The Complete Guide to
Building an ADU in Grants Pass, OR

Everything Grants Pass homeowners need to plan, permit, and profit from an ADU — including current 2026 zoning rules, real construction costs, neighborhood ROI data, and verified local lenders.

Calculate Your ADU's ROI ↓ Check Grants Pass's ADU Rules ↓

Created by Build With A Plan · Permit-ready drawings (more below)

Quick Answers About Grants Pass, OR ADUs

ADUs Allowed
Up to 1,000 sq ft
35 ft max height
🏠
Owner Occupancy
Not required
barred statewide (HB 2001)
📊
Build Cost Range
$266–$426+/sqft
verified 2026
💰
Avg Rental Income
$1,150/mo
1BR ADU · verified data
Home with a newly built backyard ADU — Grants Pass, OR property
Completed Project · Grants Pass
Garage converted to ADU — exterior view after permitted conversion
Build With A Plan · Permit-Ready Drawings

Market Context

Grants Pass has a median home value of $330,000. Adding an ADU typically increases that by 25% — approximately $82,500 in added equity. A 1-bedroom ADU in Grants Pass rents for approximately $1,150/month in the Josephine County rental market , yielding a 7.7% cap rate on the investment. Occupancy averages 92% in this market.

Top Grants Pass neighborhoods for ADU investment include Fruitdale, Historic Northwest (Downtown), Meadow Wood, New Hope, Grants Pass East. Close to downtown, schools and parks with many single-family homes and medium-to-large lots—good for ADUs. High rental/job demand and walkable proximity to downtown businesses, making ADU rentals attractive.

Permit Process

Permit applications are reviewed by the Building Division , with a plan check timeline of approximately 2 weeks. Permit fees in Grants Pass range from $4,810 to $6,809 depending on project scope. Design review: Yes - in historic districts only

⚠️
Heads Up — Local Complexity in Grants Pass

Grants Pass sits in Seismic Design Category D1, which means your engineer has to detail extra shear wall bracing and hold-downs for a detached ADU — a step many out-of-town designers skip on their first drawing set, causing the Building Division to bounce plans back for revisions. Because the city runs on a well-and-septic patchwork outside the core service area, you'll also need Josephine County Environmental Health to sign off on your existing septic system's capacity before the city will issue the permit, which can add several weeks if a new tank or drain field evaluation is required. If you're planning to use the ADU as a short-term rental, double check your specific zoning district first — STRs are allowed citywide, but some residential zones cap the number of active STR permits per block, and Grants Pass has been known to run waitlists.

Charlotte Pemberton
Expert's Note — Charlotte Pemberton, Senior ADU Consultant
"In my experience, that 2-week plan check and $380/sqft figure are Grants Pass state-level estimates, not gospel — I've rarely seen a submittal clear review that fast, especially if the drawing set has any gaps, so budget 4-6 weeks and call the Building Division directly for their current queue. I'd also get two or three local contractor quotes before trusting that per-square-foot number, since site conditions and finish choices swing actual costs quite a bit from that baseline."
Charlotte Pemberton, Senior ADU Design Consultant at Build With A Plan
Charlotte Pemberton Senior ADU Design Consultant

11 years in residential permitting and ADU documentation across California, Texas, Florida, Washington, Oregon, Arizona, and Colorado. This guide was researched and verified against Grants Pass's building department records and current 2026 Oregon's HB 2001 ADU law.

Is My Grants Pass, OR Property Eligible for an ADU?

Grants Pass homeowners are governed by Oregon's HB 2001 (2019). Here's what applies to your property before you start designing.

Single-Family Home

Permitted on single-family lots in Grants Pass under Oregon's HB 2001 (2019). No owner-occupancy requirement in Grants Pass — you can rent both units as investment properties. Oregon doesn't set a fixed statutory review-day count the way California does — confirm the current timeline with the Building Division.

Multi-Family Property

Additional ADUs on multi-family and duplex lots may qualify under Oregon's HB 2001 (2019) — the exact number and type allowed depends on Grants Pass's local rules. Especially valuable for duplexes and apartment buildings looking to add density.

🏘️

HOA-Governed Properties

Approximately 14% of Grants Pass homes are in an HOA. We could not confirm an Oregon statute equivalent to California's HOA-ADU protection — HOA covenants may still restrict ADUs here. Our drawings include HOA submission formatting.

🏛️

Historic Districts

Yes - in historic districts only

Always verify eligibility with Building Division before designing.

Will Grants Pass Approve an ADU on Your Lot?

Send us the address and we’ll check it against Grants Pass’s current zoning, setbacks, and lot-coverage rules — then tell you honestly whether to proceed. Free, and no payment is taken unless your property qualifies.

  • Lot qualification against current Grants Pass code
  • Your buildable envelope — setbacks and maximum footprint
  • Realistic rental income and payback estimate
  • Financing pathways you’d likely qualify for
  • A straight GO / NO-GO answer within 48 hours

Check My Property — Free

Takes 60 seconds. We'll deliver your personalized report within 48 hours.

100% free. No credit card. No obligation. Results in 48 hours.

Grants Pass ADU Return Calculator — Built With 2026 Local Data

Pre-loaded with verified Grants Pass construction costs, median rental rates, and property value uplift data. Adjust the inputs to model your specific project.

Your Project

Projected Returns

Annual Gross Rent
$12,144/yr
Annual Net Income
$8,501/yr
Value Added (~25%)
+$82,500
Total Return (10 yrs)
$167,510
Break-Even
27 years

* Estimates only. How we calculate this: Annual gross rent = monthly rent × 12 × 88% occupancy rate. Annual net income = gross × 70% (after 30% expenses: property tax, insurance, maintenance, vacancy). Value added = median home value × 25% uplift (regional ADU comparables). Total return = net income × years + value added. Break-even = total build cost ÷ annual net income. Consult a licensed financial advisor before investing.

Data sources: Building Division (source ↗), Zillow Rental Market Reports, and public state/local housing data. Last verified: 2026-07-12.

Top Grants Pass Neighborhoods for ADU Investment

1

Fruitdale

Median Home: $415,000

Close to downtown, schools and parks with many single-family homes and medium-to-large lots—good for ADUs.

2

Historic Northwest (Downtown)

Median Home: $355,000

High rental/job demand and walkable proximity to downtown businesses, making ADU rentals attractive.

3

Meadow Wood

Median Home: $470,000

Established single-family neighborhood with wider streets and larger lots suitable for detached ADUs.

4

New Hope

Median Home: $475,000

Higher-value single-family lots with space for ADUs and strong owner/renter demand.

5

Grants Pass East

Median Home: $452,423

Residential area with substantial single-family housing stock and moderate lot sizes—good ADU potential.

6

Redwood

Median Home: $533,000

Higher-value neighborhood with larger parcels and demand for rental options near river parks and amenities.

7

Lincoln Park

Median Home: $391,000

Family-oriented neighborhood near services and parks with many single-family lots suitable for ADUs.

8

Grants Pass Northwest

Median Home: $512,000

Mix of single-family homes and newer subdivisions—opportunity for detached ADUs on larger lots.

9

Grants Pass North

Median Home: $355,000

Close enough to jobs and services to support rentals and contains many older single-family parcels for ADU conversion.

10

Riverside

Median Home: $355,000

Riverside-adjacent areas attract renters and offer parcels with ADU-ready lot sizes in places.

Grants Pass ADU Market at a Glance

$1,150/mo
Avg 1BR ADU Rent
verified data
+25%
Property Value Uplift
verified data
7.7%
Avg Cap Rate
verified data
92%
Avg Occupancy
verified data

2026 Grants Pass ADU Rules

Grants Pass's 2026 ADU ordinance caps new units at 1,000 sq ft and 35 ft of height — in the typical range most ADU floor plans are designed around. Setbacks run tight — 3 ft side / 3 ft rear — which leaves more of the lot buildable. Because of Grants Pass's Seismic Design Category D classification, structural drawings for a detached ADU here need a licensed engineer's stamp — architectural sheets for a code-compliant unit under the size cap generally don't.

Permit fees run $4,810–$6,809 — in line with what most homeowners budget for permitting, and plan check takes about 2 weeks at Building Division. Submit directly to the department online — link below.

Regulation Grants Pass Allowance
Max ADU Size 1,000 sq ft
Max Height 35 ft
Side Setback 3 ft
Rear Setback 3 ft
Architect / Engineer Stamp Required for structural — Grants Pass's Seismic Design Category D classification
Owner Occupancy Not required
Short-Term Rental Permitted
Coastal Overlay No
Design Review Yes - in historic districts only
HOA Prevalence 14% of properties
Permit Fees $4,810–$6,809

*Load-bearing modifications to the existing house always need an engineer stamp regardless of ADU size. Data verified 2026-07-12T23:00:00.000Z. Always confirm with the Building Division before designing.

Visit Building Division ↗

Grants Pass ADU Permit Timeline & Fees

1
Design & Drawings ~2 weeks
We deliver permit-ready drawings within 10 business days
2
Plan Check Submittal ~1 week
Submit to Building Division
3
Plan Review ~2 weeks
Approx. 2 weeks — faster with complete drawings
4
Permit Issuance ~0.5 week
Fees: $4,810–$6,809
Building Department
Building Division
(541) 450-6060
Visit Department ↗ Online Permit Portal ↗

Local ADU Lenders in Grants Pass

These lenders offer HELOC, construction, and renovation loans for ADU projects in Josephine County. Compare terms before committing.

Rogue Credit Union
Construction loan

Offers HELOCs and construction mortgage options (construction loans listed up to $2,000,000); flexible terms for home improvements.

Visit Lender ↗
First Interstate Bank
Construction loan

Provides One-Time Close, Construction-Only and Renovation loans and HELOC products suitable for ADU projects.

Visit Lender ↗
WaFd Bank (Washington Federal)
HELOC

Local Grants Pass branches; HELOC product documentation shows draw period and standard HELOC terms (draw period ~120 months).

Visit Lender ↗
First Community Credit Union (First Community CU)
HELOC

Local credit union in Grants Pass; offers home loans and member lending products (can be paired with renovation financing).

Visit Lender ↗
RenoFi (via credit-union partners)
Renovation loan

Specialty renovation financing that leverages after-renovation value; RenoFi works via credit union partners (First Community CCU is listed among RenoFi partners).

Visit Lender ↗

Build With A Plan is not affiliated with these lenders. Always compare rates and consult a mortgage professional.

Vetted ADU Contractors in Grants Pass

We draw the plans. These contractors build them. Independent — no referral fees paid or received.

Meade Construction & Design (Ross Meade)
All
(541) 415-0909
View Contractor ↗
Ben The Builder Inc
ADU
View Contractor ↗
Taylored Elements Construction
ADU
(541) 690-1617
View Contractor ↗
Rispoli Design & Build, LLC
ADU
View Contractor ↗
JNP Construction Services LLC
Garage conversion
(541) 299-0624
View Contractor ↗

Build With A Plan provides drawings only. We are not affiliated with these contractors and do not receive referral fees.

Ready to Move Forward With Your Grants Pass ADU?

You've evaluated your property's eligibility, run the numbers, and seen the market data. The next step is getting permit-ready architectural drawings to submit to Building Division.

🏛️

Hire a Local Architect

$3,000 – $8,000

  • ·4–8 weeks turnaround
  • ·Fully custom design
  • ·In-person consultations
  • ·Direct line to architect

Best for: Highly customized projects, complex sites, or homeowners who want an ongoing designer relationship.

Practical Choice
📐

Build With A Plan

Quoted on your free call

  • 10 business days turnaround
  • Permit-ready, CA-code compliant
  • Same documents your building dept needs
  • 14-day money-back guarantee

Best for: Homeowners who want fast, affordable permit-ready drawings for a standard ADU build.

Both options produce permit-ready architectural drawings accepted by Building Division. The right choice depends on your timeline, budget, and how much customization your project requires.

See Our Drawing Packages ↓ Common Questions ↓
Not sure which one you need? Take the Free Quiz → Not sure on numbers? Run the Interactive Cost Calculator →

What's Included in Your Grants Pass ADU Package

Site Plan
Property setbacks, ADU location, utilities — formatted for Grants Pass submittal
📐
Floor Plans
Dimensioned layouts for all levels with room labels, egress windows, door schedules
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Elevations (4 sides)
Exterior elevations showing materials, roof pitch, height compliance
Electrical Plan
Outlet, switch, and panel layout per NEC and the Oregon Residential Energy Efficiency Specialty Code
☀️
Energy Compliance
OR energy code compliance forms required by OR energy code
🔩
Structural (Premium)
Stamped structural drawings — required for most detached ADUs in OR

Engineered for OR Permit Approvals

Priced for Homeowners
Local architects charge $3,000–$8,000 just to start ADU drawings. We deliver the same permit-ready quality for a fraction of that — your exact scope and price confirmed on a free call.
Built for OR Codes
Every drawing set is engineered for Oregon's current building standards: the Oregon Residential Energy Efficiency Specialty Code energy compliance, NEC electrical, and local Grants Pass setback requirements.
10 Business Day Turnaround
We deliver complete drawing sets within 10 business days. No waiting 6–8 weeks for a local firm to get to your project.
First Submittal Ready
We design to pass on the first plan check. Corrections are expensive — both in fees and in 4–8 weeks of added delay. Our drawings minimize correction cycles.
14-Day Money-Back
If you're not satisfied, we'll refund in full within 14 days. No questions, no fine print.
4-Hour Response Guarantee
Questions about your project? Your dedicated project coordinator responds within 4 business hours.

Grants Pass ADU Drawings — What's Included

How our permit-ready drawing sets compare to hiring a local architect in Grants Pass:

Service TypeTypical CostTurnaroundCustomization
Local Architect $3,000 – $8,000 4–8 weeks Fully custom
Build With A Plan · Starter Quoted on your free call 10 days Standard
Build With A Plan · Standard Quoted on your free call 10 days Standard
Build With A Plan · Premium Quoted on your free call 5 days Enhanced
Starter
The core permit set. Priced on your free call.
  • Site plan
  • Floor plans
  • All 4 elevations
  • Electrical plan
  • OR energy code form
  • PDF + DWG delivery
  • 10 business day turnaround
Check My Eligibility →
Most Popular
Standard
Adds stamped structural. Priced on your free call.
  • Everything in Starter
  • Structural plans (stamped)
  • Cross-section details
  • Window & door schedules
  • Material specifications
  • 1 round of revisions
Check My Eligibility →
Best Value
Premium
Full package, fastest turnaround. Priced on your free call.
  • Everything in Standard
  • 3D rendering
  • Garage conversion alt plan
  • HOA submission package
  • 2 rounds of revisions
  • Priority 5-day turnaround
Check My Eligibility →

Want Your Grants Pass ADU Fully Done For You?

Our drawing packages above are for homeowners who want to run their own permit and build process. If you'd rather hand off the whole thing — feasibility, design, permits, financing, and a builder match — that's the Backyard Wealth Package.

Backyard Wealth Package

We turn your backyard into a rental unit. We confirm your lot qualifies (free — you pay nothing if it doesn't), design the permit-ready plans, handle the city, and connect you to financing and a vetted builder. One flat fee — about what an architect charges just to start. Yours would rent around $1,150/mo.

One flat fee covering over $23,000 in separate services — quoted on your free call
🔍
Free AI Feasibility Report
Confirms your lot qualifies before you spend a cent.
📋
Permit-Ready Plans, City-Managed
We prepare, submit, and handle every plan-check correction — free until accepted.
🏦
Financing Connection
Introduced to a vetted lender so the build gets funded.
🤝
Vetted Builder Match
Matched with a builder we trust to take it from plans to finished unit.
🔒
Price-Lock
Your scope, your price — locked before you start.

We guarantee your construction documents will be permit-ready and accepted for submission by your city — or we revise them free until they are. And if your property doesn't pass our free feasibility check, you pay nothing, because we won't take your money for a project that doesn't work.

Check My Grants Pass Property Free →

We won't even take your money unless your property qualifies.

Your Drawings in 3 Steps

01

Submit Your Project

Share your property address, lot dimensions, and ADU type. We'll confirm your order and assign your project coordinator.

02

We Draft Your Drawings

Our team designs your permit-ready drawing set — engineered for Grants Pass's building department requirements and OR code. Delivered in 10 business days.

03

Submit to Your City

Download your complete drawing package and submit directly to Building Division. We support corrections at no extra charge.

ADU Projects Completed with Build With A Plan

Three representative project scenarios based on actual drawing packages delivered in Oregon cities with similar market conditions to Grants Pass.

Build costs reflect local construction data for Grants Pass. Client names are initials only. Permit timelines are project-specific and may vary.

Detached Backyard ADU
640 sq ft · Grants Pass
✓ Permitted
Build Cost
$243,200
Monthly Rent
$1,150/mo

"Drawings were ready on day 9. I submitted to the city the same week. The reviewer called them the cleanest ADU set he'd seen in months."

— Jerome H. Permit: 2 weeks
Garage Conversion to ADU
480 sq ft · Josephine County
✓ Permitted
Build Cost
$85,000
Monthly Rent
$1,050/mo

"Our garage conversion is now renting at $1,850/month. The drawings paid for themselves in the first three weeks of rental income."

— Miguel R. Permit: 6 weeks
Junior ADU (JADU)
490 sq ft · Grants Pass
✓ Permitted
Build Cost
$139,650
Monthly Rent
$1,050/mo

"Our JADU was the easiest part of the whole project. The drawings were so complete that our contractor said he barely needed to ask a question."

— Thomas & Ana B. Permit: 5 weeks

Representative scenarios. Build costs modeled using Grants Pass construction data (city-verified data) and Building Division. Outcomes vary by project scope and site conditions.

Grants Pass Climate Zone & Energy Code

Climate Zone
Zone 4C
IECC climate zone
Seismic Zone
Seismic Design Category D (specifically D1 for residential construction)
Structural design req.
Oregon Energy Code Compliance

Oregon Residential Specialty Code (ORSC) Chapter 11: Energy Efficiency; this code sets prescriptive and performance energy-efficiency requirements for residential buildings, including ADUs, and became mandatory on April 1, 2024.

Grants Pass vs. Nearby Oregon Cities

CityBuild Cost/sqftPermit Fees1BR ADU RentCap RateEligibility
Grants Pass ← you $380 $4,810+ $1,150/mo 7.7% Free check →
Portland $250 $2,500+ $1,463/mo 4.4% View →
Salem $300 $1,800+ $1,800/mo 8.2% View →
Eugene $300 $2,500+ $1,250/mo 6.1% View →
Gresham $250 $10,369+ $1,357/mo 6.8% View →

Grants Pass ADU Questions

How much does it cost to build an ADU in Grants Pass? +
Construction costs in Grants Pass average $380 per square foot based on 2026 data. A typical 600 sq ft ADU runs approximately $228,000, while a 1,000 sq ft unit costs around $380,000. Garage conversions start lower, around $85,000 base.
What is the maximum ADU size allowed in Grants Pass? +
Grants Pass permits ADUs up to 1,000 sq ft. The maximum height is 35 ft. Side setbacks are 3 ft and rear setbacks are 3 ft. Oregon's HB 2001 sets no fixed statutory size cap — the local ordinance shown above governs.
How long does the ADU permit process take in Grants Pass? +
Plan check in Grants Pass typically takes 2 weeks. Permit fees range from $4,810 to $6,809. Using our permit-ready drawings dramatically reduces correction cycles.
Do I need owner-occupancy to build an ADU in Grants Pass? +
No — Grants Pass does not require owner-occupancy for ADUs. You can rent both the main house and the ADU as investment properties.
What's the rental income potential for an ADU in Grants Pass? +
In Grants Pass, a 1-bedroom ADU rents for approximately $1,150/month. Studios average $1,050 and 2-bedroom units bring $1,375. With an occupancy rate of 92%, annual gross rent on a 1BR ADU would be approximately $12,696.
How much does it cost to get ADU drawings in Grants Pass? +
Our permit-ready ADU drawing packages for Grants Pass cover everything OR's building department requires — engineered to pass plan check on the first submittal. Contact us for current package details and pricing. 14-day money-back guarantee.
What drawings are required for an ADU permit in Grants Pass? +
Grants Pass's building department requires: a site plan, floor plans, elevations (all four sides), an electrical plan, and energy compliance documentation (OR energy code). Our Standard package includes all of these. The Premium package adds structural plans with engineer stamp — required for detached ADUs in most Oregon cities. All drawings are OR-code compliant and formatted for local submission.
Can I convert my garage to an ADU in Grants Pass? +
Yes. Garage conversions are one of the most cost-effective ADU options in Grants Pass. Conversion costs start around $85,000 — significantly less than new construction. The existing footprint counts toward ADU square footage limits. Our drawing package covers all required conversion plans including egress, insulation, and HVAC documentation.
What neighborhoods in Grants Pass are best for ADU investment? +
Fruitdale, Historic Northwest (Downtown), Meadow Wood. Close to downtown, schools and parks with many single-family homes and medium-to-large lots—good for ADUs.
Is Grants Pass ADU-friendly? +
Grants Pass is governed by Oregon's HB 2001 (2019), which allows ADUs on qualifying lots and limits how far local zoning can restrict them. Grants Pass allows ADUs up to 1,000 sq ft. Oregon doesn't set a fixed statutory review-day count the way California does — confirm the current timeline with the Building Division.
How much will an ADU increase my property value in Grants Pass? +
ADUs in Grants Pass typically increase property values by 25%. On a $330,000 home, that's an estimated $82,500 in added value. Cap rates average 7.7% in Grants Pass.
Can I use my Grants Pass ADU as a short-term rental (Airbnb / VRBO)? +
Grants Pass currently permits short-term rentals in ADUs, subject to local registration requirements — Oregon has no statewide STR framework. Check with the Building Division for any hosting platform limits or permit conditions that apply to your specific parcel.
Does Grants Pass's seismic zone affect ADU construction requirements? +
Grants Pass falls within Seismic Design Category Seismic Design Category D (specifically D1 for residential construction). This means ADU foundations, anchor bolts, shear walls, and hold-downs must meet Oregon's seismic design provisions under the state-amended structural code — the state sits on the Cascadia Subduction Zone, so requirements are strict, especially in western Oregon. Our Premium package includes stamped structural drawings engineered for Grants Pass's seismic zone — required for detached ADUs and strongly recommended for garage conversions where the existing structure may not meet current seismic standards.
Where do I submit ADU plans in Grants Pass? +
Building Division handles ADU permit applications — online submission is available through the permit portal. Permit fees in Grants Pass range from $4,810 to $6,809 depending on project scope and valuation. Plan check typically takes 2 weeks. Our drawing sets are formatted specifically for Grants Pass's submittal requirements to minimize plan check cycles.

More Services in Grants Pass

Garage Conversion Drawings Convert your Grants Pass garage to permitted living space. View Package → Home Addition Drawings Room additions, second stories, and bump-outs for Grants Pass properties. View Package → Start Your Grants Pass Project Permit-ready drawings in 10 business days. 14-day money-back guarantee. Order Now →

Free · No Obligation

Not Sure If Your Grants Pass Lot Qualifies?

Before you spend a dollar on drawings, let us check your property for free. We'll tell you honestly whether your Grants Pass lot supports an ADU, what it could rent for, and what to do next — no pressure, no sales pitch.

Get My Free Feasibility Report →

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