Portland, Oregon
ADU (accessory dwelling unit) in Portland
Portland allows accessory dwellings on many residential properties, subject to local siting, design, utility, and permit requirements. Wolf builds the modular home off site and manages the local placement work.
Where Wolf works
In Washington and Oregon, Wolf employees handle your project from property review and permits through construction, site work, delivery, and installation. Some projects require third-party services, such as surveys or septic design and installation, depending on the property and jurisdiction. Beyond Washington and Oregon, local contractors complete site work and utility connections.
Who it’s for
Who a Portland ADU can work for
Families housing parents, adult children, or guests
A detached backyard home keeps both households intact. On most Portland residential lots that is an ADU permit, not a remodel of the primary house.
Owners planning a long-term backyard rental
Oregon’s middle-housing reforms generally bar owner-occupancy and extra off-street-parking mandates for long-term ADUs. Short-term lodging follows different local rules.
Portland lot owners with delivery questions
Trees, alleys, parking pads, and trench length all shape the model choice. We start with the address and Portland’s local requirements.
What Wolf builds
What Oregon and Portland allow
Oregon law requires many cities to allow at least one ADU on qualifying residential lots inside an urban growth boundary, while Portland still applies local siting, design, utility, and permit requirements. Long-term ADUs in covered cities generally cannot be required to add owner occupancy or extra off-street parking, though short-term lodging can carry different conditions. System development charges may be a significant part of the project, and Portland has offered waivers or exemptions for some qualifying ADUs. We confirm current eligibility and costs for the property during the evaluation.
Factory home, Portland placement
Oregon BCD inspects the prefabricated structure. Portland inspects the site, foundation, and utility connections.
Exploring layouts for an inner-city property
Published plans run 307 to 1,232 sq ft. Compare the space you would use each day, then review the property before narrowing the layouts. Model B is available for City of Portland projects only.
A property-specific installed cost
Prices for the homes themselves range from $67,500 (Model B, City of Portland only) to $178,500 (Model I), with appliances separate. Your complete project is quoted after reviewing the property and confirming the scope. Installation and site work are quoted for your property. Permitting service and local fees are confirmed in your agreement. Portland SDCs can change the total significantly, so we confirm the current waiver status during the property evaluation.
Process
Portland permit path, in order
- 1
What it is
A second complete dwelling on a lot that already has (or will have) a primary home. Detached is Wolf’s product.
- 2
When it is legal
The lot must allow an ADU under ORS 197A.425 and meet Portland standards for setbacks, height, lot coverage, parking, and trees.
- 3
Typical size
Most backyard ADUs we discuss in the metro are 307–616 square feet. Larger plans require enough buildable area and a workable delivery route.
- 4
What Wolf handles
Wolf employees handle the project from the free evaluation and permits through factory construction, foundation, delivery, utility connections, and installation. We bring in third-party specialists when the property or jurisdiction requires them.
Models
Plans for Portland lots
Compare floor plans on the models page. The starting price covers the home itself; appliances and installation are separate. You can purchase our appliance package or provide your own. We price site work after seeing the property.
Notice the rooms and details you would use. These are layouts to explore; we need to review your property before recommending one.
Model B — City of Portland (only) — 307 sq ft
City of Portland (only)City of Portland (only). A compact one-bedroom; suitability needs a property review.
Model K — 432 sq ft
A one-bedroom layout with a separate living space; not a site-fit recommendation.
Model J — 828 sq ft
Two-bed, two-bath when the lot and the household need it.
Questions
Frequently asked questions
Does Portland automatically approve every ADU?
Are SDCs waived for a Portland ADU?
Where can I find Portland site notes and model fit?
Can I use the ADU as a vacation rental?
Keep reading
Related Wolf pages
See what your Portland property can support
Send the address and how you would use the unit. We will check Portland zoning, access, utilities, and a model that can be permitted as a dwelling.
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