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March 26, 2024

ADU Laws and Regulations in Portland - 2024

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Overview of ADU Regulations in Portland

In Portland, Accessory Dwelling Units (ADUs) offer homeowners a way to add living space to their property. The City of Portland recognizes ADUs as important options to increase housing diversity and affordability.

Permit Application Process: Before one builds or converts a structure to an ADU, a permit is necessary. All forms related to the permit application can be accessed and submitted online.

Zoning Requirements: The local zoning code sets the standards that cover detached accessory structures, including ADUs. Portland’s zoning code, particularly Chapter 33.205, stipulates the additional requirements for ADU development.

Basics of ADU Standards:

  • Detached ADUs must match the primary residence’s design.
  • Size limitations are imposed, often relative to the lot or primary dwelling size.
  • Occupancy regulations can affect rental use.

Utility Connections: An ADU may need new connections for water, sanitary, or sewer services, requiring a contractor licensed for work in the public right-of-way. For establishing a sewer tap, one must connect with Environmental Services for appropriate permits.

Allowance on Property: In certain residential zones, property owners may have up to two ADUs, subject to lot size requirements and other standards outlined by the City's regulations, which can vary depending on zoning and the type of ADU planned— attached versus detached units.

Portland’s regulatory framework for ADUs is structured to facilitate their development while maintaining neighborhood compatibility and ensuring safe living spaces. It is imperative for property owners to closely adhere to these regulations to successfully integrate ADUs into Portland’s housing fabric.

Types of ADUs in Portland

In Portland, Accessory Dwelling Units (ADUs) come in several forms, each offering unique possibilities for adding livable space to a property. These units can be an excellent way to increase density and provide more housing options within the city.

Detached ADUs

Detached ADUs are stand-alone structures that are separate from the primary residence. These units can be up to 800 sq. ft. in size, providing ample living area for occupants. They are often found in the form of converted garages or newly constructed backyard cottages, giving homeowners the flexibility to use the space for family or as a rental unit.

Attached ADUs

Attached ADUs share at least one wall with the main house, making them an extension of the existing structure. This type of unit might manifest as a built-out section of the home or an above-garage apartment, seamlessly integrating with the primary residence while adding valuable square footage.

Basement ADUs

Basement ADUs transform the lower level of a home into a separate living space. In Portland, these basement units often require specific egress windows and ceiling height compliance to ensure safety and comfort for residents. These modifications not only create a functional dwelling but also can increase the overall value of the property.

Conversion ADUs

Conversion ADUs involve altering existing spaces, such as attics or workshops, into legally habitable accessory units. These conversions typically require compliance with building codes regarding fire resistance and ingress/egress, ensuring the space is both safe and functional for its inhabitants.

Zoning Regulations for ADUs in Portland

Portland's accessory dwelling unit (ADU) regulations are specifically detailed within the city’s zoning code, ensuring homeowners comply with local laws. These regulations are crucial for maintaining the character and structure of neighborhoods while accommodating the need for additional housing.

Residential Zoning Codes

In Portland, ADUs are permitted across various residential zones, each with particular requirements that govern how ADUs can be developed. The zoning standards focus on aspects such as the occupancy and the number of ADUs allowed on a single property. A critical reference is Chapter 33.205 of the Portland Zoning Code, which provides the foundation for ADU development in the city’s residential sectors.

Building Heights and Dimensions

The regulations regarding building heights and dimensions for ADUs are put in place to ensure they blend with the existing residential structures. These dimensions include limits on the ADU's size relative to the primary dwelling and restricting the overall height to preserve neighborhood scale and privacy. Specific measurements can be found in various sections of the city's zoning guidelines for accessory dwelling units, offering clear expectations for developers and homeowners.

Property Setbacks

Property setbacks outline the required distances between the ADU and the property lines and between the ADU and the primary dwelling. Residential zones have distinct setback requirements that must be adhered to, preserving open space and addressing concerns such as light access, privacy, and emergency response accessibility. Further detail on the precise setback requirements for ADUs in Portland is available in the city's zoning resources.

Building Codes and Standards in Portland

In Portland, adherence to established building codes and standards is crucial for the construction and maintenance of accessory dwelling units (ADUs). These regulations ensure that ADUs are safe, accessible, and equipped with the necessary utilities and services.

Structural Requirements

When building an ADU, one must comply with the Oregon Residential Specialty Code. This covers structural integrity, ensuring that the construction can withstand relevant environmental stressors. Every building permit application for an ADU requires a thorough review by a contractor or city official to confirm that the structural design aligns with the code.

  • Foundation: Must support the designated loads and be appropriate for soil conditions.
  • Framing: Follows the Oregon Residential Specialty Code for dimensional lumber, fasteners, and joins.

Utilities and Services

Utility services for ADUs in Portland must meet the standards for residential dwellings. This includes separate or shared systems for electrical, plumbing, and other services.

  • Electrical: Installed by a licensed electrician and inspected for compliance with safety standards.
  • Plumbing: Proper plumbing installations must ensure adequate water flow and sanitation according to local codes.

Safety and Accessibility

Safety features for an ADU are mandated by both local and state building codes to ensure protection for residents. Additionally, accessibility is a key aspect, with "visitability" features encouraged for inclusivity.

  • Fire Safety: A door between units needs to be rated with a minimum 20-minute fire resistance.
  • Windows: Must meet egress requirements for safety and provide adequate light and ventilation.
  • Accessibility: While not mandatory, features for visitability are recommended, such as no-step entrances and wider doorways.

Permitting Process for ADUs in Portland

Before starting an accessory dwelling unit project in Portland, understanding the permitting process is crucial. This includes applying for permits, considering system development charges, and adhering to inspection and approval procedures.

Applying for ADU Permits

To construct or convert a space into an ADU, one begins by applying for a permit through the Portland.gov residential permitting page. Complete and accurate forms are pivotal for a successful application. Once submitted, the City of Portland's Bureau of Development Services reviews the permit application against the zoning and building codes.

System Development Charges (SDC)

System development charges are fees assessed to new developments, including ADUs, to offset the impact on public infrastructure. However, Portland offers an SDC waiver program for ADUs that adhere to certain conditions, such as adding to the available housing stock and maintaining the ADU as owner-occupied or a month-to-month rental for a minimum of ten years.

Inspections and Approvals

After the ADU permit application is processed, inspections ensure the ADU construction complies with the relevant codes. This critical step involves multiple visits from inspectors who will verify if the ADU meets the safety and quality standards set forth by the Oregon Construction Contractors Board and Portland's building regulations. Following successful inspections, final approval is granted, and the unit can be legally occupied.

Utility and Service Connections in Portland

When constructing an Accessory Dwelling Unit (ADU) in Portland, property owners must comply with specific regulations pertaining to utility and service connections. These regulations are in place to ensure the safe and proper integration of the ADU with existing infrastructure.

Water and Sewer Services

For water supply connections, a water meter may need to be installed or upgraded to meet the requirements of the additional dwelling. The City of Portland mandates that the contractor engaging in this work must be licensed and bonded for operations within the public right-of-way. The process involves applying for a permit through the Bureau of Environmental Services to establish a connection to the public sewer system or to create a new sanitary sewer connection known as a "sewer tap."

If an ADU is not serviced by the public sewer, a septic system may be used. Regulations for septic systems necessitate a permit for either installing a new system or verifying that the existing one is adequate for the increased demand. In cases where a cesspool exists, decommissioning is often required by Environmental Services, following strict guidelines to protect the environment and public health.

Electrical and Gas Services

Electrical and gas connections for an ADU must safeguard the integrity of Portland's energy infrastructure. Electrical services need to be extended from the main house or from the municipal grid, with work performed by a qualified electrician. Permits must be secured beforehand, and all installations should comply with the city’s building codes to ensure the safety and efficiency of the service.

For gas services, a professional must assess the existing gas meter’s capacity to handle the additional load. In some scenarios, upgrading the meter or installing an additional one may be necessary. Natural gas hookups should be handled by certified technicians to avoid any safety hazards and guarantee compliance with local regulations.

Stormwater Management

Managing stormwater is an essential consideration for ADU development in Portland. Regulations require the implementation of proper stormwater disposal systems to prevent runoff issues that can affect the environment and infrastructure. Property owners might need to install systems that adequately manage stormwater on-site, like dry wells or rain gardens.

The Bureau of Environmental Services provides guidance on the most effective methods for stormwater management and details the necessary steps for obtaining the relevant permits. It is crucial for builders and homeowners to observe these regulations carefully, as proper stormwater management is not only a legal requirement but also supports sustainability efforts within the city.

ADUs and Property Considerations in Portland

Accessory Dwelling Units (ADUs) can significantly alter the financial and functional dynamics of a property. Understanding the implications for property taxes, property value, and occupancy is crucial for homeowners considering the development of an ADU.

Impact on Property Taxes

The addition of an ADU to a property often results in an increase in property taxes due to the enhancement in property utility and livable space. Homeowners should consult with the county assessor's office to comprehend how an ADU may affect their property taxes. In Portland, Multnomah County provides guidance on how ADUs can affect property taxes specific to the region.

Influence on Property Value

While the effect on property value can vary, well-designed ADUs generally enhance the overall value of the property by providing additional housing options. They can be seen as an investment that offers potential for both long-term rental income and increased property value. Prospective buyers often view ADUs as a flexible feature, allowing for a source of rental income or extended living space.

Occupancy and Usage Regulations

ADUs in Portland are subject to specific occupancy and usage regulations. For example, they must adhere to zoning requirements, which can affect the potential for short-term rentals versus long-term rentals. Detailed information about these zoning requirements can be found on the Portland government website. Additionally, the distinction between types of ADUs, such as detached versus attached units like duplexes, influences the regulations they are subject to and the potential uses they offer.

Parking and Accessibility in Portland

In Portland, accessory dwelling unit (ADU) regulations offer nuanced guidance on off-street parking and prioritize accessibility to accommodate both residents and visitors.

Off-Street Parking Requirements

Portland's zoning code contains provisions that waive the necessity for additional off-street parking when an ADU is constructed. For existing dwellings, any required parking must be retained or suitably replaced on the property. The specifics are outlined in Chapter 33.266 of the Portland Zoning Code. Nevertheless, it's important to note that while off-street parking isn't mandated for ADUs, maintaining or compensating for parking associated with the primary dwelling is a key compliance factor.

Accessibility for Residents and Visitors

The city of Portland values visitability and ensures accessible parking spaces are both available and effectively utilized. Property owners next to disability parking spots receive communication every two years to confirm ongoing usage. For further details, individuals can contact the Portland Bureau of Transportation (PBOT). This proactive approach emphasizes the city's commitment to accessibility.

ADU Design and Construction in Portland

Accessory Dwelling Units (ADUs) in Portland must comply with specific design and construction standards. These units offer an innovative solution to housing affordability and efficient land use when executed correctly.

Design Standards

The design of an ADU in Portland must adhere to the city's zoning requirements. The size and placement of ADUs are determined in relation to the primary structure, maintaining a balance between functionality and the existing neighborhood aesthetic. Interior design should optimize the limited space, focusing on light, storage, and living areas.

  • Minimum lot size requirements
  • Design that complements primary structures
  • Efficient interior layout

Construction Best Practices

It's crucial for the construction of ADUs to follow best practices in the industry, not only to ensure compliance with city regulations but also to maintain long-term affordability through reduced maintenance costs. Utilizing durable materials and quality craftsmanship can mitigate future expenses.

  1. Use of durable materials
  2. Quality craftsmanship
  3. Focus on long-term maintenance reduction

Working with Contractors

Working with experienced contractors familiar with Portland’s ADU construction costs and regulations can streamline the process. They should provide clear, itemized estimates and timelines to set realistic expectations. Transparency in cost and regular communication are key in managing an efficient construction project.

  • Select contractors with ADU experience
  • Expect transparent cost estimates
  • Emphasize clear communication for project timelines

Frequently Asked Questions

These questions address the latest laws and insights regarding ADUs in Portland, ensuring homeowners have accurate information.

What are the current setback requirements for constructing an ADU in Portland, Oregon?

Setback requirements for ADUs in Portland stipulate that detached structures must generally be at least 5 feet from side and rear property lines. However, for specific zones and configurations, there may be variations or additional conditions to consider.

How do the recent changes in Portland's ADU regulations affect homeowners?

Recent changes provide homeowners with more flexibility by allowing ADUs on smaller lots and removing the owner-occupancy rule for certain properties, which can enhance rental opportunities and increase the housing supply in the city.

What are the size and design restrictions for ADUs in Portland under the latest laws?

ADUs in Portland are limited in size to a maximum of 800 square feet or 75% of the primary dwelling's living area, whichever is less. Additionally, there are height restrictions and design standards that aim to maintain neighborhood character.

What are the specific permitting costs for an ADU in Portland as per the current regulations?

The permitting costs for an ADU in Portland can vary, but homeowners should plan for both a building permit fee and system development charges. These fees are subject to change, and it is best to consult the most current Portland government schedules for accurate figures.

How does building an ADU in Portland potentially impact property value?

Adding an ADU can increase the overall property value by enhancing its functionality and providing additional living space or rental income potential, although it depends on market trends and individual property assessments.

What incentives are available for ADU construction in Portland?

Portland has offered incentives such as waiving certain system development charges for ADUs subject to a 10-year commitment to housing availability, providing homeowners with an economic advantage to build these units.

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