Order a site survey

What you're getting

Portland accepts a boundary + topographic survey as the base for your permit site plan. The surveyor stakes your property corners, locates the structures and utilities visible above ground, and hands you a stamped drawing.

You don't need a full ALTA/NSPS survey for a DADU. A boundary-and-topo is enough, and cheaper.

What the surveyor delivers

• Property lines with corner monuments shown
• Existing structures with measurements to the property lines — this is what proves your setbacks
• Existing trees ≥12" DBH (ask explicitly; not every surveyor includes this by default — that's the threshold under Title 11.50)
• Existing utilities visible above grade (meters, manholes, cleanouts)
• One-foot topo contours
• Both PDF and DWG so your designer can build on the DWG

How to choose one

• Confirm the surveyor is licensed by the Oregon State Board of Examiners for Engineering and Land Surveying before you sign.
• Ask if they've done Portland DADUs recently — they should know what PP&D expects.
• Put the DWG file in the contract scope. Designers will charge you to redraft from a PDF.

When you can skip it

Almost never. A few pre-approved plan workflows let you skip a full survey if the existing house was recently surveyed and your DADU is in an obviously conforming spot. The fee is small compared to the cost of a setback violation discovered mid-build.