixture parts. See our shower pressure guide. |
| Only hot water is weak | Water heater sediment or a partly closed valve | Flush the water heater and check its valves |
| Whole house is weak on city water | Shutoff valve, pressure regulator, leak or low city pressure | Test with a gauge, then check causes 2 through 5 below |
| Whole house is weak on well water | Pressure switch, pressure tank, pump or clogged pipes | See “How to increase well water pressure” below |
| Pressure dropped after adding a filter or softener | Undersized or clogged equipment | Check filter cartridges and equipment sizing (cause 9) |
| Upstairs is weaker than downstairs | Elevation (gravity) | A booster pump (cause 7) |
Low water pressure is caused by a variety of issues, such as pipe corrosion, scale, leaks, and even the effect of gravity.
1. Hard water
If you have hard water, scale can accumulate in your pipes, restrict the water flow, and reduce your water pressure. Hard water has a high mineral content, specifically calcium and magnesium, and scale forms when these minerals come out of the water and stick to pipe walls, especially when the water is heated.
The solution: When scale buildup is severe enough to restrict water flow and reduce water pressure, the most reliable fix is often replacing the affected pipes. Products like CLR Calcium, Lime, and Rust remover can diminish scale, but as the scale comes off it may clog your pipes, creating another costly plumbing problem. Not to mention, it is never a good idea to put harsh chemicals in the pipes that supply your drinking water. To prevent scale in the future, we recommend installing a water softener.
Learn more: How to prevent limescale buildup in your home
2. The main water shutoff valve isn’t fully open
If your water pressure has suddenly decreased and you recently had a repair done, make sure the main water shut off valve is fully open. Most plumbing repairs require the water to be shut off, but if the valve is not completely opened afterward, your water pressure will be restricted.
The solution: Locate your main shut off valve, which is installed where the main water line enters your home, and fully open it by turning it counterclockwise.
3. A municipal water problem
Low water pressure may not have to do with your own plumbing system. Just like your home’s water supply, the municipal water supply is subject to problems that can cause low water pressure, such as leaks and corrosion.
The solution: Call the municipal water supply to report your low water pressure. Your input may alert them to the problem and will ensure your water pressure is restored as quickly as possible.
4. Faulty pressure regulator
A pressure regulator is a valve that reduces incoming water pressure as water flows into your home from the main service line. High water pressure can damage pipes and plumbing fixtures, so a pressure regulator is installed to protect your home plumbing system. Most are set to 50 pounds per square inch (psi), but if yours is set lower, your water pressure will feel low. If your pressure regulator is set to 50 psi but your pressure still feels low, it may be broken or clogged.
The solution: Adjust your pressure regulator’s setting to 50 psi if it is currently set lower. If your pressure regulator is faulty, ask a plumber to replace it.
Learn more: What is a water pressure regulator and how does it work?
5. A leak
A leak can reduce water flow and water pressure. To check for a leak, turn off all the faucets and water-using appliances inside and outside of your home, then write down your water meter reading. Check it again about an hour later. If the reading has changed, you likely have a leak.
The solution: Enlist the help of a licensed plumber to locate and repair the leak. Once the repairs are complete, your water pressure should return to normal.
Learn more: 5 advantages of owning a smart leak detection system
6. Corroded pipes
Corrosion is a natural process that occurs when the oxygen in water reacts with metal. For example, rust is a form of corrosion. When corrosion builds up in a pipe and restricts water flow, it causes low water pressure. This buildup is gradual, so the older your pipes are, the higher the risk of corrosion. While corrosion is more common in older pipes, it can also be exacerbated by acidic water. If you notice your water is tinted brown or red and has a metallic taste, your pipes may be corroded, but it is always best to consult a plumber to be sure.
The solution: Unfortunately, the only solution for corroded pipes is to have your pipes replaced. Once new pipes are installed, you should notice an improvement in your water pressure.
Learn more: What is acidic water and how do you treat it?
7. Gravity
Water contends with the force of gravity as it travels upwards. The higher the elevation water must flow, the lower the water pressure will be. Homes with multiple stories, apartment buildings, and skyscrapers may experience low water pressure due to gravity.
The solution: Install a water booster pump. Water booster pumps both improve low water pressure and increase water flow.
Learn more: What is a water booster pump and how does it work?
8. Distance from a water source
Distance from the municipal water source may affect your water pressure. The farther your home is from the water source, the farther water will have to travel through the service line, resulting in less water flow and low water pressure.
The solution: A water booster pump will increase water flow and water pressure.
9. Additional water treatment systems
Water treatment systems provide protection against contaminants and improve bad tastes and odors. They also help prevent issues that cause low water pressure, such as corrosion, scale, and dirt and debris, but if not sized properly, can contribute to low water pressure.
The solution: Make sure the water treatment equipment is sized properly, so as not to create a large pressure drop or flow loss. If needed, supplement your water treatment system with a booster pump to improve your water pressure. Keep in mind that the pump should be positioned so it increases water pressure in your home but does not force water into the filters at a higher psi, as this can damage the filtration system.
Learn more: How do water filters work?
There are three basic steps you can take to increase water pressure from a well: adjust your tank’s pressure switch, rid your pipes of debris, or install a constant pressure system.
1. Adjust your pressure switch
Test your water pressure with a pressure gauge. If the reading is below 40 psi, you may be able to raise it at the pressure switch, which sits on the pipe near your pressure tank. Most switches are set to 30/50 psi (pump turns on at 30 and off at 50) or 40/60 psi, and many homeowners move from 30/50 to 40/60 for stronger pressure. Always turn off power to the pump first, and don’t go above what your switch, pump and tank are rated for. After changing the cut-in pressure, set the tank’s air pre-charge to 2 psi below the new cut-in, measured with the tank empty. Also, having a properly sized pressure tank is integral to the success of a well system and maintaining your preferred water pressure.
Learn more: How to check your well tank’s pressure | How to Size a Well Pressure Tank
2. Examine your pipes
Sediment and minerals often build up in a well system’s pipes, which can clog, reducing water flow and decreasing water pressure. We recommend having a licensed plumber inspect your pipes and clear any obstructions to restore your water pressure.
3. Install a constant pressure system
By replacing a standard pressure tank and switch with a constant pressure system, you ensure stable water pressure throughout your home, regardless of how many faucets are running at one time. In a constant pressure system, pump speed will increase or decrease relative to the demand of water. When water demand is high, the pump speed increases, and when water demand is low, the pump speed decreases. A constant pressure system is an investment that will allow you to efficiently maintain your home’s water pressure.
Variable Frequency Drive (VFD) constant pressure systems run electronically and offer consistent pressure comparable to a city water supply. However, they are expensive and can be difficult to install.
Low water pressure FAQsWhat is normal water pressure for a house?
Most homes run between 40 and 60 psi. Below 40 psi usually feels weak, and above 80 psi is too high and can damage plumbing, so a pressure regulator is recommended.
Can a water filter or softener cause low water pressure?
Yes. A clogged filter cartridge or an undersized filter or softener can restrict flow. Replace cartridges on schedule and make sure your equipment is sized for your home’s flow rate.
Why did my water pressure suddenly drop?
A sudden drop is often caused by a partly closed shutoff valve after a repair, a failing pressure regulator, a leak, a problem with the city supply, or, on a well, a pump or pressure switch issue.
We would love to help you find the right water pressure solution for your home. If you have any further questions regarding the causes of low water pressure or how you can improve it, please do not hesitate to contact us.
