1000 Gallon Septic Tanks | Complete Buyers Guide

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Guide To 1000 Gallon Septic Tanks

If we’re going to crown a single hero inside your home, the septic tank is an underappreciated one. Your septic tank is the hero you need, working round the clock to keep your waste products out. Among many septic tank systems, the 1000 gallon (3684.5 L) unit is among the best.

How big of a home can a 1000 gallon Septic Tank accommodate? 1000 gallon septic tanks are a great pick for any small home. They can handle the waste of a 1 to 2-bedroom home and fits the needs of a small to medium family. The average cost of a 1000 Ga septic tank installation should go around $2200 to $5200. This range depends on the type of septic tank, water consumption, and what homeowners do at home.

If you’re not sure if a septic tank system is right for you, let’s explore the details of the product. Let’s check what kind of septic tank unit you need. Here’s why we think the 1000-gallon (3684.5 L) septic unit is for you.

Before You Buy A Septic Tank

During the olden days, much of septic tanks were simple concrete boxes. These would then go into the backyard, buried there, and handle the movement of your waste products. Sure it wasn’t a very cheap installation, but it was an essential part of your home. You can’t go without it at all.

Most older homes will have these kinds of systems, but most states will have newer regulations. These regulations will likely clash with the ones installed at an old home. You must understand the regulations in your own state.

If you are buying a home with a septic system, the best way to deal with it is to have an inspection. By law, most states would need certified septic tank contractors or plumbers to assess the septic tank. They need to follow through the right procedures and furnish you with the information you need. The septic system needs to follow at least the minimum standards for local homes.

If you are about to install a septic tank system or have one already, you need the tanks inspected. All the system tanks would need to have pumps undergo visual inspection for capacity and tightness. For more information on septic tank installation and cost, read this.

Your certified evaluator needs to look for potential damages, cracks, leaks, and defects. They would also need to look for:

·         required outlet devices

·         filters

·         access ports

·         condition and fit of the lid

Certifications and evaluations are valid for 5 years so that new units can use such documentation. If you’re moving to a home with a septic tank, documentation less than 5 years old is good enough.

Before installation, you would also want to have your potential drainfield area inspected. Evaluators would need to determine:

·         location

·         type of drainfield material

·         configuration

·         size

Inspectors will inform you if there is any failure on this level of preparation from your side. Drainfield elevation above the seasonal high water table will also be for evaluation. If your potential septic tank has accessories, those will undergo inspection too.

What Are The Dimension of A 1000 Gallon Septic Tank?

Among the most common septic tank dimensions is the 1000 gallon (3684.5 L) septic tank. It’s easy to source and install, but do you need it? Can your home accommodate it?

The size of the 1000 gallon septic tank can vary depending on the manufacturer. Septic tanks will have a variety of sizes, shapes, and styles. Each one will have a different dimension, depending on the shape.

For concrete rectangular septic tanks, the common size depends if it is heavy-duty or low-profile. Heavy-duty septic tanks have a size of 96 inches long, 78 inches wide and 61 inches deep (96 x 78 x 61 inches, 243 x 198 x 154 cm). The low-profile 1000 gallon septic tank has a dimension of 120 x 67 x 57 inches (304 x 170 x 144.8 cm).

To get exact dimensions, it’s best to talk to a manufacturer to provide you with their size charts. For example, other septic tank shapes include spherical, cylindrical, or two-compartment.

You would also need to calculate the materials. Plastic or fiberglass septic tanks, for example, follow a different and more low profile dimension. Steel septic tanks follow an even sleeker set of dimensions.

If you want to know what dimensions you need, the easiest way to do it is to calculate for size. Every shape of the septic tank needs a different calculation. You would want to calculate for the volume before you even get the tank installed.

For rectangular septic tanks, multiply the length by the width and height in feet. Once you get the cubic capacity in cubic feet, multiply this by 7.5 to get it in gallons. For rounded septic tanks, multiply the radius squared by 3.14, then multiply it by depth. Multiply the resulting cubic feet by 7.5 to get it in gallons.

You also need to ask your manufacturer the internal size of the septic tank. Remember that for fitting your septic tanks, the external dimensions are crucial. If you want to know the actual capacity of the septic tank, however, you need the internal dimensions.

What Size Home Can A 1000 Gallon Septic Tanks Accommodate?

Now that you know the different types, what size of home do I need to accommodate a 1000 gallon septic tank? This detail can vary depending on a few factors.

As a rule of thumb, a 1000 gallon (3684.5 L) unit should be able to handle a home below 2500 square feet (232.25 sq. m). Another way to calculate this is you need the 1000 gallon septic tank for homes with 0 to 3 bedrooms.

Why bedrooms matter?

The number of bedrooms assumes that these all have people sleeping in them. With 3 bedrooms maximum, you’re looking at a range of 3 to 6 people as residents of the home. Of course, the calculation goes off if you live in solitude in a three-bedroom home.

Is there a better way to do the calculations? There is, and the basis for it is the total water usage in your home. If your consumption is equal or less than 550 gallons (2090 L) of water per day, a 1000 gallon septic tank is right for you. For a family of 3 to 6 people, this should be more than enough.

The water consumption calculation considers all the use that you get from your water. This usage includes laundry, car washing, bathing, and toilet use.

Read this for more information on how big of a septic tank you may need.

What’s The Cost of A 1000 Gallon Septic Tank Installation?

What’s the cost of a 1000 gallon septic tank installation? This installation will depend on many variables, especially the quality of the septic tank. The range price of a 1000 gallon septic tank will go between $2200 – $5200.

Why the large range discrepancy? Depending on the materials of your septic tank, you can either save upfront or invest now.

Pre-cast concrete septic tanks cost the lowest to form, at around $600 – $1000. Polyethylene or plastic septic tanks are very low cost, up to around $1400 for a 1000 gallon unit. Fiberglass septic tanks will cost around $2300, which are more durable than plastic. Steel septic tanks are old and obsolete.

The more common types of septic tanks are anaerobic and aerobic. There are further ways to breakdown their categories, but the costs should be almost the same. Aerobic systems are more expensive to install than anaerobic systems due to their special setup.

Why? For starters, most a basic drainfield with a standard 36-inch (91.44 cm) wide gravel trench would need 12 inches (30.48 cm) of material. You would also need to install it at around 12 to 36 inches (30.48 – 91.44 cm) deep. On materials alone, you’re looking at the cost of $15 – $30 per ton of gravel.

PVC piping with 4-inch (10.16 cm) of perforations will cost around $80 for 100 feet (30.48 m). Risers will cost another $100 – $200, depending on the material. Permits, installation, and labor will cost you more, between $1500 – $4000.

This cost doesn’t count the maintenance costs that need to happen. Standard septic tanks would need some maintenance every 3 to 5 years. Aerobic septic tanks would need mot maintenance, with ATUs costing the most across all systems.

Concrete Vs Plastic Septic Tanks: Which One Is Better?

Concrete vs. plastic septic tanks has been a question since the early days of their invention. Different materials have different advantages, with steel and fiberglass as the other options.

Which one works better for you?

Concrete septic tanks are very durable for decades if you install them properly. Even then, you can start experiencing cracks on concrete septic tanks if there’s sub-standard material used. These tanks can experience a crack or separation. If your septic tank cracks, leaks of the effluence can happen and even let groundwater to seep.

If you’re experiencing a blockage, it can also be a problem. Concrete can’t handle too much runoff, and the eye test should show the problem when it happens.

Plastic, on the contrary, is very cheap and very resistant to rust, allowing a longer lifespan for the installation. The problem with plastic is its questionable durability. Plastics are also prone to punctures, which can push your septic tank to fail.

The primary issue with plastic septic tanks is their potential for breaking down. If you are having a plastic septic tank installed, ask them for extra care. While plastic has the resistance for many types of other materials, punctures are not what you want with it. Careful installation can save you a ton of money.

Steel systems are among the oldest materials for a septic tank. Steel is the least desirable of all the materials. While it’s durable and lasts for a while, they’re still in use in older homes.  Steel septic tanks can last between 20 – 25 years. Most of the top covers also need proper handling as they open risks for people falling into the septic tanks.

The last material is fiberglass, which is the most expensive of the bunch. Its pricing and issues are almost the same as plastic. The primary difference, however, is the more durable construction. The only downside is you’re paying too much to be in there.

Most fiberglass septic tanks are durable but can be a pain to work with. You still need to pay attention to the way your contractor is installing it. You would also need to avoid putting anything heavy on top of the septic tank as these won’t be durable enough.


When it comes to 1000 gallon septic tanks, it’s best to have the right knowledge when buying one. Consider the issues you are experiencing at home to know what kind of septic tank you need. 1000 gallon tanks are best for a small family with 0 to 3 bedrooms and below 2500 square feet (232.258 sq m).

When picking septic tanks, it’s best to consider the materials. Invest in superior materials and make sure that the design is right for your home design. You would also want to consider environmental factors that can help keep your effluent in check.

Are you looking for a septic tank? We’re sure you’d find this guide helpful. Follow the information that we gave and talk to a professional too. It will help you determine if you’re on the right track.