Accessory Dwelling Units (ADUs) are redefining residential density and investment strategy in Portland. Whether you're looking to generate rental income, house multi-generational family members, or increase your property's equity, ADUs offer unparalleled flexibility. ACGI brings 4 generations of structural expertise to every ADU project.
Standard ADU Classifications
1. Detached ADU (DADU)
A standalone structure in the backyard. Offers maximum privacy and rental appeal but requires the highest upfront investment due to new foundation and utility lateral requirements ($180k - $315k+).
2. Internal Conversion (Basement/Attic)
Utilizing existing structural envelopes is the most cost-effective path to an ADU. Key challenges include ceiling height compliance, egress window installation, and moisture mitigation in Portland's high water table environments ($75k - $150k+).
3. Garage Conversion
Transitioning underutilized vehicle storage into high-value living space. Portland unique zoning allows for garage conversions without replacement parking requirements, making this a popular choice ($90k - $170k+).
Portland ADU Regulations
- No Parking Required: A major cost-saving regulation specific to the Portland metro area.
- Siting & Setbacks: Typically 5-foot side/rear setbacks with a 20-foot height limit for detached units.
- System Development Charges (SDCs): Current waivers may apply for units under certain size thresholds—check with BDS during pre-design.
The Financial Architecture of ADUs
A well-constructed ADU in Portland can command rents between $1,200 and $2,500 per month, often paying for its own construction financing while simultaneously increasing property value by six figures.
