What is an ADU?
ADU is short for Accessory Dwelling Unit. It can be accessory to detached single-family homes, townhouses, manufactured homes and duplex dwellings on their own lot.
Jump to your town’s ADU rules: Medford – Phoenix – Talent – Ashland – Central Point – Jackson County
If you are a professional homebuilder, see this set of ideas.
Why ADUs are important for you and your community
- Creates more housing density at lower costs within the Urban Growth Boundaries that maintain our wide open spaces for ag and wildlife.
- Serves people and places according to AARP by creating attainable housing for elders and people starting out.
- Supports aging in place, generational wealth building, and housing for extended family or friends.
- Adds affordable “missing middle” housing options in a moment of critical shortage/ opportunity. Missing middle is everything from ADUs to 8 unit complexes.
- Generates income – what does a 1 bedroom unit rent for in your area?
- Increases property values 25% to 34%. A 2012 study from Portland.
- Accelerates mortgage payoff at a time when 24% of Oregon homeowners are mortgage burdened and of that 9% are severely cost burdened- Oregon Center for Public Policy
- Reduces the need for cars and increases walking, biking, and transit use.
How an ADU could work for you
- ADUs are extremely valuable when it’s time to sell your home.
- Studies show that ADUs can increase property values and make homes more desirable to potential buyers, especially those interested in aging-in-place.
- Estimate your gains using this handy calculator. Scroll down the calculator to adjust assumptions. Or try this calculator.
Here’s Derek Sherrell, local ADU developer who offers a lot of great advice and encouragement to anyone interested in ADUs.
See more tips from Derek, That ADU Guy, on YouTube and on his website.
Pre-approved ADU Plans
Here’s Carlos Delgado, the architect who designed the ADU plans pre approved in the city of Medford talking about his approach to ADUs.
When ADUs might not work
- Zoning restrictions – most single family lots can now include an ADU
- Not enough space on your lot – buildable area of your lot, set backs, etc.
- Access to utilities is expensive – is there enough slope for the sewer line?
- Upfront costs of planning and permits
- Financing ADU’s can be tricky – check with your banker
- The form of your existing house may not make an attached ADU easy – attached ADU example
Check with your local community development staff before you give up on the ADU idea. More info below
How to get started
Here’s Kristen Maze, Director of Community Development at the City of Talent helping you think about preparing to apply for permits to build an ADU.
Trying to Make the Complex Simpler
This process is NOT simple. We are trying to help you get started, but know that there are many options and potential roadblocks along the way. But, as Derek says, the hard work is definitely worth it!
Lots of good materials on these websites:
- Building an ADU – resource book, podcast, etc.
- Here is a cost calculator for ADUs based on some simple assumptions.
- That ADU Guy
- The city of Houston, TX has great ADU resources including a free ebook of plans.
A Few Key Details About ADUs In Your Area
This is only a few key pieces of a much larger puzzle. Check with your local planning department, their contact information is at the top of this table. On your phone, click on the phone number to dial it.
Click to jump to your town: Medford – Phoenix – Talent – Central Point – Jackson County
Ashland
Planning department contact information
ADUs are allowed in zones
R-1, R-1-3.5, RR, WR, R-2, R-3, NN, NM
Setbacks and coverage ratios
Set back and coverage ratios vary for different zones. Find the requirements for your zone here.
Other rules
Just a start here, look at more info links for the complete picture
Off-street parking is NOT required
Accessory Residential Units (ARU) and in the Single-Family Residential Zones (R-1-5/R-1-7.5 & R-1-10) ARUs require a Conditional Use Permit.
More info here
Link to building permits
Permits, Forms, & Fees
Central Point
Planning department contact information
541-664-3321
stephanie.holtey@centralpointoregon.gov
ADUs are allowed in zones
R-L, R-1, R-2
LMR, MMR, HM
Setbacks and coverage ratios
Rear Yard Setback: 5 ft
800 sq ft or 50% of the gross floor area of the primary dwelling, whichever is less
Other rules
– just a start here, look at more info links for the complete picture
Off street parking is NOT required.
Separate utility connections are not required
More info here
Link to building permits
Permits
Medford
Planning department contact information
541-774-2380
planning@cityofmedford.org
ADUs are allowed in zones
MFR-30, MFR-20, MFR-15, SFR-10, SFR-6, SFR-4, SFR-2
Setbacks and coverage ratios
Up to 75% of the primary dwelling’s Gross Habitable Floor Area (GHFA)
Detached ADUs cannot be larger than 900 sq. ft.; attached ADUs converted from existing space in the primary home cannot be larger than 50% of the primary dwelling
Other rules
– just a start here, look at more info links for the complete picture
Off street parking is NOT required
More Info here
Link to building permits
Applying for a permit
ADU Fee Waiver
Phoenix
Planning department contact information
ADUs are allowed in zones
R-1
Setbacks and coverage ratios
Maximum lot coverage 40%
Minimum lot size 6,000sqft
Other rules
– just a start here, look at more info links for the complete picture
Off street parking is NOT required
More info here
Link to building permits
Building permit information here
Talent
Planning department contact information
ADUs are allowed in zones
RLD, RMD, RHD, RMH, CN
Setbacks and coverage ratios
Not to exceed 800 square feet of floor area, or 75 percent of the primary dwelling’s floor area, whichever is smaller.
Other rules
– just a start here, look at more info links for the complete picture
Off street parking is NOT required
More info here
Link to building permits
Jackson County
Planning department contact information
ADUs are allowed in zones
Unlikely outside the UGB, White City allows ADUs.
Rural areas are unlikely to allow ADUs. That is under review in the state wildfire risk map that is to be completed in Fall 2022.
Depends on your zoning because the County considers an ADU a separate dwelling on the lot.
Setbacks and coverage ratios
Depends on your zoning.
Other rules
Consult with planners at the County.
Link to building permits
How to finance your ADU construction
- Local banks you currently work with – equity line of credit, cash out refinance, etc.
- Craft3 ADU finance program
- In Portland, some developers who lease your land and build an ADU for you
- There is a lot of useful data around cost assumptions and financing options in this document from Santa Cruz County in California. Of course, our fees are different, but many of the construction cost estimates, financing options, etc. are still useful.
Oregon State ADU Code
Oregon Statue on Accessory Dwelling Units in Rural Residential Areas
ADUs are an important way to fill in the missing middle in our housing supply.
What Home Builders Can Do to Simplify Later ADU Development
Professional home builders can make ADU development much easier by planning ahead. This video offers a few good ideas.
One creative idea for affordable homes with ADUs is for builders to build the ADU first and sell the large lot with its approved larger home site left for future development. This allows buyers to get started on homeownership more easily while they can look forward to building their larger home once they have built equity in their starter home.
