The Complete Guide to
Building an ADU in Tigard, OR

Everything Tigard 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 Tigard's ADU Rules ↓

Created by Build With A Plan · Drawings from $997 (more below)

Quick Answers About Tigard, OR ADUs

ADUs Allowed
Up to 800 sq ft
25 ft max height
🏠
Owner Occupancy
Not required
CA state law applies
📊
Average Build Cost
$300/sqft
verified 2026
💰
Avg Rental Income
$1,421/mo
1BR ADU · verified data
California home with a newly built backyard ADU — Tigard property
Completed Project · Tigard
Garage converted to ADU — exterior view after permitted conversion
Build With A Plan · Permit-Ready Drawings from $997

Market Context

Tigard has a median home value of $479,000. Adding an ADU typically increases that by 25.0% — approximately $119,750 in added equity. A 1-bedroom ADU in Tigard rents for approximately $1,421/month in the Washington County rental market , yielding a 5.2% cap rate on the investment. Occupancy averages 95.0% in this market.

Top Tigard neighborhoods for ADU investment include West Tigard, East Bull Mountain, Derry Dell, Tigard Triangle, Downtown Tigard. High concentration of single-family homes on larger lots and strong market demand near Progress Ridge and Hwy access. Large, newer single-family lots on Bull Mountain provide room for detached ADUs and strong owner-renter demand.

Permit Process

Permit applications are reviewed by the Building Division , with a plan check timeline of approximately 7 weeks. Permit fees in Tigard range from $23,549 to $25,893 depending on project scope. Design review: Yes - in historic districts only

Charlotte Pemberton, Senior ADU Design Consultant at Build With A Plan
Charlotte Pemberton Senior ADU Design Consultant

11 years in California residential permitting and ADU documentation. This guide was researched and verified against Tigard's building department records and current 2026 California ADU law.

Is My Tigard, OR Property Eligible for an ADU?

Tigard homeowners benefit from California's state ADU law — one of the most permissive frameworks in the country since 2020. Here's what applies to your property before you start designing.

Single-Family Home

Permitted on single-family lots in Tigard under California state law. No owner-occupancy requirement in Tigard — you can rent both units as investment properties. Ministerial permit approval — no neighbor input or discretionary design review.

Multi-Family Property

Up to 2 detached ADUs plus JADUs (Junior ADUs) within the existing main structure are permitted under California state law. Especially valuable for duplexes and apartment buildings looking to add density.

🏘️

HOA-Governed Properties

Approximately 26% of Tigard homes are in an HOA. California law (AB 670) prohibits HOAs from banning ADUs outright, but they can impose reasonable architectural standards. Our drawings include HOA submission formatting.

🏛️

Historic Districts

Yes - in historic districts only

Always verify eligibility with Building Division before designing.

Tigard ADU Return Calculator — Built With 2026 Local Data

Pre-loaded with verified Tigard 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
$15,006/yr
Annual Net Income
$10,504/yr
Value Added (~25.0%)
+$119,750
Total Return (10 yrs)
$224,790
Break-Even
18 years

* Estimates only. Assumes ~85% occupancy, ~30% expense ratio, 25.0% property value uplift. Consult a financial advisor before investing.

Data sources: Tigard Development Services Department, Zillow Rental Market Reports, local appraiser records. Last verified: 2026-05-30.

Top Tigard Neighborhoods for ADU Investment

1

West Tigard

Median Home: $791,662

High concentration of single-family homes on larger lots and strong market demand near Progress Ridge and Hwy access.

2

East Bull Mountain

Median Home: $784,000

Large, newer single-family lots on Bull Mountain provide room for detached ADUs and strong owner-renter demand.

3

Derry Dell

Median Home: $635,450

Leafy suburb with spacious lots and many single-family homes making ADU siting straightforward.

4

Tigard Triangle

Median Home: $641,000

Walkable area near downtown and services with strong rental demand from commuters and nearby jobs.

5

Downtown Tigard

Median Home: $590,446

Close to Main Street jobs, transit and amenities driving rental demand for ADUs.

6

Cook Park

Median Home: $586,622

Established single-family neighborhood with parks and lot sizes suitable for detached ADUs.

7

Scholls-Summerlake

Median Home: $580,201

Suburban lots and proximity to Progress Ridge/Bridgeport make it attractive to renters.

8

Durham Road

Median Home: $567,263

Good access to Bridgeport Village and highways; many single-family properties with ADU potential.

9

Greenburg Road

Median Home: $546,034

Single-family streets with moderate home values and access to Fanno Creek Trail and transit.

10

Southview

Median Home: $539,799

Stable single-family neighborhood close to highways and regional job centers supporting rental demand.

Tigard ADU Market at a Glance

$1,421/mo
Avg 1BR ADU Rent
verified data
+25.0%
Property Value Uplift
verified data
5.2%
Avg Cap Rate
verified data
95.0%
Avg Occupancy
verified data

Tigard ADU Zoning Regulations

Regulation Tigard Allowance
Max ADU Size 800 sq ft
Max Height 25 ft
Side Setback 0.0 ft
Rear Setback 5.0 ft
Owner Occupancy Not required
Short-Term Rental Restricted
Coastal Overlay No
Design Review Yes - in historic districts only
HOA Prevalence 26% of properties

Data verified recently. Always confirm with the Building Division before designing.

Tigard ADU Permit Timeline & Fees

ℹ Timeline and fee estimates are based on California state averages. Actual Tigard data coming soon.

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 ~7 weeks
Approx. 7 weeks — faster with complete drawings
4
Permit Issuance ~0.5 week
Fees: $23,549–$25,893
Building Department
Building Division
(503) 718-2439
Visit Department ↗ Online Permit Portal ↗

Local ADU Lenders in Tigard

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

Unitus Community Credit Union
HELOC

Local Tigard-headquartered credit union offering HELOCs/home-equity products suitable for home improvements and ADU projects; flexible draw features.

Visit Lender ↗
OnPoint Community Credit Union
HELOC

Large Oregon-based credit union (branches in the Tigard/Portland area) offering HELOCs for home repair and improvement projects.

Visit Lender ↗
Rivermark Community Credit Union
HELOC

Regional credit union offering HELOCs with a $5,000 minimum and typical draw/repayment structure (10-year draw / 20-year repay), suitable for larger ADU/renovation financing.

Visit Lender ↗
RenoFi (specialty ADU/renovation lender)
Renovation loan

Specialty ADU/renovation lender that partners with credit unions in Oregon to arrange ADU construction/renovation financing; used by credit unions to fund ADUs.

Visit Lender ↗
Banner Bank
HELOC

Regional bank active in Oregon offering HELOCs for renovations and major home projects; draws as-needed and interest-only during draw period.

Visit Lender ↗

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

Vetted ADU Contractors in Tigard

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

JDI Construction
All ★ 4.8 (391)
(360) 309-9571
View Contractor ↗
SLS Custom Homes & Remodeling
ADU
(503) 713-6207
View Contractor ↗
Development Contracting LLC
All
View Contractor ↗
TGR General Construction
Home addition
(503) 270-0195
View Contractor ↗
Suite Additions
ADU
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 Tigard 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

$997 – $1,997

  • 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 ↓

What's Included in Your Tigard ADU Package

Site Plan
Property setbacks, ADU location, utilities — formatted for Tigard submittal
📐
Floor Plans
Dimensioned layouts for all levels with room labels, egress windows, door schedules
🏠
Elevations (4 sides)
Exterior elevations showing materials, roof pitch, height compliance
Electrical Plan
Outlet, switch, and panel layout per NEC and California Title 24
☀️
Energy Compliance
Title 24 Part 6 compliance forms required by OR energy code
🔩
Structural (Premium)
Stamped structural drawings — required for most detached ADUs in CA

Engineered for OR Permit Approvals

Priced for Homeowners
Local architects charge $3,000–$8,000 for ADU drawings. Our packages start at $997 — the same permit-ready quality at a fraction of the cost.
Built for OR Codes
Every drawing set is engineered for California's current building standards: Title 24 energy compliance, CBC, NEC electrical, and local Tigard 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.

Tigard ADU Drawing Costs — Compared

What homeowners typically pay for permit-ready ADU drawings in Tigard, by service type:

Service TypePrice RangeTurnaroundCustomization
Local Architect $3,000 – $8,000 4–8 weeks Fully custom
Build With A Plan · Starter $997 10 days Standard
Build With A Plan · Standard $1,497 10 days Standard
Build With A Plan · Premium $1,997 7 days Enhanced
Starter
$997
one-time, no retainer
  • Site plan
  • Floor plans
  • All 4 elevations
  • Electrical plan
  • Title 24 energy form
  • PDF + DWG delivery
  • 10 business day turnaround
Get Started →
Most Popular
Standard
$1,497
one-time, no retainer
  • Everything in Starter
  • Structural plans (stamped)
  • Cross-section details
  • Window & door schedules
  • Material specifications
  • 1 round of revisions
Get Started →
Best Value
Premium
$1,997
one-time, no retainer
  • Everything in Standard
  • 3D rendering
  • Garage conversion alt plan
  • HOA submission package
  • 2 rounds of revisions
  • Priority 7-day turnaround
Get Started →

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 Tigard'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 real project outcomes from clients who used our permit-ready drawing sets across California.

Detached Backyard ADU
640 sq ft · Tigard
✓ Permitted
Build Cost
$192,000
Monthly Rent
$1,421/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: 7 weeks
Garage Conversion to ADU
480 sq ft · Washington County
✓ Permitted
Build Cost
$110,000
Monthly Rent
$1,404/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 · Tigard
✓ Permitted
Build Cost
$110,250
Monthly Rent
$1,404/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

Client first names and last initials only. Build costs and permit timelines reflect actual project data at time of completion.

Tigard Climate Zone & Energy Code

Climate Zone
Zone 4C
CA Title 24 zone
Seismic Zone
Seismic Design Category D (per Oregon Structural Specialty Code / ASCE 7); site-specific SDC must be calculated using ASCE 7/OSSC maps and site soil parameters.
Structural design req.
California Title 24 Energy Compliance

Oregon Residential Specialty Code (ORSC) — Chapter 11 contains the state residential energy provisions (2023 ORSC; mandatory April 1, 2024) that apply to ADUs and sets prescriptive and performance requirements for envelope, insulation, HVAC, lighting and service water heating.

Tigard vs. Nearby Oregon Cities

CityBuild Cost/sqftPermit Fees1BR ADU RentCap RateDrawings
Tigard ← you $300 $23,549+ $1,421/mo 5.2% From $997
Hillsboro $280 $17,551+ $1,594/mo 6.0% View →
Beaverton $275 $2,500+ $1,511/mo 6.2% View →
Tualatin $300 $19,885+ $1,614/mo 3.9% View →
Forest Grove $350 $2,500+ $1,375/mo 5.5% View →

Tigard ADU Questions

How much does it cost to build an ADU in Tigard? +
Construction costs in Tigard average $300 per square foot based on 2026 data. A typical 600 sq ft ADU runs approximately $180,000, while a 1,000 sq ft unit costs around $300,000. Garage conversions start lower, around $110,000 base.
What is the maximum ADU size allowed in Tigard? +
Tigard permits ADUs up to 800 sq ft. The maximum height is 25 ft. Side setbacks are 0.0 ft and rear setbacks are 5.0 ft. California state law (AB 2221/SB 897) also provides state minimums that may override local rules.
How long does the ADU permit process take in Tigard? +
Plan check in Tigard typically takes 7 weeks (estimated based on California state averages). Permit fees range from $23,549 to $25,893. Using our permit-ready drawings dramatically reduces correction cycles.
Do I need owner-occupancy to build an ADU in Tigard? +
No — Tigard 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 Tigard? +
In Tigard, a 1-bedroom ADU rents for approximately $1,421/month. Studios average $1,404 and 2-bedroom units bring $1,745. With an occupancy rate of 95.0%, annual gross rent on a 1BR ADU would be approximately $16,199.
How much does it cost to get ADU drawings in Tigard? +
Our permit-ready ADU drawing packages for Tigard start at $997 — compared to $3,000–$8,000 for a local architect. Every set is engineered for OR code compliance and designed to pass your local building department's plan check. Turnaround is 10 business days with a 14-day money-back guarantee.
What drawings are included in the permit set? +
Our Standard package includes everything Tigard's building department requires: site plan, floor plans, elevations (all four sides), electrical plan, and energy compliance (Title 24). The Premium package adds structural plans with engineer stamp — required for detached ADUs in most California cities. All drawings are OR-code compliant and formatted for local submission.
Can I convert my garage to an ADU in Tigard? +
Yes. Garage conversions are one of the most cost-effective ADU options in Tigard. Conversion costs start around $110,000 — 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 Tigard are best for ADU investment? +
West Tigard, East Bull Mountain, Derry Dell. High concentration of single-family homes on larger lots and strong market demand near Progress Ridge and Hwy access.
Is Tigard ADU-friendly? +
Tigard is governed by California state ADU law, one of the most permissive in the country. Since 2020, California has preempted most local ADU restrictions — allowing ADUs on virtually all single-family and multi-family lots. Tigard allows ADUs up to 800 sq ft. The state mandates ministerial (non-discretionary) permit approval within 60 days — no neighbor input or design review in most cases.
How much will an ADU increase my property value in Tigard? +
ADUs in Tigard typically increase property values by 25.0%. On a $479,000 home, that's an estimated $119,750 in added value. Cap rates average 5.2% in Tigard.
Can I use my Tigard ADU as a short-term rental (Airbnb / VRBO)? +
Tigard restricts short-term rentals (under 30 days) in ADUs. The unit can be rented long-term — a 12-month lease is the most straightforward path. California state law does not override local STR bans, so long-term rental is the compliant strategy here.
Does Tigard's seismic zone affect ADU construction requirements? +
Tigard falls within Seismic Design Category Seismic Design Category D (per Oregon Structural Specialty Code / ASCE 7); site-specific SDC must be calculated using ASCE 7/OSSC maps and site soil parameters.. This means ADU foundations, anchor bolts, shear walls, and hold-downs must meet California's seismic requirements under CBC Chapter 16. Our Premium package includes stamped structural drawings engineered for Tigard'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 Tigard? +
Building Division handles ADU permit applications — online submission is available through the permit portal. Permit fees in Tigard range from $23,549 to $25,893 depending on project scope and valuation. Plan check typically takes 7 weeks. Our drawing sets are formatted specifically for Tigard's submittal requirements to minimize plan check cycles.

More Services in Tigard

Garage Conversion Drawings Convert your Tigard garage to permitted living space. From $997. View Package → Home Addition Drawings Room additions, second stories, and bump-outs for Tigard properties. View Package → Start Your Tigard Project Permit-ready drawings in 10 business days. 14-day money-back guarantee. Order Now →

Start Your Tigard ADU Today

Permit-ready drawings from $997. Delivered in 10 business days. Designed for Tigard's building department. 14-day money-back guarantee.

Get My ADU Drawings →

Questions? Your coordinator responds within 4 business hours.