Septic Tank Size Chart: Common Dimensions & Capacities
As a homeowner, it’s important to know the different septic tank sizes and what each one is capable of. This article will provide a comprehensive guide to septic tanks, including their dimensions, capacities and industries where they are commonly used. This article will discuss underground septic tanks in terms of size or the total volume handling capacity.
Regulations to be Aware Of
Before you install a septic tank, check with your state's environmental department and local city or county building office for approval. Different states have different requirements for the size and placement of the tank, as well as what materials can be used in its construction. Your soil type will also affect how large the drain field needs to be, so be sure to have that professionally assessed before finalizing any installation plans.
Another thing to consider is if the septic tank is for residential or commercial use because there are usually different regulations for each type. Lastly, the specific septic tank system already installed or will be installed can also change the required tank size.
What Type of Septic System Will You Install?
There are up to nine types of septic systems. The septic systems are listed below and can use polyethylene septic tanks if they require a tank.
- Conventional System
- Chamber System
- Drip Distribution System
- Aerobic Treatment System
- Mound Systems
- Recirculating Sand Filter System
- Evapotranspiration System
- Wetland Septic System
- Cluster Septic System
Some of these are known by other names, but the most common systems in use today are the conventional and chamber systems. The primary difference lies in how the drain fields are constructed. The conventional system uses gravel-filled trenches for drainage. The chamber system is gravel-less and uses some type of fabric-wrapped piping to distribute the liquid.
How are Septic Tanks Constructed?
Before you decide on a septic tank size, familiarize yourself with the different types of septic tanks. The most common type is concrete, but they require heavy-duty and expensive equipment for installation because they are so hefty. Fiberglass and plastic septic tanks are lighter in weight and can be placed in hard-to-reach or remote areas.
Variables That Affect the Size of the Septic Tank
A septic tank too small for a home will cause many problems, such as bad smells, flooding and blockages. The most common result of a septic tank that is too small is the water being released before it is purified. This means the solid waste in the septic tank won’t be broken down and will collect faster, which can cause overflows and blockages.
Is it possible to have a septic tank that's too big? If you're disregarding cost, then the answer is no. A correctly installed septic tank can never be too large — it can only be too small. In fact, most experts recommend going with a bigger size because it's often a safer and more preferred option. While a larger septic tank is more expensive, it will save you money in the long run as your family or home size increases.
- Water Usage: To find the most appropriate septic tank size for your home, you'll need to think about how much water you use daily. A septic tank's capacity determines how much waste it can hold before it needs to be pumped, which will impact the performance of your soil absorption field.
- Size of Your Home: While the size of your home is often considered a factor in selecting the proper size of a septic tank, the main issue is the number of bedrooms. That determines how many people will use the home, and average water usage is based on individuals living in the home.
- Existing System: If there is an existing septic system on your property that will not be replaced with the new system, this will affect how big the new tank can be. Each system will require a specific amount of space for a drain field, and the projected water usage for the new system may limit the size of the tank.
Recommended Septic Tank Sizes
Septic tanks come in different configurations, depending on the needs dictated by property size and geology. There are single-compartment tanks, double-compartment tanks, low-profile tanks and holding tanks for jobsite and RV use. Here are some recommended septic sizes, depending on the number of bedrooms. Your specific situation may alter these.
- A one- to two-bedroom house requires a 1,000 - 1,500 gallon tank.
- A three-bedroom house requires a 1,000 - 2,000 gallon tank.
- A four-bedroom house requires a 1,250 - 2,500 gallon tank.
- A five- to six-bedroom house requires a 1,500 - 3,500 gallon tank.
Dimensions of Various Septic Tanks
These figures are based on single-compartment tanks:
- 750 gallon: 92 inches x 60 inches x 51 inches high.
- 1,000 gallon: 127 inches x 60 inches x 51 inches high.
- 1,250 gallon: 157 inches x 60 inches x 51 inches high.
- 1,500 gallon: 157 inches x 69 inches x 51 inches high.
Additional Uses for Septic Tanks
While most people are not going to re-purpose a tank that has been collecting sewage, a new tank can be used for purposes other than storing wastewater, such as rainwater harvesting or stormwater collection.
Tank Depot Specializes in Septic Tanks for Residential and Commercial Needs
Here at Tank Depot, we have septic tanks in various sizes to fit any need, including pre-plumbed septic tanks, pump tanks, and other septic system components. Our septic tanks are made of durable, long-lasting materials, such as fiberglass and polyethylene, so they are perfect for residential, commercial and industrial applications.
Whether you need a septic tank for a small home or large business, Tank Depot has the septic tank that is right for you. Talk to an expert to find out more information.