When it comes to wastewater management, types of septic tanks play a crucial role. Whether you’re considering a small septic tank for a compact property or looking into options like plastic septic tanks, concrete septic tank lids, or prefabricated designs, choosing the right one can save you time, money, and future headaches. This guide explores the three common types of septic tanks available, highlighting their unique features, as well as the pros and cons of each, to help you make an informed and confident decision.
Let’s break it down!
Do you need a new septic system? I get it, this may be the most exciting project for your home, but it’s a lie! But believe me, it’s a critical decision because it can save you a lot of money and headaches in the future. Therefore, this project should not be taken lightly.
First, you must consider the types of septic tanks to choose from, among which we have: concrete septic tanks, plastic septic tanks, and prefabricated septic tanks (Fiberglass or Steel).
Which of these types of septic tanks is the best? The answer is that it depends, each one has its pros and cons, and the best choice will always depend on the specific needs, the budget, and the conditions of the place where the installation will be made. Rest assured, today we will thoroughly explore these details together. By the end, you’ll be equipped with all the essential information to confidently select the septic tank options that are perfect for your needs!
Table of Contents
1. Concrete Septic Tanks: The Heavyweight Classic
Concrete septic tanks are a classic. Concrete septic tanks have always existed, and we can assure you that they are one of the most durable options, which is why they continue to be one of the most popular choices. These types of septic systems are like having a strong and sturdy brick house that will last for decades. In resistance and durability, there is nothing that compares to it. But it is important to explore the pros and cons to better understand:
Pros of Concrete Septic Tanks:
- Durable and Long-Lasting: With proper maintenance these types of septic tanks can have a useful life between 30 to 50 years. If you don’t know what I mean by maintenance, I recommend that you read the article: “Septic Tank: Your Essential Guide to Understanding, Maintenance, and Benefits” where you will find information that can clarify this matter for you. So, if your priority is for your septic system to last longer than it will take you to pay your mortgage, concrete is a solid choice!
- Handles Heavy Loads: If due to the use or design you have on your land, you require the top plate of the septic tank to support heavy loads such as heavy vehicles, and structures, or you are going to have a lot of activity or traffic in this area, a concrete septic tank is an excellent option.
- Corrosion Resistant: Concrete is a material that withstands the acidic environment characteristic of a Septic Tank quite well and unlike other materials such as metal, it does not rust.
Cons of Concrete Tanks:
- Heavy and Hard to Install: Due to the characteristics of the material, heavy machinery and equipment are required for installation, which makes the construction process more complicated and expensive. In the end, we are talking about this type of septic tank being a system that weighs several tons.
- Potential for Cracking: This is one of the biggest cons that this type of septic tank can present, due to the intrinsic characteristics of the material. The biggest problem with cracks is leaks and infiltration of untreated wastewater and potential contamination of your land and water sources. Cracks can occur due to incorrect installation or movement of the ground.
When to Choose Concrete Septic Tanks?
If what you are looking for is durability, and the time and complexity of installation are not a problem, Concrete Septic Tanks are an excellent choice. Please note that these types of septic tanks require very stable soils.
Concrete septic tanks have been a trusted choice for decades. These heavyweight systems are known for their strength and durability, making them ideal for long-term installations.
2. Plastic Septic Tanks: The Lightweight Contender
Due to their easy and quick installation, plastic septic tanks have become very popular in recent years. These types of septic tanks are made of polyethylene or polypropylene, which makes them lightweight and flexible. If we do a comparative example, a plastic septic tank would be like lifting a plastic garden chair, while a Concrete Septic Tank would be like lifting a solid concrete bench, nothing that your chiropractor recommends.
Pros of Plastic Septic Tanks:
- Easy to Install: Due to its weight characteristics, heavy machinery is not required for installation or transportation.
- Resistant to Corrosion: It does not corrode because it is made of plastic, therefore neither rust nor chemical decomposition will have a problem.
- Watertight Design: The design of the plastic septic tank is a single piece, which helps prevent leaks that can be generated by poor coupling of sections.
Cons of Plastic Septic Tanks
- Shorter Lifespan: its useful life can be less than half that of a concrete septic tank if adequate maintenance is carried out.
- Vulnerability to Shifting: Where water tables are high and soils are unstable, these types of septic tanks can shift or even float, especially if they have not been properly anchored.
When to Choose Plastic Septic Tank:
This type of septic tank is a good option when soil conditions are suitable, as we have already discussed. Also, when a Septic System is required in a remote location where there is no accessibility to heavy machinery.
3. Prefabricated Septic Tanks: The Customizable Option
This type of septic tank is made of fiberglass or coated steel. They are manufactured in custom-controlled environments and delivered ready to use, this makes installation quick. If you want a modern and versatile option, Prefabricated Septic Tanks are the alternative.
Pros of Prefabricated Septic Tanks:
- Quick Installation: Installation is quick because there are systems that arrive pre-assembled.
- Custom Sizing: You install what you need without having to limit yourself to standard dimensions that sometimes are not what is needed.
- Corrosion Resistant: Fiberglass and steel coated with materials resistant to the corrosion that is generated in the acidic environment characteristic of a Septic Tank.
Cons of Prefabricated Tanks:
- Higher Upfront Cost: Due to the specialized materials required in their manufacturing and the customization in the manufacturing processes, these types of septic tanks are more expensive.
- Special Equipment Needed: Depending on the size of the tank ordered, larger Prefabricated Septic Tanks require specialized equipment for transportation and installation, this factor further increases the cost.
When to Choose Prefab:
If the soil conditions match those of an area with high water tables, and unstable soil and you are willing to invest a large budget that allows you to customize your system, your option to choose is a Prefabricated Septic Tank.
Concrete vs. Plastic vs. Prefabricated: A Quick Comparison
| Feature | Concrete | Plastic | Prefabricated |
|---|---|---|---|
| Durability | 30-50 years | 20-30 years | 20-40 years |
| Ease of Installation | Difficult (heavy equipment needed) | Easy (lightweight, minimal equipment) | Moderate (specialized equipment needed) |
| Cost | Moderate | Low to Moderate | High |
| Best For | Long-term use, heavy loads | Quick installations, remote sites | Custom needs, tough site conditions |
Climate Considerations: What’s Best for Your Area?
Climate and weather conditions can have an impact on the efficiency, performance, and durability of septic tanks. Therefore, it is an issue that is worth understanding and considering when deciding. At this point, we will examine promptly, but practice how the different materials of septic tanks behave in different weather scenarios, let’s start with:
- Cold Climates: Because Plastic Septic Tanks and Prefabricated Septic Tanks are less likely to crack, they tend to perform better in subfreezing temperatures.
- Hot Climates: Concrete is a material that tends to better resist intense heat; however, special care must be taken to avoid cracking the upper covers that are exposed.
- High Water Tables: In this scenario, Prefabricated Septic Tanks are the best alternative since the chances of them floating are lower compared to a Plastic Septic Tank.
Final Tips for Choosing the Right Septic Tank:
1. Consult a Professional: Making the final decision regarding which is the best types of Septic System for your case is not something that should be taken lightly, getting advice from an expert who evaluates your soil type, water table, and climatic conditions is always an excellent option. But remember that in the end the decision will always be yours and having sufficient information to allow you to make a judgment call will be your greatest peace of mind.
2. Consider Long-Term Costs: Always remember to compare apples with apples, although Plastic Septic Tanks may initially be cheaper, their useful life is shorter, which means replacement costs must be incurred. While Concrete Septic Tanks may initially have a high investment, when we consider their useful life span, they generally have better value over time.
Septic Tank Sizing Considerations by Material
It is important to keep in mind that the different size and capacity options available for the different types of septic tanks are directly related to the material from which it is made. Let’s look at it for each of the systems:
Concrete Septic Tank These types of septic tanks are usually available between 500 to 2,000 gallons in capacity. Considering that the type of manufacturing is personalized, they allow specific requirements to be met, although this may imply a higher cost. Don’t forget that the weight and volume of the Concrete Septic Tank may limit its installation in areas that are difficult to access or when you have space limitations.
Plastic Septic Tank are generally manufactured in ranges from 500 to 1,500 gallons of capacity. As we have already mentioned, they do not allow you to customize specific requirements. Larger capacity Plastic Septic Tanks are sometimes impractical due to transportation challenges.
Prefabricated Septic Tank, although its capacity can be customized to the needs of each client, they are manufactured in sizes from 500 to 3,000 gallons. Their manufacturing process allows them to be adjusted to precise requirements. Larger capacity tanks can create installation challenges in some environments due to their weight and volume.
Choosing the Correct Septic Tank Size
The adequate capacity of a septic system is directly associated with the number of rooms the house has and the calculation of the daily flow of wastewater. This calculation is not so obvious since it is not obvious to determine how long it takes us to take a shower or how many times a toilet is flushed per person per day. However, there are general guidelines that help us have a close calculation of the Septic System capacity we need.
Before arriving at general guidelines, always take local regulations into account as the general guideline may require deviations to fit specific site conditions.
As a general guideline:
| Number of Rooms | Septic System Capacity (gallons) |
|---|---|
| 1 to 3 | 1,000 to 1,500 |
| 4 to 5 | 1,500 to 2,000 |
| 6 or more | 2,000 or more |
Frequently Asked Questions
What are the main types of septic tanks?
Concrete, plastic, and prefabricated tanks are the most common types.
Which type lasts the longest?
Concrete tanks, with proper maintenance, can last 30–50 years.
Are plastic tanks prone to leaks?
Not typically. Their one-piece design minimizes leakage risks.
Do prefabricated tanks require special installation?
Yes, larger prefabricated tanks often need specialized equipment.
What factors affect septic tank size?
Household size, daily water usage, and local regulations determine the appropriate size.
How do concrete tanks handle extreme weather?
They resist heat well but may crack in freezing conditions without proper care.
Can I install a plastic tank in high water table areas?
It’s possible but requires secure anchoring to prevent floating.
Are prefabricated tanks worth the cost?
For customized needs or challenging conditions, they’re a great investment.
What’s the biggest drawback of concrete tanks?
Their weight makes installation costly and time-consuming.
Which type of septic tank is best for remote locations?
Plastic tanks are ideal due to their lightweight and easy transport.
The Bottom Line: Find What Works for You
As we can see, each situation is particular and requires an evaluation. If you opt for something strong and durable and the soil conditions allow it, choose a Concrete Septic Tank. If, on the other hand, an installation that does not involve heavy and fast machinery is needed, the alternative is a Plastic Septic Tank. If a custom system is a priority, consider a Prefabricated Septic Tank.
Whatever your final decision is, always remember that the Septic Tank is an investment in the future of your home, so always perform adequate maintenance and ensure that the installation is done well. It depends on a deep analysis that you will feel satisfied for many years.
Always remember that a careful and professional evaluation of your home’s needs, such as installation site conditions, will ensure proper septic tank sizing and material selection.
