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How Does a Sump Pump Work in a Crawl Space?

Residential sump pump discharging water from the end of a flexible black hose.

If you live in a home with a basement or crawlspace, one of your biggest fears may be having it flood, and rightly so. A flooded basement can ruin your floor tiles, rugs, molding and furniture. The moisture can also lead to mold, a terrible issue that can often lead to costly repairs and health issues. Not to mention it’s extremely difficult to get rid of and in many instances can be so dangerous that you will have to move out of your home while the mold is being treated. This can be especially dangerous for the very young and older individuals.

A recent study by The American Society of Home Inspectors state that 60% of U.S. homeowners have moisture issues in their basement or crawl spaces. This is an alarming number considering how dangerous this can potentially be. Those that own a home in an area that consistently gets snow or rain usually have a crawl space to prevent flooding into the basement. The thought behind this is that the water will be trapped in the subterranean crawlspace before it makes its way into your basement.

I learned how important a “working” sump pump is the hard way through no fault of my own. Years ago, I went on vacation, when I returned, I learned that the electricity went off during a rainstorm. This stopped my sump pump from working and water collected in my crawl space and up to the basement. I came home to a flooded basement and a big mess to clean up.

It was very expensive to clean up, big industrial fans were brought in to dry the basement, a new rug needed to be installed and I lost many valuables like old year books and many photo albums that were stored in the basement, never expecting to have it flood.

This is how I first learned how important a sump pump is to protect your home from flooding and excess moisture.

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Why is my Crawl Space Wet?

Sump pump manhole with water backup viewed with a flashlight.

That’s a very important question because your crawl space should never be wet! If it’s wet, you need to find out why it’s wet and get rid of the water as soon as possible to avoid potential problems.

A lot of pipes and drain lines go through a crawlspace, and on some occasions, they may begin to leak. The problem is most people don’t check their crawlspaces very frequently. When they do check the crawlspace and it’s wet, it may have been an ongoing problem that is just now being discovered.

Many common drainage and leakage problems may originate in the crawl space and basement. It’s your job to figure out how the water got there. Here are some reasons why there is water in your crawlspace and leaking into your basement.

  • Surface water that makes its way into your crawl space is often due to overflowing gutters, poor grading or leaking in the windows and cracks in the foundation.
  • When you get long periods of consistent rain, the outside soil can get saturated and push moisture through the crawlspace and basement walls, this is called hydrostatic pressure.
  • Groundwater may get into your crawl space when the foundation and soil around the foundation are oversaturated with water.
  • Leaking and bursting pipes can cause water to collect in the crawl space. This may be hard to spot by the naked eye if the crawlspace has a dirt bottom where the water can be absorbed.
  • In the basement, window wells that have been clogged or not properly installed. This may create a build-up of water that can seep into the basement and crawlspace. You should check for water stains on the walls around window wells to see if there is a sign of staining or moisture.
  • There may be issues with the foundation of the home such as cracks in the mortar or foundation walls or in the joints where the floor concrete meets the walls.
  • Heavy rains and clogged sewer lines can cause sewer backups. When heavy rains are too much for sewer systems to accommodate, sewage can start coming up through the drains.

When Do You Need a Sump Pump in a Crawl Space?

If you have any water in your crawlspace you need a sump pump. So, if you’re asking yourself, “Do I need a sump pump in my crawl space?” my guess is you do!

If you have water in your basement or crawlspace you may have a serious problem and one that needs your immediate response. Excess water can create a wide range of problems which can be very costly to repair as well as have serious health implications if not attended to promptly.

  • Moisture causes water vapor, which is responsible for rot, mold and musty, moist air that attracts dust mites, parasites that can live in bedding, carpet, and furniture, which can trigger allergic reactions. This can impact not just your home, but also the health from the air impurities you’re breathing.
  • It attracts pests, which are attracted to mold. Mold thrives on wood, paper, cardboard, and dead insects, which are usually found in crawl spaces.
  • Other pests are attracted to the moisture found in crawlspaces. Mice, rats, and snakes may decide they need a new home under your house, where it’s nice and damp, just the way they like it.
  • Elevated energy bills which are caused because damp air takes more energy to heat and cool the home than dry homes.

How to Tell If You Have a Crawl Space Leak

Replacing the old sump pump in a basement with a new one to drain the collected ground water from the sump or pit.

You never want to have a crawl space leak, but it is better to find out the leak and fix it before it causes flooding or other problems. Here are some signs that may tell you that there is a crawl space leak.

  • Does your basement or home have a musty smell? If so, this may be a sign of water damage and the growth of mold. If you find the smell getting stronger the closer you get to the crawl space or sump pit, you may have a leak and water damage.
  • If there is mold or mildew in your crawl space, that is a sign of a moisture problem caused by leakage. You should have a mold removal expert come out to find the source of the leak, repair it and treat it to prevent mold from reappearing.
  • Regularly check the crawlspace floors and walls for any sign of staining. Cracks and stains point to water damage.

Why it’s Important to Install a Sump Pump

Residential sump pump discharging water from the end of a flexible black hose.

The best time to install a sump pump is before you need it. Having a sump pump can save your home from a potential flooding disaster. A sump pump will prevent groundwater from building up in your crawl space before it has time to collect and start damaging your home.

In areas that get frequent rain and snow, it is critical to have a sump pump installed to make sure your home stays dry at all times. You need to make sure your crawlspace is dry at all times. If your crawl space stays dry, the moisture and water will not have the chance to go up into the basement and cause serious damage and a costly home repair.

How Does a Crawl Space Sump Pump Work?

A sump pump is used in basements and crawl spaces in areas where rain and snow are common. This can lead to excess moisture build-up. A sump pump job is to keep the crawl space and basement dry at all times.

Here’s How Your Homes’ Sump Pump Works

Sump pumps are a common household item and are available at most hardware or home supply stores. A sump pump is always installed at the lowest part of the crawl space in a “sump pit” a hole in the crawlspace and the lowest part of the foundation.

During rain or snowstorm, the pit starts collecting water and the pump is activated through a flotation system. The system comes on once the water reaches a certain level is drawn out of the pit through a hose that is positioned away from the house.

Without a sump pump to get rid of the water in the sump pit, the water would first collect into the crawl space, then into the basement. There’s where your real problems arise.

Unless you’re considering turning your basement into an indoor pool, you will definitely want to have a sump pump installed to protect your home from excess water.

Simple Maintenance Checks for Your Sump Pump

Maintenance check for sump pump.

There’s no reason to have a sump pump if it isn’t working properly. So, every couple of months, you should conduct a few easy maintenance checks to make sure it is working properly. This is especially important in early spring when most areas are prone to rain, and late fall in areas that get snow. If your sump pump is working, it will give you peace-of-mind going into the most critical times of the year for crawlspace and basement flooding.

Sump pump checklist:

  • Make sure the pump is upright and not leaning to one side. For it to effectively remove excess water, it should be upright.
  • Pour some water into the sump pit, this should activate the pump and remove the water. If it doesn’t, it isn’t working properly and needs to be repaired ASAP.
  • If you have a submersible pump, take it out of the pit and make sure the bottom grates are clean from buildup and small rocks and stones that can block the intake.
  • Make sure the pipes connected to your sump pump are tight and are draining a minimum of 20 feet from the foundation of your home.
  • Check the vent holes in the pump from any blockages that may not allow water to flow through to the outlet tube.

If your sump pump passes this list, it should be good to go for another season. If there is anything wrong, call in a professional as soon as you can to fix or replace your sump pump to make sure you are protected from inclement weather which could lead to flooding.

Other Ways to Protect Your Crawl Space and Keep Your Home Dry

Repairing a sump pump in a basement with a red LED light illuminating the pit and pipe work for draining ground water.

It is obvious how important it is to keep your crawlspace and basement dry and how important a sump pump is in doing so. But there are other options worth considering as well:

  • A basement waterproofing system such as those by WaterGuard® which will contain wall and floor leaks before it gets to the basement floor. It is a drainage channel system that is placed beneath the concrete. The channel has small holes that enable water to enter the drain line keeping the basement dry.
  • To prevent hydrostatic water pressure from coming through the wall/floor joints, some products reduce this problem. One product is the SealOnce Basement System It uses a hollow PVC basement to collect any water and drain it to the sump pump.
  • Lay a thick plastic vapor barrier like CrawlSeal over the floor, this will help you spot any signs of water from a plumbing leak. It is easy to use and makes seeing leaks easier than they would be than looking at the ground soil.
  • You may want to “encapsulate” your crawl space by installing a vapor barrier, which keeps the outside elements out of your crawl space. You may also want to put in an airtight door that fits around the sump pump keeping all moisture below, keeping it from your basement and home.
  • Crawl space fans can clean stale air and can help rid your home of radon, gassing of treated wood and other unpleasant smells that may permeate your home. It will work with other products to help keep your crawl space dry.
  • Dehumidifiers are also used in crawl spaces. They both dry and filter the air. Most include a water collection try that will shut off automatically when they reach water capacity, so you won’t have to empty the tray. It offers a “set-it-forget-it” process that needs little or no maintenance after installation.