Septic tank installation costs: How much to expect to pay
Whether you're looking to replace your current septic tank or need to install one for a new home, you're looking at a hefty bill. Here's what you need to know.
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Septic tanks are essential to any home that isn't connected to a municipal sewer system, but they don't come cheap. Since they're buried in your yard, it's also easy to forget they require occasional maintenance to prevent expensive plumbing issues . That's why it pays to stay on top of the costs you can expect, whether you're installing a septic tank for the first time at a new home or replacing an old one.
Here's what you need to know about septic tank installation costs.
How much does a septic tank system cost?
A new septic tank in the process of being installed and buried
The cost of a septic tank system installation can vary greatly, but the general range is between $3,000 and $25,000, with the average landing around $8,000, according to local service review and recommendation site Angi . A new septic tank typically costs between $500 and $2,500, depending on the size you need. The rest of the overall cost is dedicated to the permits, surveys, soil work, and labor involved.
If you're just replacing an old septic tank, you may be able to save some money depending on the amount of work involved and what parts of the old system can be salvaged. According to Angi , you can expect to pay between $5,000 and $12,000 to replace the tank and drain field. The average cost lands at around $6,000.
Note that this is a general range based on costs reported directly to Angi by homeowners. If you have an exceptionally complex installation, your costs could exceed the top end of the range.
What factors affect septic tank installation costs?
A large concrete septic tank in the process of being installed in the ground
There's more than just the cost of the septic tank and labor that goes into the overall price of your system. Here's what to watch out for:
1) Septic tank size
The larger your home, the larger the septic tank you'll need because you have more sources, like sinks, toilets and bathtubs, feeding water into the system. The number of people living in your home also has a large impact. The Original Plumber & Septic , a plumbing company in Woodstock, Ga., recommends a 750-gallon tank for one- to two-bedroom homes and up to a 1,500-gallon tank for five- and six-bedroom homes. Other home sizes fall somewhere in between with 1,000- and 1,200-gallon tanks.
2) Septic tank material
Septic tanks come in three main materials: fiberglass, plastic and concrete. Plastic tanks tend to be the most affordable but are more susceptible to damage from nearby root systems and ground shifting. Concrete and fiberglass tanks are much more durable but cost more. Concrete tanks also require more heavy-duty equipment to install because of their weight.
Note that there may be regulations in your area regarding what types of tanks you can install. Check with your local permitting department for details.
3) Type of system
A septic system isn't just a tank in a hole in your yard; it also properly filters wastewater and breaks down organic material before and during draining. The two main types of systems are aerobic and anaerobic , referring to the type of bacteria they rely on to break down waste. Anaerobic systems are more affordable than aerobic ones, but they require a larger leach field, according to Angi .
The type of system you use depends on the size of your yard and the type of soil, so you should consult with your plumber before deciding on one system over the other. There may also be regulations for your area that dictate the type of system you must use.
4) Inspections and permits
Wastewater can be dangerous if it isn't properly disposed of, so you'll need to obtain a permit with approved plans to start your project. Once the system is installed, you'll typically have to have it inspected to ensure there are no issues and it adheres to local regulations. Both costs can vary widely depending on your location and local requirements.
5) Labor and landscaping
Along with the cost of the tank, labor and landscaping will be the largest chunk of the overall cost of your septic tank installation. Heavy equipment is required to dig the hole your tank will sit in, along with the trench used for the drainage field. Depending on obstructions and things like the pitch of your yard, this may be somewhat complex, further driving up costs.
Do you need a permit to install a septic tank?
In most cases, yes. According to the Environmental Protection Agency (EPA), you must usually go through your local health or environmental department to apply for a permit. This usually includes having your property inspected and paying a fee to acquire the permit. According to Angi, permits can vary from $450 to more than $2,000 depending on where you live.
How long do septic tank systems last?
An open septic tank in the yard, in the process of being pumped
The EPA estimates concrete tanks can last around 50 years or more, but older tanks may need replacing sooner due to less durable construction. Tanks made of materials like plastic and fiberglass may have similar lifespans, provided they aren't damaged by root systems or the ground shifting over time. If you have access to the warranty or lifespan estimates by your septic tank manufacturer, those should give you a good idea of how long you can expect the tank to last with proper upkeep.
Other parts of the system, like the leach field and pumps, may need to be replaced sooner. The EPA says pumps usually need to be replaced every 10 to 20 years. Leach fields are good for up to 30 years, though you can expect more issues with the field properly discharging wastewater into the ground the older it is.
Should you install a septic system yourself?
An open residential septic tank with its lid an safety cover removed
No. In most locations, regulations and building codes require septic systems to be installed by licensed professionals. Simply put, installing a septic tank system is not a do-it-yourself job and you likely don't have access to a lot of the equipment needed to do it properly. Additionally, only trained experts can determine the type of system you need and how to construct the leach field to ensure wastewater is drained correctly.
If you are considering some DIY plumbing projects, check out our guide to the most common plumbing problems for homeowners and how much they cost to fix.
