How To Build A Concrete Septic Tank


Spread the love

How can you build a concrete septic tank? In this article, we’re going to walk you through the process of how to building a concrete septic tank. We’ll begin by explaining what a septic tank is and why you would want to build one.

construction of a septic tank on site

Then, we’ll take you through the steps necessary for construction, including where to find the materials you need. Finally, we’ll give an overview of step-by-step instructions for how to build a concrete septic tank and finish it off with some helpful tips for construction in general. Let’s get started!

The main reason you would want to build a concrete septic tank is because of its advantages . These include:

Built to last: A concrete septic tank can last a lifetime, whereas a traditional one (like the one shown above) still has years before it must be replaced, if ever. You’ll also be able to keep your new septic tank close to where you live, rather than having to transport it far away.

Easy maintenance: Because a concrete septic tank is more durable than an existing one, you won’t have to worry about heavy equipment being required for maintenance. You can easily move your septic tank when necessary using just a shovel and a truck.

Better on the environment: Concrete septic tanks are better for the environment than traditional septic tanks. They decompose much faster and more thoroughly, leaving less room for harmful waste to enter the water system.

What is a septic tank?

A septic tank is a type of water treatment system. It’s an underground reservoir that holds wastewater. As the wastewater sits in the tank, it naturally decomposes there.

This natural decomposition process ensures that solid waste and other things that shouldn’t be released into the environment are filtered out. The water from the septic tank exits and flows into a drain field or leach field, where it filters out of the rest of the system.

Septic tanks are typically built in one of two ways: as concrete tanks or as traditional wooden ones. The traditional wooden ones are less durable than concrete ones and require maintenance every few years. Concrete septic tanks can last decades without requiring any maintenance at all.

They’re made by pouring a concrete wall around a steel septic tank. You’ll need to dig the hole deep enough and wide enough to accommodate the new concrete wall, as well as the steel septic tank.

On top of this, you’ll need to put a concrete floor for the septic tank underneath the surrounding soil. For the concrete wall, you can choose from a number of options. These include using a concrete form for your tank instead of pouring the concrete around the septic tank.

You can also choose to use a ready-made form, which will save you time and money but won’t be as sturdy or durable as one that’s made by hand. Finally, you can build your own form using rough-cut stone held together with cement mortar or polymer bond mortar.

Keep in mind that a concrete septic tank does not have to be built underneath an existing house. It’s up to you and your local zoning laws whether or not this is allowed. When building a separate septic tank for an existing home, you’ll need to follow the same basic steps for any other construction project. These include:

Excavation: Excavating the septic tank hole is the first step in this process. Use a survey level to mark the corners of the hole and use stakes with flags on them to mark the corners of the hole.

a concrete septic tank dug deep under the ground

Grid lines: This step will make digging your hole easier and more accurate. Using stakes and grid lines, draw out horizontal and vertical marks in your designated construction site. These will help you align all of your pipes exactly where they should go while digging.

Elevation: Once you’ve finished digging the hole, fill it up with water to check for sloping. Use this information to build the concrete wall around your tank, ensuring that it’s at a uniform height above the surrounding soil.

This is where you’ll need to get measurements and specifications from a contractor or local expert. You’ll want to ensure that there are no potholes or other destruction of your septic tank area during construction.

Longitudinal and transverse joints: The last step in this process will be assembling your concrete wall so that all of the pipes can pass through it. You’ll need to use plenty of mortar or polymer bond mortar to hold your concrete walls together.

After you’ve made sure that your longitudinal and transverse joints are perfectly aligned, you can check that the vertical joints are even as well. If everything checks out, you’re ready for filling.

Fill it up with crushed stone and gravel so that it’s level with the top of the surrounding soil. Adjust this layer so that it’s one inch below the top of the concrete tank itself. This will save you money in repairs down the road because your septic tank will have a longer lifespan before needing to be maintained or replaced entirely.

Moving forward, let’s talk about our next topic which is how to build a concrete septic tank.

Steps On How To Build A Concrete Septic Tank

Here, we will be discussing on the step-by-step processes on how to build a concrete septic tank. These steps are as follows:

  1. The first thing you should do is find an area in your yard that’s suitable for digging. Because you’ll be digging a hole there, it should be level ground that slopes downward from where the hole will be.

If possible, choose an area that slopes away from your house or any other structures you want to protect from ground water. Also, you should check on whether or not your area is prone to flooding.

  1. Take accurate measurements of the entire site that you want to dig in a grid pattern, making sure that all of your pipes will be in a straight line when they exit the ground level. Once you’ve checked the measurements, start digging a hole that’s at least 60 inches deeper than what you measured earlier.

You don’t have to make the hole exactly 60 inches deep; however, it’ll depend on what type of soil there is at your site and how much it’s likely to shift over time.

  1. Your concrete septic tank will be sitting on top of the ground. To ensure that it’s level, use a large flat stone to ensure that your soil is even and you don’t have any potholes or other damaging forms of soil. Then, mix enough concrete to fill up the space between the ground and your tank itself.
  2. Once all of the concrete has been poured into the hole, use a trowel for spreading out sidewalls at all three corners of this new basement area. This will prevent water from seeping into wherever your tank and septic system are located.

You can also use polymer bond mortar here to make sure that your wall is resistant to stress cracking or to make sure that cracks in the concrete won’t get worse over time.

  1. Now, you’ll have to pour enough sand into the concrete mixture so that it fills in the whole space between your tank and sidewalls. The goal here is to get the sand so that it fills your rectangular shaped hole equally.

You can place a stone at one end of this new basement and use a balance scale to make sure that your sand weighs evenly, or use a tape measurer to measure it out. You should also have enough water on hand during this step to make sure that the concrete is still being poured evenly.

  1. Once the whole space has been filled in with sand, you can begin to pour cement into the gaps between your septic tank and sidewalls. This will make sure that your drains are covered and that you don’t have any flooding during heavy rains, or if there are any old pipes inside where your concrete septic tank is located.

Adding cement to this area will also make it easier for you to keep the dirt around your new concrete septic tank dry when it rains.

  1. Fill it up with crushed stone and gravel inside as well as outside of your new septic tank area. Check on this layer’s dimensions so that it’s even with where you’ve already installed your concrete walls.

This step will help you keep your tank and septic system in perfect condition, ensuring that you don’t lose any water during the dry seasons and making sure that you don’t have to repair the tank anytime soon.

You should be extra careful when working with a concrete septic tank—especially if it’s a brand new tank. These are known to crack easily, and if this happens, then you’ll most likely have to order a new one.

If possible, use your own weight as well as equipment like wheelbarrows to wheel dirt around your construction area because they are too heavy for most people who are out of shape to push.


There are plenty of things to take into account when it comes to building your own concrete septic tank. You’ll want to make sure that you’re working with a contractor that can do this safely and with the use of the right materials.

The last thing you want is a crack in your septic system, so make sure that everything is taken care of before settling in.

We hope that our article has helped on your search for information about how to build a concrete septic tank. We also hope that you’re able to make an informed decision about choosing and purchasing one for your residence as well as your next home improvement and construction project.

construction of a concrete septic tank on site with a ladder inside

Spread the love

About the author

Pretium lorem primis senectus habitasse lectus donec ultricies tortor adipiscing fusce morbi volutpat pellentesque consectetur risus molestie curae malesuada. Dignissim lacus convallis massa mauris enim mattis magnis senectus montes mollis phasellus.

Leave a Comment