Why additions affect septic
Septic systems are sized for the home they serve — typically by number of bedrooms. Adding bedrooms or a casita adds expected flow. Depending on the system and the rules, that may mean a bigger tank, a larger field, or a separate system.
Options
| Situation | Possible approach |
|---|---|
| Existing system has extra capacity | Connect to it, if allowed |
| Existing system at capacity | Enlarge the tank and/or field |
| Casita far from the house | A separate system, if permitted |
Plan early
Talk to us before plans are final. Where the casita goes can depend on where septic can go.
Septic questions
Can my casita share the house's septic?
Sometimes. It depends on capacity, distance and permit rules.
Does adding a bedroom require a septic upgrade?
It may. We'll check your current system's size.
Do additions need a septic permit?
Changes to the system generally do.