Your crawl space is a small, unoccupied area between the ground and your home. It offers a buffer between the ground floor of your house and the earth beneath you, giving you an extra layer of insulation and providing additional support to your living areas.
This exposed area can suffer from excessive moisture, and this water, if left unchecked, can cause damage to your home. A crawl space sump pump can help and, in this guide, we’ll explain everything you need to know about crawl space pump installation so you can learn how to do it in your home.
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Why Would You Need a Crawl Space Sump Pump?
Crawl space sump pumps might be new to some people, and you may be wondering why you should spend time and effort installing one. There are a few key reasons that homeowners benefit from having a sump pump:
Water In Your Crawl Space
If there's water in your crawl space, then you've probably got an issue. Even a small amount of water in your crawl space can cause severe damage to your home, causing issues with your foundations and plumbing which are expensive to repair. A crawl space sump pump can remove the excess groundwater and help to protect your home.
Low Lying Home
The amount of water in the ground is influenced by the water table. If your home is in a low-lying area below the water table, then the ground is more likely to be saturated, and you need a crawl space sump pump to help you manage it. You'll have a similar issue if you live below sea level or if you live in a swampy area.
Snowy Or Rainy Areas
You also need to consider the environment you live in because, unfortunately, homeowners who live in wet climates need to take extra precautions. Snow and rain can seep into the crawl space beneath your home and start to cause damage. You’ll need a crawl space sump pump to help remove the extra moisture caused by the weather.
How To Install A Sump Pump In A Crawl Space: Step-by-Step Guide
Tools & Supplies Required
It’s important to have all the appropriate tools to do this job properly. It’s not overly complicated, but make sure you have all of these before you start:
Step By Step Instructions
Installing a sump pump in your crawl space is a relatively easy job, and you should expect it to take 1-2 days to complete everything. You should be able to do this on your own without help, but if you don't feel comfortable, you should consult a professional. Paying a small amount upfront can save you a fortune in the long run.
Once you've gathered all your tools, you should follow these steps:
- 1Prepare The Crawl Space
Start by accessing your crawl space to remove any debris or other items which could impede you. You might have trash or old lumber down there, so make sure it’s all kept completely clear so your sump pump can work properly.
- 2Decide On The Location
While clearing out the space, you need to decide where your sump pump and basin will go. It’s up to you where you place it, but we recommend putting it in the lowest part of your crawl space so that the water naturally drains to that point.
- 3Dig The Basin Hole
You should now dig a hole that is big enough for your basin. Sump basin sizes vary, but they will typically be 30 inches deep and 18-24 inches across. You need to leave a few extra inches for the aggregate rock placement, which will go in the base and around the hole's edges and will hold the sump basin in place. During this step, you need to make sure you don't disturb the foundations or any of the earth near to it. If the foundations are undermined, it can cause structural damage and even destabilize your whole home. When doing this structural work, you should make sure you keep well clear of the foundations.
- 4Prepare The Sump Basin
Most sump basins will come fully prepped, so there's not much to do. However, if your basin doesn't come with pre-drilled holes in the sides, then it’s worth adding some in here. This will allow the water to drain through the ground directly into the basin and help keep the crawl space dry. You should also take this opportunity to check that your sump basin will fit into the crawl space. Some are very narrow, and to get them to the hole, you may need to disassemble them into two parts. This is usually straightforward, but you should look at the specific instructions for your basin.
- 5Install The Sump Basin
Ensure there are several inches of drainage aggregate (river rock works best) at the bottom of the sump hole. The finer the rock you use, the better the water will drain, but very small rocks can cause blockages in your sump pump. Once you have your drainage aggregate, place your sump basin on top of it. Once it's securely in place, you should fill up the remaining gaps with extra drainage aggregate.
- 6Install Your Sump Pump
Prepare your discharge pipe by cutting a portion of 1 ½ inch PVC pipe so that it can reach through your sump basin lid and connect it into your discharge system. Use a threaded female outlet with a male adapter on the PVC to secure it in place on the pump. Once you have the start of the PVC drainage pipe measured and connected, you can place the sump pump into the sump basin. Pass the pipe through the lid and connect to a check valve. This will allow the sump pump to drain water out of the basin, and the check valve will prevent drainage from pouring back into the pump.
- 7Connect The Power
Pass the power cable through the lid of the sump pump. This should be connected into an outlet but not switched on yet until everything is ready. You may need to do some electrical work to make sure the power cable can reach an appropriate outlet.
- 8Install A Vent
Sump pumps need proper ventilation, and it's usually required by local and state codes. However, it's simple to vent your basin. You need a PVC pipe to run from the base of the basin to the exterior of your home. Measure a length of 1 ½ inch PVC pipe so that it can reach from the bottom of the basin to just over the basin lid.
- 9Run The Pipes
Once you have your discharge and venting PVC pipes coming out of the basin, you need to run them. Use connections and pipes to connect your drain line to your home's plumbing and run your ventilation pipe outside your home. This is the most time-consuming part but isn’t too challenging to complete. You may need to cut holes in your wall to allow these pipes to pass. If this is the case, you should make sure to cover the gaps with rodent guards to stop rats or mice from making their way in.
- 10Seal The Pump
Once everything has been connected, you should seal the basin lid by tightening the bolts around the outside. Fill the gaps around the basin with the drain aggregate.
- 11Finish The Wiring
Run the wires of your sump pump into your home to the nearest power source. You’ll typically need 20 amps for most sump pumps, and you’ll need to make sure it’s connected to your circuit breaker. You may want to get a professional to help you with the electrics if you’re not sure.
- 12Test The Pump
Turn the power on at the circuit and test the pump. They are usually triggered with a floating arm that detects water in the basin, so you’ll need to pour some water into the basin until it starts working.
Average Cost To Install Sump Pump In Crawl Space
There are two main types of sump pumps: submersible and pedestal. Submersible sump pumps are more expensive but more effective at removing moisture. We'd recommend a submersible sump pump in your crawl space if you can afford it. Here’s a quick breakdown of each type and the associated costs:
Submersible pumps are designed to be kept in the basin's water and are surrounded by a waterproof casing. When the water level rises, these pumps pull in water through the pump and direct it out through the discharge pipes and into your plumbing.
This type of sump pump is more effective than pedestals and better suited for very wet areas. They are less prone to clogging, so there's less maintenance needed, but they won't last as long as pedestal pumps.
This style of sump pump is more expensive as they must be more protected from the water. The installation is also more complicated because they are in the basin itself. You should expect to pay $150-$350 for a submersible sump pump itself. For parts and labor, it will cost you roughly $1100-2500, depending on your exact circumstances.
Pedestal sump pumps sit outside of the sump basin. They use a pump and hose system to draw water from the basin and into your drainage pipes. Having the pump sit separately makes it easier to access and makes installation and maintenance less hassle.
The disadvantage is that they take up more room in your crawl space which not everyone can accommodate, and they don’t work as effectively. This means they’ll drain water more slowly and can’t deal with very wet conditions or flooding.
Your pedestal pump is cheaper to buy and more affordable to have installed than a submersible. You'll typically pay $100-$200 for the pump and another $100-$400 in labor. This means, in total, it will cost you roughly $200-$600 for parts and labor.
People Also Ask (FAQs)
What size sump pump do I need for my crawl space?
The size and power of your sump pump is measured in horsepower (HP). Most average households will need a 1/3HP sump pump for their crawl space, but if you live in a wet area, you might need a larger one to remove water faster.
Is there an alternative to a sump pump?
There are some effective alternatives to sump pumps. Waterproofing can help stop water from getting into your home, but it can be challenging to maintain. French drains with sloped pipes can work well but won’t catch all of the water. Larger jobs like landscaping and grading can also help, but they involve a lot of groundwork to slope the earth around your home.
All of these are viable alternatives to sump pumps but can end up being more work for worse results.
How long does crawl space sump pump installation take?
It will typically take 1-2 days to complete the work, but it can be done quicker if you have help.
How long does a crawl space sump pump last?
Submersible crawl space sump pumps will last 5-15 years, and pedestal crawl space sump pumps will last 10-30 years. Make sure you’re maintaining the pump properly, so it lasts as long as possible.
Protecting your crawl space will help to protect your whole home. A crawl space sump pump will help remove the water safely and save you a fortune in repair work. Hopefully this guide has given you some useful information, and you now feel confident that you can install your crawl space sump pump yourself.
Ian Haynes is an expert writer who has successfully deployed over 500 plumbing pages and other related content. He has an excellent understanding of home plumbing issues and translates his experiences via Plumbing Lab so readers can have a better understanding of common household problems. Outside of his work, Ian likes exploring Brooklyn with his Labrador.