What Causes Low Water Pressure in a House?

Some causes of low water pressure are almost impossible to fix. If your entire neighborhood has the same low water pressure problem as you, then there’s a good chance that there’s nothing you can do at your house to fix it.

Fortunately, most causes of low water pressure can be addressed relatively easily. Finding the right trained plumber can quickly resolve your problems. In some cases, you can even fix the problem yourself.

What Causes Low Water Pressure?

Some causes of low water pressure are unfortunately out of your hands. If there is a problem with your pipes or your home fixtures, then you can fix it or find a skilled professional to help you.

On the other hand, if the problem is with the city regulation or the water supplier, then you cannot easily resolve the problem. While you can always try to convince the city or water supplier to improve their service, that’s much more difficult than just calling a plumber.

1. A Malfunctioning Pressure Regulator

While poor water pressure is inconvenient, it’s not actually dangerous. High water pressure can lead to damaged plumbing or even burst pipes. Because high water pressure is potentially dangerous, homes are built with pressure regulators.

The pressure regulator measures how high the water pressure is throughout your home. Its job is to make sure that the water pressure doesn’t get too high. If it reads that your water line flow is approaching a dangerous level, then it lowers your water pressure to keep you safe.

On the other hand, your pressure regulator can malfunction like any other tool. In some cases, it may read that your water pressure is too high even when it’s not. In those cases, it will lower your water pressure to inconveniently low levels.

You can tell if your pressure regulator is malfunctioning by using an independent water pressure reader. Attach it to a spigot outside your house and measure your water pressure. Both readings should match, or else one of them is wrong.

While either tool could be malfunctioning, if you have poor water pressure, it’s a sign that your pressure regulator is probably the tool leading you astray.

2. Overtaxed or Corroded Pipes

Even under ideal circumstances, your pipes will inevitably begin to break down over time. Depending on which materials your pipes are made of, this could happen sooner or later.

Modern homes stick to copper and other kinds of piping that last for many decades. Older homes, however, might have galvanized steel piping.

Under good circumstances, galvanized steel piping can also last up to forty years or more. Under less ideal circumstances, though, they might break down in as few as twenty years.

Make sure to ask about the piping in your home if it’s old. If your home has galvanized steel piping and the water pressure is beginning to fail, there’s a good chance your pipes have degraded.

Some situations degrade pipes faster than others. A home’s water line is built to provide a certain amount of total water. That amount is based on how many fixtures in the home use water.

If you add new fixtures to your house, they can add to the total burden on the piping system. The result can be that you’re asking for more water than the water lines are designed to provide. This overtaxes them and leads to faster breakdown, ultimately culminating in low water pressure.

3. The Main House Shutoff Valve Is Partially Closed

Your home comes with a main house shutoff valve that can be entirely open to allow maximum water pressure, or completely closed, leading to no water pressure at all.

You may have never had any reason to touch your main house shutoff valve, and may not have even been aware it existed. However, it’s possible that, at some point in the past, someone adjusted the handle of the main house shutoff valve so that it only allows in some fraction of the water it is capable of providing.

If your home has always had low water pressure, then the solution might be as easy as finding the main house shutoff valve and opening it all the way up to allow for maximum water pressure.

4. Your Neighbors Share Your Pipes

Not everyone knows this, but many homes’ water lines are actually shared with some of their neighbors. The water lines are designed to fully accommodate the water needs of both houses. But if the neighbor and you are both trying to use a lot of water at the same time, you will both suffer from low water pressure.

This can be an easy problem to diagnose; just ask your neighbors if their low water pressure matches your own. On the other hand, it can be quite difficult to resolve, since you would need to have enlarged piping installed for your homes.

5. Nothing Is Wrong With Your Pipes

If every fixture in your house that uses water is suffering from low water pressure at the same time, that’s a sign that there’s a system-wide problem with your piping. Maybe the pipes are damaged, or the city or the water supplier is failing in some way.

On the other hand, what if most of your fixtures are working just fine and receiving great water pressure? If only one or a few of your figures are suffering from low water pressure, then it’s possible that the fixtures themselves are the problem, not your water pressure.

Don’t Let Your House Suffer From Low Water Pressure

We hope you learned something helpful about some of the most common causes of low water pressure and what you can do if they happen to you. If you need to learn more about keeping your water systems running smoothly and where you can find skilled professionals to help you, check out our other pages.