ADU Rules in Bend, Oregon

Bend, the seat of Deschutes County and Central Oregon's largest city, is experiencing one of the most severe housing affordability crises in the Pacific Northwest. Situated along the Deschutes River in the high desert east of the Cascade Mountains, Bend grew from about 52,000 residents in 2000 to over 100,000 today, placing enormous pressure on housing supply. ADUs represent one tool for increasing housing density within the city's Urban Growth Boundary. Understanding Bend's unique combination of state law requirements, wildfire risk, irrigation infrastructure, and rapid growth is essential for any ADU project here.

Oregon Statewide ADU Law — Critical Context

Two Oregon laws are central to ADU rights in Bend:

Oregon HB 2001 (2019) requires cities with populations over 10,000 to allow middle housing — duplexes, triplexes, fourplexes, and cottage clusters — in all residential zones. Bend must comply, eliminating its ability to maintain single-family-only zoning throughout the city. This is particularly significant given Bend's housing crisis and rapid growth.

Oregon's statewide ADU framework is SB 1051 (2017) plus HB 2001 (2019) middle housing. HB 2098 (2021) is a rental-assistance bill, not ADU.

What Bend Allows

Under the Bend Development Code and state mandates, the following ADU types are permitted in residential zones:

• Detached ADU: A freestanding structure separate from the primary home, with independent kitchen, bath, and entrance.
• Attached ADU: An addition to the primary dwelling with a dedicated separate entrance and self-contained living facilities.
• Interior Conversion: Converting existing basement, attic, or interior rooms in the primary structure into a separate dwelling unit.
• Garage Conversion: Repurposing an existing detached or attached garage as habitable ADU space meeting Oregon habitability standards.

One ADU per single-family lot is permitted by right. Bend's updated code may allow additional density under HB 2001.

Size and Setback Standards

Oregon law prohibits Bend from requiring ADUs smaller than 900 square feet or 75% of the primary dwelling's floor area, whichever is less. Typical detached ADU setbacks in Bend's residential zones include:

• Rear setback: 5 feet minimum (more where canal setbacks apply)
• Side setback: 5 feet minimum
• Height: Generally 15–20 feet for detached ADUs

Wildfire Risk — WUI Construction Requirements

This is critical for Bend property owners. Large portions of Bend and surrounding Deschutes County are in designated Wildland-Urban Interface (WUI) zones — areas where development meets or intermingles with wildland vegetation. Oregon adopted statewide WUI construction standards following catastrophic 2020 Labor Day fires that destroyed thousands of structures statewide.

In WUI-designated areas, ADU construction must comply with:

• Fire-resistant exterior materials: Ignition-resistant siding, roofing, decking, and fascia
• Defensible space: Vegetation management zones around the structure (typically 30–100 feet)
• Ember-resistant vents: Protected vents and openings to prevent ember intrusion
• Oregon WUI building code: Mandatory fire-resistant construction standards

Check your property's WUI designation through the Oregon Office of State Fire Marshal or City of Bend Development Services before investing in ADU design. WUI requirements add cost but are legally required and potentially life-saving.

Irrigation Canal Setbacks

Bend has an extensive network of irrigation canals — particularly from the Central Oregon Irrigation District (COID) and other water users — running through residential neighborhoods. These canals typically require setbacks of 10 to 25 feet from the canal centerline or top of bank. An ADU proposed near a canal must account for these setbacks in the site design. Confirm canal locations and applicable setbacks with the City of Bend Development Services and your irrigation district.

Urban Growth Boundary

Bend has actively managed its UGB in coordination with Deschutes County and the Oregon DLCD. The UGB expansion process has been contentious given Bend's growth pressure. ADU permits apply only within Bend city limits and the current UGB. Properties outside the UGB in Deschutes County are subject to county rural land use regulations, typically Exclusive Farm Use (EFU) or Forest zones that do not permit ADUs.

Seismic Considerations

Central Oregon has lower seismic hazard than the Cascadia coast but is not seismic-free. New ADU construction in Bend must meet Oregon's current seismic building code standards. DOGAMI resources provide specific hazard maps for the Deschutes area.

Permit Process

Oregon's statewide ADU framework is SB 1051 (2017) plus HB 2001 (2019) middle housing. HB 2098 (2021) is a rental-assistance bill, not ADU.

Contact: City of Bend Development Services — (541) 388-5580 — bendoregon.gov/development-services

Disclaimer

ADU regulations in Bend — including WUI requirements — are subject to change and may be updated as Oregon continues housing reform. Canal setback requirements may vary by irrigation district. Always verify current standards with the City of Bend Development Services, Oregon Office of State Fire Marshal, and your irrigation district. This page is for informational purposes only and does not constitute legal or planning advice.