Skip to Content

Can 2 Houses Share a Septic Tank? (Is It a Good Idea?)

Can 2 Houses Share a Septic Tank? (Is It a Good Idea?)

A septic tank is an invaluable asset to any property owner. That’s where all the wastewater from your home, whether from the kitchen, bathroom, sinks, or laundry, goes. It is a self-contained unit that uses bacteria to break down the waste before safely releasing it into the environment. So, in other words, a septic tank is an indispensable part of any modern home – and many homeowners already know that.

Nevertheless, one thing about tank systems that most people don’t know is whether or not it’s safe for two houses to share a septic tank. After all, we know that septic tanks can be very delicate, and sharing one might put too much strain on them. So, can 2 houses share a septic tank?

Well, perhaps that’s the same question that you have in mind. And fortunately, we have the answer for you in this article. Just follow us to the end to discover everything you need to know about this topic!

Can Two Houses Share a Septic System?

Yes, two houses can share a septic system, but there’s more to that answer. Sharing a septic system, for instance, is only possible if the current tank can still accommodate another household. If not, then it’s a definite no. Also, for sharing to be possible, there’s a need to go through a legal procedure and process to ensure that both parties are comfortable with sharing.

Perhaps your neighbor has approached you with the idea of sharing your septic tank. Or, it could be you are planning to buy a house, and in the course of checking things out, you discovered that the property you are interested in shares a septic tank with another.

In both cases, it makes sense to know more about the idea of sharing a septic system before you make any decisions. After all, we know the greater the number of people using a septic system, the greater the chance of problems developing.

And about whether or not two houses can share a septic system, the answer is – yes! But as we have already stated, certain conditions must be met for this to be possible. Let’s take a close look at each of them.

The Capacity of the Septic Tank

The number of bedrooms in a house is one way to determine the size of the septic tank needed. For instance, a one-bedroom place will require a 1,000-gallon tank. The more the number of bedrooms, the more likely the number of users to be high, and the greater the capacity of the septic tank needed.

So, if your tank has enough capacity for four bedrooms but serves a two-bedroom house, you can share the tank with another household. But if your tank is only for three bedrooms, then it’s probably not a good idea to link a 2-bedroom house, assuming you have a 2-bedroom as well.

Legal Procedure

Sharing a septic tank isn’t just an agreement you strike with your neighbor. No, it needs approval by the local health department. Well, the body responsible differs depending on the area you reside. But in most cases, it’s the county’s building or health department.

Either way, you need a permit before you can start sharing a septic system with another household. Sometimes the approving body can send the county’s geologists to inspect the site and make sure that it is feasible for two houses to share a septic tank. Then, the owner of the septic is supposed to grant the other party a septic easement, the legal right that gives the requesting party permission to use the septic tank.

Are Shared Septic Systems a Good Idea?

Shared septic systems are a good idea as long as the septic tank is large enough to accommodate the needs of the two households. Also, the other party should be just as meticulous about taking care of the septic tank as you are. Otherwise, sharing a septic tank with your neighbor could be one of the worst decisions.

Septic tank sharing can be good or bad. It all depends on the size of the tank and the other person. As for the tank size, it must be able to accommodate the needs of both households. If not, then it’s best to steer clear of the idea. Sometimes the sharing intentions may not succeed, especially if the local health or building department has to send geologists to inspect it.

As for the person, they must be as committed to taking care of it as you are. That’s because once you agree to share your septic with another person and grant them a septic easement, you aren’t only committing yourself to share the costs of maintenance with them but also to suffer their liability should they damage the septic system.

So, whether a shared septic system is a good idea comes down to the pros versus cons. Weigh everything out and see what works best for you.

Some of the pros of sharing a septic system include;

  • Saves money – When you share installation and maintenance costs with another person, it lightens the financial burden.
  • Convenience – If you live near the person you are sharing the septic tank with, it’s more convenient.
  • Shared responsibility – As we mentioned earlier, using a septic tank with another person also means sharing the responsibility of taking care of it. So, if something goes wrong, you can rest assured that the other person will also be there to help you fix it.
  • Strengthening the bond – In some cases, sharing a septic system with another person may actually help strengthen the bond between you and the other person. That’s because it acts as something to bring the two of you together.

Potential Problems With Shared Septic Tank

Some potential problems with a shared septic tank include; improper usage of the septic by the other person, decreased property value, conflicts with neighbors, and several others. Ensure you assess the two sides of the coin before making a decision. Otherwise, you may end up regretting making the wrong decision.

While sharing a septic tank can be beneficial, sometimes the cons can be more pronounced than the benefits.

Let’s take a closer look at each of these potential problems;

1. Improper Usage of the Septic by the Other Person

One of the potential problems with a shared septic tank is that the other person may not use it properly as they’d if it were their own. And if this happens, it could lead to septic backup, clogging, and other problems. You may also need to suffer more on repair costs.

2. Decreased Property Value

Since septic is an essential part of your property, it accounts for a certain percentage of your property’s value. When you share it with another person, the value of your property automatically decreases.

3. Conflicts With Neighbors

Sharing a septic tank with another person can sometimes lead to conflicts, especially if one person isn’t happy with how the other uses it. Septic tanks are usually located in the ground and need emptying every few years to remove the accumulated solid waste. If one person neglects to do this, it could lead to disagreement.

4. Getting an Installation Company Can Be Challenging

Installation companies suffer the consequences in case of a problem with the septic tank installation. Of course, no company wants to deal with such a problem. And so, most of them tend to avoid it.

How Close To a House Can a Septic Tank Be?

A septic tank should be at least 5 feet away from the house. However, in most cases, a septic tank is located 10 feet from a house, while the leach field is as far as 20 feet away. Placing a septic tank closer to a home can increase the risk of septic problems, damage the foundation, or even cause water contamination.

Where a septic tank serves two houses, the location of the tank is usually at the border. That’s especially true if the sharing plan existed even before the construction of the houses. In some cases, the septic tank may be on land owned by a third party.

Should You Buy a House With a Shared Septic Tank System?

Yes, you can buy a house with a shared septic tank system if you like everything about it and are willing to direct your disposable income to repairs should they be necessary. But if you aren’t ready to deal with expensive repairs, conflicts with neighbors, and the like, it’s best to find another house. And as usual, if the idea of sharing the septic tank settles well with you, have a professional come and inspect it to guarantee that it is in good working condition.

When buying a house, you should also consider the location of the septic tank. If the two are too close, there’s a higher risk of septic problems. You should also check the leach field to see if everything is in good condition.

Is Dawn Dish Soap Safe For Septic Tanks?

Yes, Dawn dish soap is safe for septic tanks. Dawn dish soap doesn’t contain phosphates or other harmful chemicals to septic tanks. So, unlike some soaps that have them, Dawn dish soap won’t kill the microbes in your septic tank that are responsible for breaking down the solid waste.

Septic tanks use anaerobic digestion to break down solid waste. This process doesn’t require oxygen, but it does require bacteria. The bacteria in your septic tank create an environment that is conducive to the anaerobic digestion process.

And like any other living thing, these bacteria need food to survive. The primary food source for the bacteria in your septic tank is the solid waste that goes into it. So, using dish soap containing harmful chemicals is actually killing the same bacteria that keep your septic tank functioning properly.

But as for Dawn dish soap, you can use it without worrying about harming the bacteria in your septic tank.

Does Bleach Harm Septic Systems?

Yes, bleach can harm septic systems. Bleach is a powerful chemical that can kill the bacteria in your septic tank, eventually leading to septic tank failure. That’s why you should avoid using bleach or any products containing traces of bleach if you have a septic tank. Otherwise, you could stir up a lot of trouble for yourself and your neighborhood.

So, generally, avoid having bleach go down to the septic. Other products to keep off your septic system include paint, disinfectants, pesticides, solvents, medicines, and others. This article will give you a longer list of the things that shouldn’t touch your septic system, some you don’t even expect!

Final Verdict

Sharing a septic tank with your neighbor is doable but not always the best idea. It can lead to expensive repairs, conflicts with your neighbor, and other problems. So, if you’re thinking of sharing your septic tank or buying a house with a shared septic tank system, consider the pros and cons first. If possible, have a professional septic inspector check the system to ensure it’s in good working condition.