Property Line Changes
See also: Land Use / Master Use Permit - Plat, Land Use Code
What Is It?
A property line change involves moving the property boundary between your property and the property next to yours. For instance, property owners may want to move the property line of a lot with a single-family house on it. This process is called a lot boundary adjustment, or an LBA.
You may want to move your property line to:
- Include a building, such as your garage, that does not fully lie on your property
- Resolve a boundary disagreement between you and another property owner
- Adjust existing lots so each are big enough to build on separately
You may not create a new lot by moving your property line.
- Tip 213B, Lot Boundary Adjustments
What Permits Do You Need?
You need a lot boundary adjustment permit to make changes to your property line. You can find more information about this permit, including a detailed customer Tip and how to apply on our Land Use / Master Use Permit - Plat webpage.
Research the Code
Your application will need to show us that moving your property line will still maintain lots that conform to our land use code in the Seattle Municipal Code (SMC) and our building codes. Our customer Tip 213B, Lot Boundary Adjustments, has additional information about the requirements, process, and our review. For the complete criteria of approval for the LBA, please consult the land use code (SMC 23.28).
Regulations that govern environmentally critical areas. If your lot is in an environmentally critical area (ECA), you must have a topographic survey that delineates the area on a drawing when you apply for a lot boundary adjustment.
Utility service. Your lot must meet our minimum levels of service for water, sewer, power, and fire access.
Fire separation distances. If you’re moving your property line, the line’s new location should be at least 5 feet from your neighborhood residential zoned home, garage, and accessory buildings. In most cases, your buildings’ walls and eaves must be fire rated if they are less than 5 feet from your property line’s new location and openings located in these walls are limited.
- Seattle Residential Code R302
- Tip 213B, Lot Boundary Adjustments
Should You Hire a Professional?
In some cases, and if your site is not in an ECA, you may create them if you can develop scaled drawings with lot lines, bearings, right-of-way information, building and lot line dimensions, and location of all utility services and trees. See examples in the Lot Boundary Adjustment form.
If you are not able to complete the documents yourself, please hire a licensed surveyor. A licensed surveyor typically creates the documents for your lot boundary adjustment application. They can use our example of the Auto CAD drawing.