Oregon Expands Access to Accessory Dwelling Units as Housing Rules Evolve

Oregon continues to expand housing options through statewide policies that make accessory dwelling units (ADUs) easier to develop in many communities.

ADUs—sometimes called backyard homes, in-law units, or granny flats—are separate residential units located on the same property as a primary home. State housing officials identify ADUs as an important way to create additional housing choices for homeowners and renters.

Oregon Already Requires ADUs in Many Residential Areas

Oregon has had statewide ADU requirements for several years.

Under current law, cities with populations greater than 2,500 and counties with populations greater than 15,000 generally must allow at least one ADU for each detached single-unit dwelling in qualifying residential areas within an urban growth boundary.

Local governments can still establish reasonable rules concerning the siting and design of ADUs. However, those rules cannot require an additional off-street parking space for an ADU, except in certain circumstances involving vacation occupancies.

This statewide framework is intended to make it easier for homeowners to add smaller housing units while allowing local governments to maintain reasonable development standards.

ADU Size Rules Are Also Evolving

Oregon’s newer Housing Model Code provides for an ADU maximum floor area of 1,000 square feet.

The model code also includes an exception when an entire floor of an existing primary dwelling is converted into an ADU.

This means the commonly cited 800-square-foot limit should not be treated as a statewide maximum for every Oregon ADU.

Homeowners should always check their local jurisdiction’s current requirements before beginning a project because zoning, setbacks, building codes, utilities, and other site-specific requirements may still apply.

Housing Permit Reviews Are Also Being Streamlined

Oregon is separately taking steps to speed up residential development reviews.

Senate Bill 974, passed during the 2025 legislative session, establishes expedited review procedures for certain residential development applications. Among other provisions, it requires local governments or special districts to complete final review of final engineering plans for qualifying residential development within 120 days of submission.

The law becomes operative on July 1, 2026.

Although this is not a 60-day statewide ADU review requirement, it represents part of Oregon’s broader effort to reduce delays in housing development.

What This Means for Homeowners

For homeowners, an ADU can provide several potential benefits.

A properly permitted ADU may provide:

• Additional housing for family members
• A potential rental opportunity
• More flexibility for multigenerational households
• An option for aging family members
• Additional housing within established neighborhoods

However, homeowners should understand that building an ADU still involves permitting, building-code compliance, utilities, financing, and site-specific requirements.

Before starting construction, homeowners should contact their local planning and building departments to determine which rules apply to their property.

An Important Change for Planned Communities and HOAs

Oregon’s ADU policies also have implications for homeowners associations and planned communities.

Oregon law provides that certain provisions in planned-community governing documents can become void and unenforceable if they prohibit or unreasonably restrict housing—including ADUs—that is otherwise allowed under applicable zoning. The relevant provisions become operative January 1, 2027.

This is particularly important for HOA boards and community managers.

Associations should review their governing documents and make sure community rules are consistent with applicable state and local housing requirements.

What HOA Boards Should Consider

For communities affected by Oregon’s housing rules, boards and managers may want to:

• Review CC&Rs and architectural guidelines
• Understand local ADU requirements
• Update homeowner communication materials
• Establish a clear architectural-review process
• Coordinate with local permitting authorities when appropriate
• Make sure community rules do not conflict with state law
• Keep residents informed about changes affecting ADUs and housing

The goal is to maintain community standards while ensuring that association rules remain consistent with Oregon’s evolving housing laws.

What Buyers and Sellers Should Know

ADUs can also become an important consideration when buying or selling a property.

Buyers should determine whether an existing ADU is properly permitted and whether it complies with applicable zoning and building requirements.

Homeowners considering an ADU should also evaluate construction costs, financing, insurance, utilities, maintenance, and potential rental income before moving forward.

Rather than assuming an ADU will automatically increase property value or generate a specific rental discount, homeowners should evaluate the economics of their individual property and local market.

The Bottom Line

Oregon continues to expand housing options through statewide ADU requirements and broader efforts to streamline residential development.

The changes do not amount to a single July 2026 law establishing a universal 60-day ADU approval process. Instead, Oregon’s housing framework combines existing ADU requirements with newer laws designed to streamline certain residential development reviews and prevent unreasonable restrictions on housing.

For homeowners, developers, and HOAs, understanding the interaction between state law, local zoning, building codes, and community rules will be increasingly important as Oregon works to expand housing options.

Sources

For current information, homeowners and community associations should consult the Oregon Department of Land Conservation and Development, the Oregon Legislature, and their local planning and building departments. DLCD provides statewide guidance on ADUs and housing-choice policies.