If you are buying a cabin in the Smoky Mountains, there is a good chance it is on a septic system, not city sewer. That is normal for mountain and rural property, and a septic system that is sized right and maintained can serve a home for decades. But it changes what you need to check before closing, especially if the cabin will be an overnight rental.
Insight Home Inspection Services has performed 5,000+ inspections across Tennessee since 2014, including cabins and rural homes around Sevierville, Pigeon Forge, and Gatlinburg, Maryville and Townsend, and Athens and Monroe County. Here is what buyers should understand about each system.
The Difference in Plain Terms
City sewer. Wastewater leaves the house through one main pipe and flows to a public sewer line. The utility treats it. You pay a monthly bill. Your responsibility ends where your pipe meets the public line, but that pipe, from the house to the street, is yours to repair.
Septic. Wastewater leaves the house through one main pipe and flows to a tank buried on the property. Solids settle in the tank. Liquid flows out to a drain field, where the soil filters it. There is no monthly bill, and there is no utility. The owner is responsible for the whole system.
| City sewer | Septic | |
|---|---|---|
| Who maintains it | The utility, past your property line | The owner, all of it |
| Monthly bill | Yes | No |
| Routine upkeep | None for most owners | Tank pumped on a regular schedule |
| Capacity limit | Rarely an issue | Sized for a set number of bedrooms |
| Biggest repair risk | The buried line to the street | The drain field |
How to Tell Which One a Property Has
Do not rely on the listing alone. Confirm it:
- Ask the seller or listing agent in writing. Ask for the septic permit and pumping records if it is on septic.
- Check the utility bill. A sewer charge on the water bill means city sewer.
- Check county records. The county environmental health office keeps septic permits on file.
- Look at the lot. Tank lids, risers, or a cleared, grassy area downhill from the cabin often mark the tank and drain field.
The Question That Matters Most for Rental Cabins
A septic system is permitted for a set number of bedrooms. That number is based on how much wastewater the soil on that lot can handle.
Rental cabins are often advertised by how many people they sleep, not by how many bedrooms the septic permit allows. A cabin permitted for two bedrooms and listed as "sleeps 10" is putting far more water through the system than it was built for. That shortens the life of the drain field, and it can create a problem with the county.
Before you close, compare three numbers:
1. Bedrooms on the septic permit
2. Bedrooms in the listing
3. Occupancy in the rental listing
If they do not line up, ask why before you buy, not after.
What a Home Inspector Checks on a Septic Property
It helps to know exactly what is and is not covered.
What Insight checks
- Visible septic components
- Signs of drain-field trouble, such as soggy ground, standing water, or sewage odor
- How the drains and toilets perform inside the cabin
- With a sewer scope, the inside of the main waste line from the cabin to the tank, by video camera
What a home inspection does not include
- Pumping the tank
- Opening and inspecting the inside of the tank
- Testing the drain field's capacity
For those, you need a licensed septic contractor. On any septic property, we recommend having the tank pumped and inspected by a septic contractor before closing. We can point you to one.
Why the Line to the Tank Deserves a Camera
The pipe between the cabin and the tank is buried, and on a mountain lot it often runs downhill through tree roots and rocky ground. Problems in that line cause backups inside the cabin, and they cannot be seen from the surface.
A sewer scope finds:
- Tree roots growing into the line
- Sags where waste collects
- Cracks, breaks, and separated joints
- Blockages
The same is true for cabins on city sewer. The line from the house to the street belongs to the owner, and replacing it is one of the more expensive repairs a homeowner can face. A sewer scope is a $200 add-on to any Insight inspection.
Questions to Ask the Seller
If the cabin is on septic
- Where are the tank and the drain field?
- How many bedrooms is the system permitted for?
- When was the tank last pumped? Are there records?
- Has the system ever backed up or been repaired?
- Has anything been built or parked over the drain field?
If the cabin is on city sewer
- How old is the line to the street, and what is it made of?
- Have there been any backups or slow drains?
- Has the line ever been repaired or replaced?
Other Checks for Mountain Property
Cabins outside city limits often have more than one private system. If the property has a well, add a well water test. East Tennessee geology also makes a radon test worth doing on any purchase. For the full list, read what your cabin inspection needs to cover.
FAQ
Is septic or sewer better for a cabin?
Neither is better on its own. City sewer has a monthly bill and less upkeep. Septic has no monthly bill, but the owner is responsible for pumping and repairs, and the system has a capacity limit. Most mountain cabins do not have a choice, because public sewer does not reach them.
Does a home inspection include the septic system?
A home inspection covers visible septic components and signs of drain-field trouble. It does not include pumping the tank or inspecting inside it. A licensed septic contractor does that. Insight can also run a camera through the main waste line to the tank with a sewer scope.
How do I find out how many bedrooms a septic system is permitted for?
Ask the seller for the septic permit, or request it from the county environmental health office. The permit lists the number of bedrooms the system was designed to serve.
Can a sewer scope be done on a home with a septic system?
Yes. The camera inspects the main waste line from the home to the septic tank and shows root intrusion, sags, breaks, and blockages in that line.
What are the signs of a failing septic system?
Common signs include slow drains throughout the house, sewage odor outdoors, soggy ground or standing water over the drain field, and unusually green grass in one area of the yard. Any of these should be checked by a septic contractor before closing.