01
Unit Lot vs. Condo vs. Lot Split
| Unit lot subdivision | Condominium | Standard short plat (lot split) | |
|---|---|---|---|
| What the buyer owns | Land under the home + the home | Airspace unit + share of common elements | A full conforming lot |
| Each lot must meet zoning on its own | No — the parent lot does | N/A | Yes |
| Best for | Townhomes, cottages | Stacked units (fourplex, stacked flats) | Lots big enough to split into two full lots |
| Builder warranty exposure | Standard residential | Higher under Washington condominium law | Standard residential |
| Lender preference | Strong | Varies | Strong |
02
The Steps
- 01Site plan showing the parent lot, each unit lot and shared areas.
- 02Preliminary unit lot plat submitted to the city, often with the building permits.
- 03Easements and agreements for shared driveways, utilities, walls and landscaping.
- 04Survey and final plat prepared by a licensed land surveyor once foundations are in.
- 05Recording with the Snohomish County Auditor or King County Recorder's Office; each unit lot receives its own tax parcel number.
03
Things That Trip Up Unit Lot Projects
- Utility service lines that cross another unit lot without an easement.
- Shared walls drawn on the plat that do not match the as-built walls.
- No maintenance agreement for the driveway — a common lender objection.
- Notes on the plat that limit future additions, which buyers should know about.
04
Unit Lot FAQ
QCan I do a unit lot subdivision on an existing duplex?
If the duplex is side-by-side with a code-compliant fire wall and separate utilities, often yes.
QDoes each unit lot need street frontage?
No. Access through a recorded easement over a shared drive is normal.