ADU Regulations at a Glance
Gresham ADU Rules & Regulations
Oregon State ADU Laws
Oregon has embraced ADU-friendly legislation to address housing needs. State law requires cities to allow ADUs on single-family residential lots.
Key Oregon ADU Regulations:
- Size Limits: Typically up to 800-900 sq ft, depending on local jurisdiction.
- Parking: Many Oregon cities have eliminated parking requirements for ADUs.
- Owner Occupancy: Oregon law limits owner-occupancy requirements.
- Approval Timeline: Streamlined permitting processes in most jurisdictions.
Gresham Local Requirements
GatherADU works with Gresham homeowners to navigate local building codes and zoning requirements specific to your property and neighborhood.
Your Rights Under California Law
California law (AB 68, AB 881, SB 9, and subsequent legislation) guarantees your right to build ADUs. Cities cannot:
- Require owner-occupancy for ADUs permitted after 2020
- Require additional parking for ADUs near transit
- Charge impact fees for ADUs under 750 sq ft
- Deny ADUs that meet state minimum standards
- Impose lot coverage limits that prevent a 800 sq ft ADU
If you believe your ADU application is being unfairly denied, California HCD can intervene on your behalf.
This information is for informational purposes only and does not constitute legal advice. Consult a qualified attorney for legal guidance.
California State ADU Rules
Oregon ADU Legislation Overview
Oregon has been at the forefront of ADU-friendly legislation, recognizing ADUs as an important housing solution.
Key Oregon ADU Laws:
- HB 2001 (2019): Required cities to allow ADUs on all single-family residential lots.
- SB 458 (2021): Allowed lot splits for homes with ADUs.
Oregon ADU Benefits:
- Streamlined approval process
- Limited parking requirements
- Flexible rental options
About Gresham
Gresham is a vibrant community located in Oregon with a population of approximately 113,525. As demand for housing continues to grow, accessory dwelling units (ADUs) have become an increasingly popular solution for homeowners looking to add living space, generate rental income, or house family members.
GatherADU provides comprehensive ADU services to Gresham residents, including custom design, permit assistance, and full construction management. Our team understands local building codes and zoning regulations to ensure your project proceeds smoothly.
More About Gresham
Gresham, Oregon, is a city located in Multnomah County, part of the Portland metropolitan area. Known for its scenic beauty, suburban charm, and close-knit community, Gresham has a population of approximately 113,525 residents. The city offers a blend of urban convenience and natural surroundings, making it a desirable location for many families and individuals.
Geography and History
Gresham is situated about 15 miles east of Portland, with easy access to both urban amenities and natural landscapes. The city was incorporated in 1905 and has grown from a small agricultural town into a significant suburban community. Its location along the base of the Cascade Range and proximity to the Columbia River add to its appeal.
Local Economy
Gresham’s economy is diverse, with key sectors including:
- Retail and Services: Includes shopping centers, local businesses, and a variety of service providers.
- Healthcare: Features facilities such as Legacy Mount Hood Medical Center.
- Education: Home to schools within the Gresham-Barlow School District and several higher education institutions.
- Manufacturing and Industry: Includes various industrial and distribution centers contributing to local employment.
- Recreation and Tourism: Offers parks, recreational facilities, and access to outdoor activities in nearby natural areas.
Popular Neighborhoods
Gresham offers several neighborhoods, each with unique characteristics:
- Downtown Gresham: Known for its historic charm, local shops, and community events.
- Rockwood: A diverse area with a mix of residential and commercial developments.
- Woodland Park: Features suburban homes and family-friendly amenities.
- Powell Valley: Offers a blend of rural and suburban living with access to natural landscapes.
- Pleasant Valley: A residential area with newer homes and proximity to local services.
Real Estate Market
Gresham’s real estate market includes a variety of single-family homes, townhouses, and multi-family properties. The market has seen growth due to the city’s appeal as a more affordable alternative to Portland and its surrounding areas. New construction projects and residential developments are common as the city continues to expand.
ADU Regulations in Gresham
Gresham’s ADU regulations are designed to comply with Oregon state laws while accommodating local preferences and needs.
- Zoning: ADUs are permitted in residential zones, including single-family and multi-family districts. Some mixed-use zones may also allow ADUs.
- Types of ADUs: Both attached and detached ADUs are allowed, as well as Internal ADUs (IADUs) and Detached ADUs (DADUs).
- Size Limits:
- Detached ADUs: Up to 800 sqft for standard lots; up to 1,000 sqft on larger lots.
- Attached ADUs: Up to 50% of the primary dwelling’s living area or 800 sqft, whichever is less.
- IADUs: Integrated into the primary dwelling, with no specific size limit if part of the overall home.
- Height Restrictions: Detached ADUs are generally limited to 18 feet in height, though exceptions may be made based on design and site-specific conditions.
- Parking: Typically, one additional parking space is required for an ADU. Parking requirements may be waived if the ADU is located near public transit or if the primary residence is within an existing development with adequate parking.
- Owner Occupancy: There is no owner-occupancy requirement for ADUs in Gresham, allowing flexibility in rental options.
- Approval Process: ADUs meeting certain criteria can benefit from a streamlined approval process, facilitating quicker permitting and construction.
- Multiple ADUs: In multi-family properties, up to two detached ADUs are allowed, or ADUs for 25% of the existing units within the structure, whichever is greater.
- Impact Fees: Impact fees for ADUs are typically reduced to encourage development and affordability, particularly for smaller units.
- Design Standards: ADUs must be designed to be compatible with the primary residence and neighborhood character, including considerations for architectural style and aesthetics.
These regulations are designed to support Gresham’s housing needs while maintaining its suburban charm and enhancing community development.
Cultural Landmarks and Unique Aspects
Gresham is known for several unique aspects and cultural landmarks:
- Gresham History Museum: Showcases local history and heritage through exhibits and artifacts.
- Powell Butte Nature Park: Offers trails and outdoor activities with scenic views of the surrounding landscape.
- Gresham’s Historic Downtown: Features preserved historic buildings and local shops, reflecting the city’s heritage.
- Blue Lake Regional Park: Provides recreational opportunities including a lake for swimming, picnicking, and hiking trails.
- Gresham Art Committee: Promotes local arts through various events and public art projects.
Gresham’s ADU regulations are designed to address the city’s housing needs while preserving its suburban character and supporting community growth. With its diverse economy, cultural landmarks, and range of neighborhoods, Gresham offers a desirable living environment in the Portland metropolitan area. The city’s approach to ADU development reflects its commitment to providing flexible and affordable housing solutions while enhancing the overall quality of life for its residents.
Get Your Free Gresham ADU Feasibility Report
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Types of ADUs You Can Build in Gresham
California law allows several types of accessory dwelling units on residential properties. Understanding your options helps you choose the best approach for your property and goals.
Detached ADU
A standalone structure built separately from your main house, typically in the backyard. Detached ADUs offer maximum privacy for both homeowners and tenants, with their own entrance, walls, roof, and complete living facilities. In Gresham, detached ADUs can be up to 1,200 square feet and 16 feet tall. This option provides the most flexibility in design and placement, though it typically costs more than conversions due to new construction requirements.
- Max Size: Up to 1,200 sq ft
- Height: Up to 16 feet
- Setbacks: 4 ft from side/rear lines
- Best For: Maximum rental income, privacy
Attached ADU
An addition built onto your existing home, sharing at least one wall with the primary residence. Attached ADUs are often more cost-effective than detached units because they can leverage existing foundation, roof structure, and utility connections. They work well on properties with limited backyard space or where you want to minimize the visual impact of new construction. Many homeowners choose attached ADUs for aging parents who want proximity while maintaining independence.
- Max Size: Up to 1,200 sq ft
- Height: Matches main home
- Setbacks: Same as main structure
- Best For: Limited lot space, family housing
Garage Conversion ADU
Transform your existing garage into a complete living space. Garage conversions are often the most affordable ADU option in Gresham because the basic structure already exists. You save on foundation, framing, and roofing costs while creating a valuable rental unit or family living space. California law prohibits cities from requiring replacement parking when you convert a garage to an ADU, making this option particularly accessible. Most garage conversions result in studios or one-bedroom units ranging from 400 to 600 square feet.
- Typical Size: 400-600 sq ft
- Timeline: 3-5 months typical
- Cost: 30-50% less than new construction
- Best For: Budget-conscious, quick timeline
Junior ADU (JADU)
A smaller unit of up to 500 square feet created within your existing home's footprint, typically by converting a bedroom, basement, or attached garage. JADUs must include a cooking facility (at minimum, a sink, counter, and small appliance outlet) but can share a bathroom with the main house. In Gresham, you can build both a JADU and a full ADU on the same property, maximizing your housing options. JADUs require owner-occupancy in either the main house or the JADU itself.
- Max Size: 500 sq ft
- Location: Within existing home
- Requirements: Owner-occupancy required
- Best For: Minimal construction, family use
Above-Garage ADU
Build a new living unit above your existing or new garage structure. This two-story approach preserves your parking while adding living space above. In Gresham, above-garage ADUs can reach 18-20 feet in height depending on distance from property lines. This option is particularly popular in neighborhoods with narrow lots where backyard space is limited. The elevated position often provides better views and natural light than ground-level units.
- Max Size: Up to 1,200 sq ft
- Height: Up to 18-20 feet
- Parking: Preserved below unit
- Best For: Limited lot space, maintaining parking
Basement Conversion
While less common in Southern California due to construction patterns, properties with existing basements can convert that space into an ADU. Basement conversions require proper egress windows, adequate ceiling height (at least 7 feet in habitable areas), and may need waterproofing and ventilation upgrades. When properly executed, basement ADUs provide naturally cool living space and complete separation from the main home's daily activities.
- Max Size: Existing footprint
- Requirements: Egress, ceiling height
- Benefits: Cool temps, full separation
- Best For: Existing basements only
Complete ADU Services in Gresham
From initial feasibility analysis through final inspection, we handle every aspect of your ADU project. Our Gresham-focused approach ensures your project meets all local requirements while maximizing value.
Feasibility Analysis
We begin every project with a comprehensive analysis of your property's ADU potential. Our team reviews your lot size, zoning, setbacks, utility connections, and neighborhood context to determine what you can build. In Gresham, this includes understanding any overlay zones, historic district requirements, or other local factors that might affect your project. You receive a detailed report showing your options, estimated costs, and potential rental income before committing to design work.
- Property zoning verification
- Setback and lot coverage analysis
- Utility capacity assessment
- Cost and ROI projections
Design & Architecture
Our design team creates ADU plans tailored to your property and goals. Whether you want a modern studio for maximum rental income or a two-bedroom unit for family members, we design spaces that work. We understand Gresham architectural context and create designs that complement existing homes while meeting all building code requirements. Every design includes structural engineering, Title 24 energy compliance, and all documentation needed for permits.
- Custom floor plan development
- 3D renderings and visualizations
- Structural engineering
- Energy compliance documentation
Permitting & Approvals
Navigating Gresham permitting can be complex, but we handle it all. Our team prepares complete permit applications, manages plan check submissions, and coordinates with building department staff to address any comments or corrections. We track your application through the approval process and keep you informed of progress. Our experience with Gresham regulations helps avoid common pitfalls that delay other projects.
- Complete permit application prep
- Plan check management
- Building department coordination
- Permit tracking and updates
Construction
Our licensed construction team builds your ADU with quality materials and skilled craftsmanship. We handle all aspects of construction including foundation, framing, electrical, plumbing, HVAC, insulation, drywall, flooring, cabinets, and finishes. Throughout the build, we coordinate required inspections, manage subcontractors, and keep you updated on progress. Our goal is delivering a finished ADU that exceeds your expectations while respecting your timeline and budget.
- Licensed general contractor
- Quality materials and finishes
- Inspection coordination
- Project management and updates
Interior Design
A well-designed interior maximizes both livability and rental appeal. Our interior design services help you select finishes, fixtures, and colors that create appealing spaces within your budget. We offer curated finish packages at different price points, or work with you to customize selections. From kitchen layouts that maximize counter space to bathroom designs that feel spacious, we sweat the details that make small homes work beautifully.
- Finish and fixture selection
- Space planning optimization
- Curated design packages
- Custom interior options
Financing Guidance
We help connect you with financing options suited to your situation. Many Gresham homeowners use home equity, construction loans, or specialized ADU financing products to fund their projects. We can introduce you to lenders experienced in ADU financing and help you understand options including cash-out refinancing, HELOCs, and construction-to-permanent loans. While we're not lenders ourselves, our guidance helps you navigate financing decisions confidently.
- Financing option overview
- Lender introductions
- ROI and cash flow projections
- Budget planning assistance
How We Build Your Gresham ADU
Our streamlined process takes you from initial concept to move-in ready ADU. Here's what to expect at each stage of your project.
Free Consultation
We start with a free consultation to understand your goals, assess your property, and explain your options. This can happen via phone, video call, or an in-person site visit in Gresham. You'll learn what you can build, approximate costs, and timeline expectations.
Feasibility Study
Our team conducts a thorough analysis of your Gresham property. We verify zoning, calculate setbacks and lot coverage, assess utility connections, and identify any site-specific considerations. You receive a written report with your ADU options.
Design Development
Working with our architects and designers, you'll develop floor plans, select exterior styles, and make finish selections. We create 3D renderings so you can visualize the finished ADU before construction begins.
Permitting
We submit your complete permit application to Gresham and manage the entire approval process. This includes responding to plan check comments and coordinating with building department staff through to permit issuance.
Construction
With permits in hand, construction begins. Our crews work efficiently while respecting your property and neighbors. For a typical Gresham ADU, construction takes 4-6 months. You'll have a dedicated project manager throughout the build.
Walkthrough & Move-In
We conduct a detailed walkthrough, demonstrate systems and appliances, and address any punch list items. Once final inspections are complete, you receive your certificate of occupancy. Your new Gresham ADU is ready.
ADU Costs in Gresham
Understanding ADU costs helps you plan realistically and evaluate the investment opportunity. Here's what to expect for typical Gresham ADU projects.
Garage Conversion
$100,000 - $180,000Converting an existing garage is typically the most affordable path to an ADU. You save on foundation and framing since the basic structure exists. Costs vary based on garage condition, size, and finish level desired. Most garage conversions in Gresham result in studios or one-bedroom units between 400-600 square feet.
- Electrical and plumbing installation
- HVAC system
- Insulation and drywall
- Kitchen and bathroom
- Flooring and finishes
- Permits and inspections
Detached New Construction
$200,000 - $400,000Building a new detached ADU involves complete construction from the ground up. This option costs more but offers maximum design flexibility and typically commands higher rents. A one-bedroom detached ADU in Gresham typically costs $200,000-$280,000. Two-bedroom units range from $280,000-$400,000 depending on size and finishes.
- Foundation and site work
- Complete framing and roofing
- All mechanical systems
- Interior and exterior finishes
- Utility connections
- Design, engineering, permits
Attached Addition
$150,000 - $300,000Attached ADUs share a wall with your existing home, which can reduce some construction costs. You may be able to tie into existing roof structure and foundation, though this depends on your home's configuration. Costs fall between garage conversions and fully detached new construction for most Gresham projects.
- Foundation extension (if needed)
- Framing and roofing integration
- Separate entrance and utilities
- Complete interior buildout
- Fire separation requirements
- Permits and inspections
Return on Investment
Actual rents depend on unit size, finishes, location within Gresham, and current market conditions. One-bedroom ADUs typically rent higher than studios; two-bedroom units command premium rates.
According to Freddie Mac research, ADUs add 20-30% to property values in high-demand California markets. This often exceeds construction costs, creating immediate equity.
When you factor rental income against construction costs, many Gresham ADUs generate 8-12% annual cash-on-cash returns, competitive with or exceeding other investment options.
Frequently Asked Questions About ADUs in Gresham
Get answers to the most common questions about building an accessory dwelling unit in Gresham.
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