How to Choose Between Plastic and Concrete Septic Tanks

When you are shopping for a septic tank, one of the most important decisions you’ll have to make is the type of tank you’ll purchase. Most modern septic tanks are made of either concrete or plastic. Both of these materials have their own unique advantages, so the right style will really just depend on your home and your preferences. Here are some things you need to think about while looking for a septic tank.


A large concern for many homeowners is the cost of a septic tank. If you want something affordable, plastic is often a good choice. Plastic tanks are quite a bit cheaper to buy than concrete tanks. On average, expect to spend at least a few hundred dollars more if you buy a concrete tank. Since they’re simpler to work on, you’ll also find that your repair bills will probably be a little lower if you pick a plastic tank. Once the tank is at the end of its lifespan, a concrete tank will continue to cost you more than a plastic tank. Concrete tanks can be quite costly to remove and dispose of when their usefulness is done.

Ease of Installation

If you want a simple septic tank installation, plastic might be a better choice. Because of their complex design and heavier weight, concrete tanks tend to require more professional input and take longer to install. The concrete tank installation process can be a little disruptive, so plastic tanks can be more convenient for homeowners to put in. Also, consider the challenges associated with transporting the tank to your property. Concrete tanks are very bulky and heavy, so moving them takes specialized equipment. If you live in a remote area with difficult roads, getting a plastic tank to your home can be significantly easier. It will also be easier to maneuver into place once it reaches your home.


Concrete is significantly more durable than plastic. A concrete septic tank can last up to 40 years while a plastic tank usually lasts around 30 years. Part of the reason for this longer lifespan is that plastic is more vulnerable to environmental changes. Things like soil vibrations or growing tree roots can cause a plastic tank to break while they barely affect a concrete tank. Consequently, plastic tanks often need more repairs than concrete tanks. Concrete tanks are also stronger, so if heavy equipment rolls over them, they are less likely to break. If your tank is going into an area that could get driven over, concrete is definitely the best choice. Another nice thing about concrete is that it’s not easy to puncture. If you’re doing work near the tank, it’s unlikely that you’ll be able to poke a hole in it.

Soil Type

Your soil will play a big role in your septic tank decision. It is a good idea to get your soil acidity levels tested before picking a tank. This is important because concrete is very vulnerable to acid. In high-acidity soil, cement will start to crumble away. Therefore, some people may need to get a plastic tank regardless of their other preferences. The unique construction of plastic septic tanks makes them work in acidic environments that other tanks cannot handle.

Likelihood of Issues

When it comes to maintenance and potential repairs, both styles have their own disadvantages. The main issue with plastic tanks is that they have the potential to “float.” When the water level is higher than usual, these lightweight tanks can shift, requiring you to repair a lot of your plumbing. Plastic tanks also require more maintenance to stay in good condition. Concrete tanks don’t float and are easier to care for, but they are more susceptible to rust and water-based corrosion. Concrete is also a little more likely to crack over time, especially if the concrete was mixed improperly. If your concrete tank breaks, fixing the issue could be tricky. These tanks can be quite complicated to repair.

Ultimately, if you want something durable and low in maintenance, concrete is a good choice. Meanwhile, plastic can work well if you want an affordable and easy-to-install tank. Still not sure which style is right for you? The experts at [company_name] are happy to help you go over the pros and cons of each design, and we’re comfortable installing both styles. In addition to septic tank installations, we also help people in Puyallup, WA and the whole Pacific Northwest with a variety of other plumbing tasks. We do everything from water heaters and water softening systems to drain repair and gas repiping. To learn more about our full range of services, give us a call today.

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