What to know before buying a house with a septic system

Buying a house with a septic system is normal in rural and many suburban areas. The key is to learn the system’s age, size, history and condition before you are committed. In practice that means three things: request the records, ask the seller direct questions, and make your offer contingent on a full septic inspection.

Questions to ask the seller

Virginia Cooperative Extension and EPA suggest asking about these. Get the answers in writing if you can.

1. Is the house on a septic system or public sewer? Do not assume. Confirm with the health department.
2. Where are the tank, its lids and the drain field? The owner should know. If not, the health department may have a drawing.
3. What type of system is it? A conventional gravity system needs little upkeep. Systems with pumps, dosing or advanced treatment need more care and often a service contract.
4. When was the tank last pumped and inspected? If the owner does not know, plan on pumping and inspecting before closing.
5. Has the system ever failed or been repaired? Why? A broken baffle that was fixed is minor. A drain field that had to be moved or replaced deserves more questions.
6. Has the house been remodeled or had bedrooms added? Systems are sized by bedrooms or daily flow. An addition without a larger system can overload it.
7. Is there a reserve drain field area? This is land set aside for a future replacement field. Without one, a future repair can be much more expensive.
8. Is there a service contract, alarm or pump? Ask for the manuals and service company.

If you want background before you talk to the seller, see what a septic system is and how it works and the types of septic systems.

Records to request

Record	Where to get it	What it tells you
Permit and as-built drawing	Local health or environmental department	Installation date, tank size, location of parts, sometimes soil data
Pumping receipts	Seller	How often the tank was pumped and how full it was
Past inspection reports	Seller or health department	Sludge levels, defects found, repairs recommended
Repair permits and failure history	Health department	Whether the system has failed before and how it was fixed
Service contract and manuals	Seller	Required upkeep for pumps, alarms or treatment units

EPA notes that the as-built drawing and permits can show when the system was installed and the soil it sits in. That matters because, according to EPA, a drain field older than about 25 to 30 years can lose capacity as the biomat (a slimy layer that forms in the soil under the trenches) thickens.

The septic inspection contingency

An inspection contingency lets you renegotiate or walk away if the septic inspection turns up problems. A few points to get right:

• Order a full inspection, not a visual one. The tank should be opened, sludge and scum measured, baffles checked, and the distribution box and drain field evaluated. EPA lists all of these as part of a thorough inspection. See what a septic inspection includes.
• Allow enough time. Lids may need to be found and dug up. Build in time for scheduling and a written report.
• Choose the inspector yourself when the law allows, and confirm they hold whatever license or certificate your state or county requires.
• Be there. You will learn where everything is, which you will need later.

States and counties that require inspection at sale

Rules vary widely, and many states leave it to counties. EPA says that in many states a septic system must be inspected when real estate changes hands. A few verified examples:

Place	Rule
Massachusetts	Title 5 requires a septic inspection by a certified inspector within two years before a sale, or three years if the system has been pumped annually. If weather prevents it, the inspection can happen up to six months after the sale with written notice to the buyer.
Arizona	The seller must hire a qualified inspector within six months before the transfer, and give the buyer the report and system records before closing. The buyer files a Notice of Transfer within 15 days after.
Delaware	Regulations effective Jan. 11, 2014 require inspection of all septic systems before property transfers.
Minnesota	State law requires written septic disclosure at sale. An inspection at sale is not a statewide requirement, but some counties require one; Goodhue County has since Oct. 1, 2014.

This is not a complete list. Other states and many counties have their own rules, and they change. Call the county health department where the house is located and ask what is required at transfer, then confirm with your agent or attorney.

Red flags

Walk the property yourself before the inspection. Virginia Cooperative Extension and EPA list these warning signs:

• Standing water, soggy ground or a sewage smell over the drain field
• Grass over the drain lines that is much greener than the rest of the yard, especially in dry weather (drought or low fertility can also cause this, so have a professional check)
• Slow drains or gurgling plumbing inside the house
• A drain field that was moved or replaced in the past
• No reserve area for a future drain field
• More bedrooms than the permit allows, or additions built after the system was installed
• Driveways, patios, sheds or large trees on top of the drain field
• No pumping records at all
• Alarms or pumps that the seller cannot explain

None of these alone means you should walk away. Each one means you need a clear answer before you close.

What to budget after you buy

A septic system has no sewer bill, but it has its own costs. Plan for these, based on EPA guidance:

Item	How often	Notes
Pumping	Typically every 3 to 5 years	Depends on tank size and household size
Professional inspection	At least every 3 years	About once a year for systems with pumps or other mechanical parts
Service contract	Yearly	Common for advanced treatment and alternative systems
Pumps and controls	Replace every 10 to 20 years	Only on systems that have them
Tank	Concrete tanks can last 50 years or more	Plastic tanks can have similar lifespans; check the maker’s estimate

The pumping frequency calculator estimates your interval from tank size and household size, and the septic system maintenance guide covers the rest of the routine.

Negotiating septic repairs

If the inspection finds problems, get a written repair estimate, ideally from a company other than the one that did the inspection. Then decide how to handle it:

• Seller repairs before closing. Ask for permits, receipts and a final inspection showing the work passed.
• Price reduction or closing credit. Useful when you want to choose the contractor. Base the amount on written bids.
• Escrow holdback. Part of the seller’s proceeds is held until repairs are done. Ask your lender and attorney whether this is allowed for your loan.
• Walk away. If the drain field has failed and there is no suitable replacement area, the fix may be an expensive alternative system.

In Massachusetts, a system that fails Title 5 generally must be repaired or upgraded within two years of the inspection, which affects who pays and when. Rules elsewhere differ.

To get a sense of what a repair might cost before you negotiate, see the drain field replacement cost guide. After you move in, keep every pumping and inspection record. EPA recommends a professional inspection at least every three years for a typical system, and you will be the seller one day.