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All About Sump Pumps: We Answer Your Biggest Questions on This Water Removal System

At HomeLight, our vision is a world where every real estate transaction is simple, certain, and satisfying. Therefore, we promote strict editorial integrity in each of our posts.

Water damage is a major issue for homeowners that can severely affect the value of their property. 60% of homes in the U.S. experience either flooding or excessive moisture in the basement. If you’ve got pooling water under your house or live in an area that experiences floods, you most likely need a sump pump — a motor that transfers water away from your home and protects below-grade spaces from water damage.

If this is a new concept for you, you’ve come to the right place. We consulted an expert plumber to create this sump pump primer, covering purpose, installation, price, maintenance, and necessity. To help you out, HomeLight consulted with an expert plumber and crafted this helpful article that answers the most important sump pump questions you might have.

An image of a sump pump under a house.
Source: (The EnergySmart Academy / Flickr)

What is a sump pump?

Steve Stalcup, a plumber and licensed contractor from Vacaville, CA, who has more than 40 years of experience handling residential and commercial plumbing projects, defines a sump pump as “a mechanical device operated on electricity and placed where water collects that evacuates the water from your property.”

Because water flows downhill, it tends to collect at the lowest point of your home. To install a sump pump, you first dig a basin at this point (called a sump) and then place the pump inside of it. Once installed, the sump pump will collect water and transfer it to storm drainage or an area away from the property.

How can I tell if I need a sump pump?

An unmistakable sign that you need a sump pump is if water is visibly pooling at a low point in your home. If your home doesn’t have a concrete basement, you might notice that your crawl space is muddy with standing water collecting in various places.

While you might not immediately feel concerned about a small puddle in your basement, it’s an issue that you should take care of right away. Stalcup shares that “standing water can cause deterioration of your foundation, damage personal property, encourage mold, and rot any wood that it touches.”

What kind of sump pump should I buy?

There are several types of sump pumps. For instance, some sump pumps run continuously, while others are specially designed to handle sewage or pond water. For residential uses, there are two main types of sump pumps to choose from:

  • Submersible sump pump: These pumps are placed at the bottom of a sump and have their motors housed in a waterproof enclosure. Submersibles require a larger sump basin and are typically more powerful, with greater horsepower and gallons per hour ratings. Because cool water surrounds the motor, these pumps can run for more extended periods without overheating. Submersibles also make less noise, thanks to the insulating layer.
  • Pedestal sump pump: These pumps are on a long pedestal with the motor on top and a small impeller and discharge unit on the bottom. Pedestal pumps are generally cheaper than submersibles and, because the bulk of the pump is on top, you won’t need as large of a sump basin. However, in addition to being weaker and louder, pedestal pumps are also less able to handle any solids in the water they’re pumping.

Does switch type matter?

In addition to the type of pump, you can choose between a few different activation switches. These switches monitor the water level in your sump basin and activate the pump when the water reaches a certain height. Options include:

  • Tethered float: Much like the float in your toilet, a tethered float is a bulb attached by an arm to your sump pump that lifts as the water in your sump basin fills. When it reaches a certain height, it will flip a switch that turns on your pump. After it drops, the pump will cease. Tethered floats offer an extensive range of motion, meaning that the motor will have a longer cool-off period between active cycles. However, they take up more space than other options.
  • Vertical float: A vertical float is like a tethered float that is attached directly to the sump pump, usually to the rod section of a pedestal pump. While tethered floats are suitable for narrow spaces, they have a limited range of motion, and minerals or debris can sometimes interfere with their operation.
  • Electronic switch: An electronic sump pump switch is a set of sensors placed on the top and bottom of your pump that detect water and turn the motor off and on depending on which sensor is triggered. As with vertical floats, mineral buildup can affect the operation of these switches. However, debris won’t affect their functioning, and they can also incorporate water depth alarms.
  • Diaphragm switch: Diaphragm switches rely on water pressure to activate and are a good solution for submersible sump pumps that don’t have space for a tethered float. You can’t adjust these switches, so it’s critical to make sure you get the correct switch to maintain the water level of your particular basin.
An image of a construction worker installing a sump pump under a house.
Source: (Shopify Partners / Burst)

How much does it cost to purchase and install a sump pump?

The average cost of a sump pump capable of removing 1,800 to 2,200 gallons per hour is around $250, but if you live in an area that sees extreme flooding, costs can reach as high as $400 for heavy-duty pumps.

After you’ve bought the pump, you’ll need to install it. Average installation costs range from $639 to $1,938. Stalcup tells us that costs vary widely depending on the situation:

“If it’s a difficult installation — if you need to dig the hole, pour concrete, or level your floors. It’s going to cost you more than it would to simply hook up a pump and get it running.”

Because installation prices are so variable, the best way to gauge costs for your home is to get an estimate from a local plumber. Remember to tell them what kind of flooring you have, what type of pump you want, where you want the pump installed, and any other information that could affect the difficulty of your installation.

How do I keep my sump pump running smoothly?

Once you’ve got your sump pump installed, you still need to perform regular maintenance to ensure that it’s working correctly. Stalcup advises performing routine maintenance on your sump pump at least once a year. To do so, follow these steps:

  • Clean the sump basin: Make sure your sump basin is free of dirt and debris. Clear out any small items that could interfere with the pump and, if the water is dirty, fill up the basin with clean water until the pump activates.
  • Monitor the “check” valve: Ensure the check valve is pointing toward the sump pump.
  • Clean the weep hole: Your sump pump may have a small hole to release pressure between the motor and check valve. Take a small object like a clothespin and make sure the weep hole is clear.
  • Clean out the impeller: Your sump pump’s impeller is a filter fitted where the pump intakes water. These filters protect the pump from large debris but can sometimes get clogged. To unclog an impeller, simply scrub it down.
  • Check the power: Finally, ensure that there’s power running to your sump pump by inspecting the power cable and running the pump. To run the pump, all you need to do is fill your sump basin with clean water.

Do I need a backup sump pump?

So, what happens when the flooding that your sump pump is meant to combat causes the power to go out? In these situations, your home is likely to suffer water damage without a backup plan. Prepare for the worst with one of these sump pump backups:

  • Battery backup: A battery backup is a rechargeable battery that you attach to your existing pump that will provide power during a blackout. Many newer sump pump models are sold with a battery backup system already built-in.
  • Backup pump: You can also opt to install a second sump pump that relies on battery power. A secondary sump pump will take up more space and probably cost you more money. However, if your primary pump malfunctions or isn’t able to keep up with flooding, you’ll thank yourself for having it.
  • Water-powered backup: You can also choose to go with a water-powered pump that uses your home’s water pressure to create a vacuum that moves water out of your home. These pumps require no electrical power at all but aren’t capable of pumping as much water and won’t work if your property uses well water.

Is a sump pump really necessary?

When all is said and done, whether or not you buy and install a sump pump is up to you. However, water damage is a serious issue, and the typical basement flood costs anywhere from $3,000 to $10,000 to repair, well over the average price of installing a sump pump. Furthermore, adding one only increases the value of your home. So, if you think there’s a chance of flooding or water accumulation in your house, it’s probably a good idea.

Header Image Source: (Lost_in_the_Midwest / Shutterstock)