Seismic Retrofit Evaluation
A seismic retrofit evaluation in Oregon checks what a home inspection can only partly see, and only Portland has adopted a prescriptive retrofit standard.
A seismic retrofit evaluation assesses sill bolting, cripple walls and water heater strapping against earthquake risk. Portland is the only Oregon jurisdiction with prescriptive retrofit standards. Water heater strapping is required statewide, and DOGAMI publishes the hazard map by address.
What a home inspection can see
Sill plate anchor bolts and cripple wall plywood are observable in an open crawlspace. Square plate washers suggest a retrofit; round washers suggest original construction. Torque and embedment are not observable.
Water heater strapping is the single most inspectable seismic item in any Oregon house. It is legally required statewide and fails constantly, so every general inspection should report it.
Portland stands alone
The Construction Contractors Board states that Portland is the only Oregon jurisdiction with prescriptive earthquake retrofit standards. Portland requires a permit for the work.
Elsewhere the building official decides, and some jurisdictions do not require a permit. The statewide residential code adopts no prescriptive seismic strengthening for existing wood-frame houses.
Start with the map
DOGAMI HazVu shows earthquake shaking, liquefaction and landslide hazard for a specific address. The hazard, not the age of the house alone, decides how much the evaluation matters.
Seller disclosure in ORS chapter 105 is the other document to read alongside it. What the seller knows about past retrofit work belongs there.
Asked and answered
Strengthening an existing wood-frame house so it stays on its foundation in an earthquake. That means bolting the sill plate, bracing cripple walls with plywood, and strapping the water heater. In Oregon only Portland has adopted prescriptive standards for this work. DOGAMI maps the hazard by address, and the strapping alone is required statewide.
It means the house has been bolted, braced or both so the structure and foundation move together. An inspector can observe some of it: square plate washers on sill bolts point to a retrofit, while torque and embedment cannot be seen. A retrofit is not a guarantee, and Oregon has no statewide prescriptive standard outside Portland.
The answer sits on the DOGAMI hazard map more than on the house. HazVu shows shaking, liquefaction and landslide hazard for the address. Portland is the only Oregon jurisdiction with prescriptive retrofit standards and a permit path. One item is not optional anywhere: water heater strapping is required statewide under OPSC 507.2 and fails constantly.
No Oregon agency publishes a current figure. The one state document with numbers, a CCB factsheet, is undated, cites a retired bulletin, and prices well below the 2026 market. This site quotes only its sentence about Portland standards. Quotes come from retrofit contractors and engineers, and Portland is the one jurisdiction with a defined prescriptive scope to price against.
Questions are taken verbatim from live Google People Also Ask results for this inspection type. Answers rest on Oregon rule text and the records cited above.