The Complete Guide to
Building an ADU in The Dalles, OR

Everything The Dalles 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 The Dalles's ADU Rules ↓

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

Quick Answers About The Dalles, OR ADUs

ADUs Allowed
Up to 800 sq ft
18 ft max height
🏠
Owner Occupancy
Not required
barred statewide (HB 2001)
📊
Build Cost Range
$267–$400+/sqft
verified 2026
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Avg Rental Income
$505/mo
1BR ADU · verified data
Home with a newly built backyard ADU — The Dalles, OR property
Completed Project · The Dalles
Garage converted to ADU — exterior view after permitted conversion
Build With A Plan · Permit-Ready Drawings

Market Context

The Dalles has a median home value of $380,000. Adding an ADU typically increases that by 25% — approximately $95,000 in added equity. A 1-bedroom ADU in The Dalles rents for approximately $505/month in the Wasco County rental market , yielding a 6.9% cap rate on the investment. Occupancy averages 87% in this market.

Top The Dalles neighborhoods for ADU investment include East Corridor (Hospital & College), Riverview, Downtown & Historic Core, Old Dufur / Richmond, East The Dalles. Anchored by Adventist Health Columbia Gorge and Columbia Gorge Community College, this corridor has steady year-round rental demand from healthcare workers, students, and faculty on modest SFH lots ideal for ADUs. Quiet, walkable, river-adjacent neighborhood with strong sense of community and established single-family homes within commuting distance of downtown employers and the hospital.

Permit Process

Permit applications are reviewed by the Building Codes Services . Permit fees in The Dalles range from $3,000 to $4,500 depending on project scope. Design review: Yes - in historic districts only

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Heads Up — Local Complexity in The Dalles

Because Wasco County contracts building permits through Building Codes Services rather than a city-run office, homeowners often assume they can walk plans into City Hall — but you actually need to route through the county's process, which uses the 2026 fee schedule plus a new 3% tech surcharge added in August 2025. Many older lots in The Dalles were platted before modern water/sewer separation rules, so expect the county to require a site inspection confirming your ADU's sewer lateral doesn't cross under the existing house's foundation, a fix that can mean trenching through a finished basement. Since STRs are allowed here, plan ahead if you want to rent the ADU nightly — you'll still need to clear a separate STR registration with the county after your final building inspection, and that approval can lag weeks behind your certificate of occupancy.

Charlotte Pemberton
Expert's Note — Charlotte Pemberton, Senior ADU Consultant
"In my experience, the missing timeline and cost-per-square-foot figures here are a red flag rather than good news — these are likely unverified state-level placeholders, and I'd strongly advise calling Wasco County Building Codes Services directly and getting a couple of local contractor bids before you budget anything. What the data doesn't show is that even straightforward ADU submittals in The Dalles can see plan check stretch well past 8 weeks if the drawing set isn't complete on first pass."
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 The Dalles's building department records and current 2026 Oregon's HB 2001 ADU law.

Is My The Dalles, OR Property Eligible for an ADU?

The Dalles 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 The Dalles under Oregon's HB 2001 (2019). No owner-occupancy requirement in The Dalles — 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 Codes Services.

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 The Dalles's local rules. Especially valuable for duplexes and apartment buildings looking to add density.

🏘️

HOA-Governed Properties

Approximately 16% of The Dalles 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 Codes Services before designing.

Will The Dalles Approve an ADU on Your Lot?

Send us the address and we’ll check it against The Dalles’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 The Dalles 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.

The Dalles ADU Return Calculator — Built With 2026 Local Data

Pre-loaded with verified The Dalles 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
$5,333/yr
Annual Net Income
$3,733/yr
Value Added (~25%)
+$95,000
Total Return (10 yrs)
$132,330
Break-Even
49 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 Codes Services (source ↗), Zillow Rental Market Reports, and public state/local housing data. Last verified: 2026-08-15.

Top The Dalles Neighborhoods for ADU Investment

1

East Corridor (Hospital & College)

Median Home: $360,000

Anchored by Adventist Health Columbia Gorge and Columbia Gorge Community College, this corridor has steady year-round rental demand from healthcare workers, students, and faculty on modest SFH lots ideal for ADUs.

2

Riverview

Median Home: $395,000

Quiet, walkable, river-adjacent neighborhood with strong sense of community and established single-family homes within commuting distance of downtown employers and the hospital.

3

Downtown & Historic Core

Median Home: $425,000

Walkable historic core near downtown jobs, cafes and civic institutions; qualifies for up to $10,000 in urban renewal funding that helps offset ADU development costs.

4

Old Dufur / Richmond

Median Home: $410,000

Mature rural-charm area with river views and larger legacy parcels that easily accommodate detached ADUs while appealing to long-term renters.

5

East The Dalles

Median Home: $345,000

Peaceful, family-friendly neighborhood with abundant single-family homes and affordable prices that produce strong rental yields on new ADUs.

6

Sorosis Park

Median Home: $380,000

Family-friendly pocket bordering Sorosis Park, the high school and the hospital corridor, giving tenants quick access to schools, recreation and jobs.

7

Westside / Chenoweth

Median Home: $355,000

Car-oriented area with Highway 30 and I-84 access, ranging from starter homes to newer subdivisions that offer many detached-ADU candidates.

8

Chenowith Creek

Median Home: $370,000

Scenic, privacy-rich single-family neighborhood with larger lots along the creek that comfortably fit detached ADUs.

9

Lone Pine / Columbia River Shore

Median Home: $475,000

Exclusive river-shore community where the larger 0.27+ acre parcels command premium ADU rental rates from Gorge-commuting professionals.

10

Summit Ridge Drive

Median Home: $365,000

Peaceful hillside family neighborhood with newer single-family construction and proximity to Mt. Hood and Union corridors that attract long-term renters.

The Dalles ADU Market at a Glance

$505/mo
Avg 1BR ADU Rent
verified data
+25%
Property Value Uplift
verified data
6.9%
Avg Cap Rate
verified data
87%
Avg Occupancy
verified data

2026 The Dalles ADU Rules

The Dalles's 2026 ADU ordinance caps new units at 800 sq ft and 18 ft of height — on the tighter side, which narrows floor plan options. Setbacks run 3 ft side and 5 ft rear, close to the regional baseline. The Dalles doesn't trigger the extra engineer-stamp requirement we see in higher seismic-risk or hurricane-code cities — a standard code-compliant ADU under the size cap can typically be designed and submitted without an architect or engineer stamp, though any load-bearing change to the existing house still needs one.

Permit fees run $3,000–$4,500 — in line with what most homeowners budget for permitting through Building Codes Services. Submit directly to the department online — link below.

Regulation The Dalles Allowance
Max ADU Size 800 sq ft
Max Height 18 ft
Side Setback 3 ft
Rear Setback 5 ft
Architect / Engineer Stamp Not required under the size cap*
Owner Occupancy Not required
Short-Term Rental Permitted
Coastal Overlay No
Design Review Yes - in historic districts only
HOA Prevalence 16% of properties
Permit Fees $3,000–$4,500

*Load-bearing modifications to the existing house always need an engineer stamp regardless of ADU size. Data verified 2026-08-15T06:10:50.038Z. Always confirm with the Building Codes Services before designing.

Visit Building Codes Services ↗

The Dalles 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 Codes Services
3
Plan Review ~8 weeks
Approx. 8 weeks — faster with complete drawings
4
Permit Issuance ~0.5 week
Fees: $3,000–$4,500
Building Department
Building Codes Services
(541) 506-2650
Visit Department ↗ Online Permit Portal ↗

Local ADU Lenders in The Dalles

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

Rivermark Community Credit Union
HELOC

Local credit union with a The Dalles branch; HELOC as low as 6.99% APR with a 10-year draw / 20-year repayment period, minimum $5,000, usable for home improvements and renovations including ADUs.

Visit Lender ↗
First Interstate Bank
Construction loan

Regional bank with a The Dalles branch at 1100 W. Sixth St; offers One-Time Close construction-to-permanent, Construction-Only, and Renovation loans, plus a HELOC currently at 5.24% intro APR for 6 months.

Visit Lender ↗
Guild Mortgage
Construction loan

Has a The Dalles branch at 306 Court St., Suite B; offers new construction loans, renovation loans, HELOC, and cash-out refinance — all usable for ADU construction.

Visit Lender ↗
Craft3
Renovation loan

Pacific Northwest CDFI offering dedicated ADU Loans up to $150,000 for design, permitting, and construction; fixed rates with income-qualified reductions; serves all of Oregon including rural areas like The Dalles.

Visit Lender ↗
OnPoint Community Credit Union
HELOC

Large Oregon/Washington credit union offering the EquityFlex HELOC and a Fixed Portion option usable for home improvements, renovations, and ADU construction; broadly accessible across Oregon.

Visit Lender ↗

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

Vetted ADU Contractors in The Dalles

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

Ellett Construction
ADU
(XXX) XXX-XXXX
View Contractor ↗
Crestline Construction
All
(XXX) XXX-XXXX
View Contractor ↗
Green Gorge Construction
All
(XXX) XXX-XXXX
Gorge Dream Builders
Home addition
(XXX) XXX-XXXX
Krieg Construction Company, LLC
All
(XXX) XXX-XXXX

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 The Dalles 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 Codes Services.

🏛️

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 Codes Services. 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 The Dalles ADU Package

Site Plan
Property setbacks, ADU location, utilities — formatted for The Dalles 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 The Dalles 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.

The Dalles ADU Drawings — What's Included

How our permit-ready drawing sets compare to hiring a local architect in The Dalles:

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 The Dalles 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 $505/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 The Dalles 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 The Dalles'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 Codes Services. 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 The Dalles.

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

Detached Backyard ADU
640 sq ft · The Dalles
✓ Permitted
Build Cost
$192,000
Monthly Rent
$505/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: 8 weeks
Garage Conversion to ADU
480 sq ft · Wasco County
✓ Permitted
Build Cost
$115,000
Monthly Rent
$1,166/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 · The Dalles
✓ Permitted
Build Cost
$102,900
Monthly Rent
$1,166/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 The Dalles construction data (city-verified data) and Building Codes Services. Outcomes vary by project scope and site conditions.

The Dalles Climate Zone & Energy Code

Climate Zone
Zone 5B
IECC climate zone
Seismic Zone
C
Structural design req.
Oregon Energy Code Compliance

Oregon (non-California) uses the 2023 Oregon Residential Specialty Code (ORSC), with Chapter 11 containing the residential building energy provisions (mandatory statewide as of April 1, 2024); Oregon also offers an optional 'Oregon Residential Reach Code' (Passivhaus-level) as an above-code path.

The Dalles vs. Nearby Oregon Cities

CityBuild Cost/sqftPermit Fees1BR ADU RentCap RateEligibility
The Dalles ← you $3,000+ $505/mo 6.9% 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 →

The Dalles ADU Questions

How much does it cost to build an ADU in The Dalles? +
Construction costs in The Dalles typically range from $200–$400 per square foot depending on project complexity, finishes, and site conditions.
What is the maximum ADU size allowed in The Dalles? +
The Dalles permits ADUs up to 800 sq ft. The maximum height is 18 ft. Side setbacks are 3 ft and rear setbacks are 5 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 The Dalles? +
Oregon's HB 2001 sets no fixed statewide day-count for ADU review — plan check commonly runs 4–10 weeks depending on the jurisdiction.
Do I need owner-occupancy to build an ADU in The Dalles? +
No — The Dalles 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 The Dalles? +
In The Dalles, a 1-bedroom ADU rents for approximately $505/month. Studios average $1,166 and 2-bedroom units bring $1,397. With an occupancy rate of 87%, annual gross rent on a 1BR ADU would be approximately $5,272.
How much does it cost to get ADU drawings in The Dalles? +
Our permit-ready ADU drawing packages for The Dalles 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 The Dalles? +
The Dalles'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 The Dalles? +
Yes. Garage conversions are one of the most cost-effective ADU options in The Dalles. Conversion costs start around $115,000 — 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 The Dalles are best for ADU investment? +
East Corridor (Hospital & College), Riverview, Downtown & Historic Core. Anchored by Adventist Health Columbia Gorge and Columbia Gorge Community College, this corridor has steady year-round rental demand from healthcare workers, students, and faculty on modest SFH lots ideal for ADUs.
Is The Dalles ADU-friendly? +
The Dalles is governed by Oregon's HB 2001 (2019), which allows ADUs on qualifying lots and limits how far local zoning can restrict them. The Dalles allows ADUs up to 800 sq ft. Oregon doesn't set a fixed statutory review-day count the way California does — confirm the current timeline with the Building Codes Services.
How much will an ADU increase my property value in The Dalles? +
ADUs in The Dalles typically increase property values by 25%. On a $380,000 home, that's an estimated $95,000 in added value. Cap rates average 6.9% in The Dalles.
Can I use my The Dalles ADU as a short-term rental (Airbnb / VRBO)? +
The Dalles currently permits short-term rentals in ADUs, subject to local registration requirements — Oregon has no statewide STR framework. Check with the Building Codes Services for any hosting platform limits or permit conditions that apply to your specific parcel.
Does The Dalles's seismic zone affect ADU construction requirements? +
The Dalles falls within Seismic Design Category C. 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 The Dalles'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 The Dalles? +
Building Codes Services handles ADU permit applications — online submission is available through the permit portal. Permit fees in The Dalles range from $3,000 to $4,500 depending on project scope and valuation. Our drawing sets are formatted specifically for The Dalles's submittal requirements to minimize plan check cycles.

More Services in The Dalles

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

Free · No Obligation

Not Sure If Your The Dalles Lot Qualifies?

Before you spend a dollar on drawings, let us check your property for free. We'll tell you honestly whether your The Dalles 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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