What Is Form 22S — Septic System Addendum in Washington Real Estate?
Form 22S is the Septic System Addendum used in Washington real estate transactions when a property is served by an on-site septic system instead of a public sewer.
This addendum allows the buyer to inspect the septic system, review system records, and confirm the system is functioning properly before completing the purchase.
Because septic systems are privately maintained and regulated at the county level, buyers must verify the system condition and compliance before closing.
Form 22S is typically attached to the Purchase and Sale Agreement (Form 21) and becomes part of the binding contract once mutual acceptance occurs.
Video: Form 22S Septic System Addendum Explained
Why the Septic Addendum Is Used
Homes with septic systems require additional due diligence because the system is privately owned and maintained by the homeowner.
Form 22S allows the buyer to verify:
- the septic system is functioning properly
- the system has been inspected
- the tank has been pumped if required
- the system complies with county regulations
These inspections help buyers avoid costly repairs after purchasing the home.
What the Septic Inspection Includes
When Form 22S is included in the contract, the buyer may perform a septic inspection.
A typical inspection includes:
System inspection
A licensed septic professional inspects the tank, drain field, and system components.
Pumping and tank inspection
The septic tank may be pumped so the inspector can examine the interior condition.
System records review
County records may be reviewed to verify the system design and approved bedroom capacity.
This information helps confirm the system is operating correctly.
What Happens If the Septic System Fails Inspection
If the septic inspection reveals problems, the buyer may have several options depending on the contract terms.
Possible outcomes include:
- requesting repairs to the septic system
- requesting system replacement
- negotiating credits toward repairs
- terminating the contract if major defects are discovered
Septic system repairs can be expensive, which is why this inspection is important during the due diligence period.
Why Septic Inspections Are Important in Washington
Septic systems are common in many areas of Washington, especially in rural and suburban communities.
In counties such as Snohomish County, septic systems must be inspected before property transfer in many situations.
Buyers should verify the system’s condition and confirm it supports the number of bedrooms advertised for the home.
How Form 22S Fits Into the Due Diligence Process
The septic addendum often works alongside other inspection steps such as:
- general home inspection
- well inspection for properties with private wells
- sewer scope inspections for homes connected to sewer
Together these inspections help buyers fully evaluate the property before closing.
You can explore the full library of Washington real estate process explanations here.
Bottom Line
Form 22S is the Septic System Addendum used in Washington real estate contracts when a property has an on-site septic system. It allows buyers to inspect the septic system and verify its condition before completing the purchase.
FAQ
What is Form 22S in Washington real estate?
Form 22S is the Septic System Addendum used in Washington real estate contracts when a property is served by a private septic system.
What does a septic inspection include?
A septic inspection evaluates the tank, drain field, and system components and may include pumping the tank to inspect its condition.
Are septic inspections required in Washington?
Many counties require septic inspections before property transfer when a home uses an on-site septic system.
Can a buyer cancel a contract if the septic system fails inspection?
Yes. Depending on the terms of the addendum, buyers may request repairs or terminate the contract if serious problems are discovered.
Who pays for septic repairs?
Septic repairs are typically negotiated between the buyer and seller after inspection results are reviewed.