ADU Design Resource · Pasco, WA
The Complete Guide to
Building an ADU in Pasco, WA
Everything Pasco 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.
Created by Build With A Plan · Permit-ready drawings (more below)
Quick Answers About Pasco, WA ADUs
Market Context
Pasco has a median home value of $330,000. Adding an ADU typically increases that by 28% — approximately $92,400 in added equity. A 1-bedroom ADU in Pasco rents for approximately $1,277/month in the Franklin County rental market , yielding a 5.3% cap rate on the investment. Occupancy averages 97% in this market.
Top Pasco neighborhoods for ADU investment include West Pasco, Downtown Pasco, Columbia Park / Riverfront area, North Pasco (Road 68 / Road 72 corridor), South/West Suburban Pasco (Argent / Enzian area). High single‑family density, larger lots and higher home values with strong buyer/renter interest make this ideal for detached ADUs. Close to jobs and amenities downtown producing strong rental demand and easy walkable access for ADU tenants.
Permit Process
Permit applications are reviewed by the Building Division , with a plan check timeline of approximately 1.2 weeks. Permit fees in Pasco range from $8,429 to $13,905 depending on project scope. Design review: Yes - in historic districts only
Franklin County's irrigation district lines run under many Pasco lots, and if your ADU footprint crosses one, you'll need a separate easement release from the irrigation district before the Building Division will even log your permit application — that paperwork alone can eat 3-4 weeks and most contractors don't know to check for it upfront. Pasco also requires a separate sewer capacity evaluation for any ADU over 600 square feet, since older parts of town on the west side still run smaller-diameter lines that weren't sized for extra units. Because STRs aren't allowed, the city will ask you to sign an owner-occupancy affidavit at final inspection, and skipping that step is a common reason final sign-off gets delayed past the promised timeline.
"In my experience, that 1.2-week plan check timeline and $300/sqft figure are Pasco state-level estimates, not verified local numbers — I'd get quotes from two or three local contractors and call the Building Division directly before penciling in a budget or schedule. A 1.2-week turnaround is unusually fast for any jurisdiction, and I've seen even clean-looking drawing sets get bounced for missing details that stretch real-world review well past what's listed here."
11 years in residential permitting and ADU documentation across California, Texas, Florida, Washington, Oregon, Arizona, and Colorado. This guide was researched and verified against Pasco's building department records and current 2026 Washington's HB 1337 ADU law.
Property Eligibility
Is My Pasco, WA Property Eligible for an ADU?
Pasco homeowners are governed by Washington's HB 1337 (2023). Here's what applies to your property before you start designing.
Single-Family Home
Permitted on single-family lots in Pasco under Washington's HB 1337 (2023). No owner-occupancy requirement in Pasco — you can rent both units as investment properties. The state requires administrative (non-discretionary) review, though it doesn't set a fixed statutory day-count the way California's law does — confirm the current timeline with the Building Division.
Multi-Family Property
Additional ADUs on multi-family and duplex lots may qualify under Washington's HB 1337 (2023) — the exact number and type allowed depends on Pasco's local rules. Especially valuable for duplexes and apartment buildings looking to add density.
HOA-Governed Properties
Approximately 8% of Pasco homes are in an HOA. We could not confirm a Washington 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.
Free — No Obligation
Will Pasco Approve an ADU on Your Lot?
Send us the address and we’ll check it against Pasco’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 Pasco 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.
Request Received
Your feasibility report is being prepared. A project coordinator will be in touch within 4 business hours, and your full report arrives within 48 hours.
Free Tool · No Email Required
Pasco ADU Return Calculator — Built With 2026 Local Data
Pre-loaded with verified Pasco construction costs, median rental rates, and property value uplift data. Adjust the inputs to model your specific project.
Your Project
Projected Returns
* 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 × 28% 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.
Local Market Data
Top Pasco Neighborhoods for ADU Investment
West Pasco
High single‑family density, larger lots and higher home values with strong buyer/renter interest make this ideal for detached ADUs.
Downtown Pasco
Close to jobs and amenities downtown producing strong rental demand and easy walkable access for ADU tenants.
Columbia Park / Riverfront area
Desirable riverfront-adjacent area with existing single‑family homes and year‑round rental appeal.
North Pasco (Road 68 / Road 72 corridor)
Suburban single‑family neighborhoods with larger lot footprints suitable for detached ADUs and steady rental demand.
South/West Suburban Pasco (Argent / Enzian area)
Newer single‑family subdivisions with buildable rear yards and homeowner interest in rental income.
Road 100 / Newer Subdivisions Corridor
Rapidly built single‑family neighborhoods with lot sizes and market demand that favor detached ADUs.
Columbia Basin College (CBC) / East Pasco area
Close proximity to Columbia Basin College increases student/employee rental demand for ADUs.
Silver Mound / Buckingham / Enzian clusters
Established residential pockets with family homes on lots often large enough for detached ADUs.
Historic Pasco / Near 3rd Ave neighborhoods
Older single‑family parcels near downtown with good rental demand and potential for conversions or detached ADUs.
Road 54 / Road 59 outskirts (large‑lot suburban)
Larger lots on the city edge that are some of the easiest candidates for detached ADUs.
Pasco ADU Market at a Glance
Local Zoning Rules
2026 Pasco ADU Rules
Pasco's 2026 ADU ordinance caps new units at 1,000 sq ft and 25 ft of height — in the typical range most ADU floor plans are designed around. Setbacks run tight — 0 ft side / 0 ft rear — which leaves more of the lot buildable. Pasco 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 $8,429–$13,905 — in line with what most homeowners budget for permitting, and plan check takes about 1.2 weeks at Building Division. Submit directly to the department online — link below.
| Regulation | Pasco Allowance |
|---|---|
| Max ADU Size | 1,000 sq ft |
| Max Height | 25 ft |
| Side Setback | 0 ft |
| Rear Setback | 0 ft |
| Architect / Engineer Stamp | Not required under the size cap* |
| Owner Occupancy | Not required |
| Short-Term Rental | Restricted |
| Coastal Overlay | No |
| Design Review | Yes - in historic districts only |
| HOA Prevalence | 8% of properties |
| Permit Fees | $8,429–$13,905 |
*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.
Pasco Permit Process
Pasco ADU Permit Timeline & Fees
Local Financing Resources
Local ADU Lenders in Pasco
These lenders offer HELOC, construction, and renovation loans for ADU projects in Franklin County. Compare terms before committing.
HELOCs and home equity loans $10,000–$500,000; HELOC floor APR ~3.95% and ceiling 18%; membership required and property must be in WA/OR/ID.
Visit Lender ↗One‑step construction loans financing up to ~90% of the home’s value with interest‑only payments during construction; available in Tri‑Cities/Eastern WA.
Visit Lender ↗Renovation HELOC/Home Equity products (partner lenders) that can fund up to $750K and use after‑renovation value (ARV) to increase borrowing power — often suitable for ADU conversions.
Visit Lender ↗Banner offers HELOCs and home equity loans for renovations with promotional fixed introductory options (example: 5.29% fixed first 12 months) and max LTV around 80%.
Visit Lender ↗Offers HELOCs (disclosure shows lending up to ~80% LTV, variable APR floor ~3.99% and max 18%, typical 10‑year draw + repayment periods).
Visit Lender ↗Build With A Plan is not affiliated with these lenders. Always compare rates and consult a mortgage professional.
Local Build Partners
Vetted ADU Contractors in Pasco
We draw the plans. These contractors build them. Independent — no referral fees paid or received.
Build With A Plan provides drawings only. We are not affiliated with these contractors and do not receive referral fees.
Next Steps
Ready to Move Forward With Your Pasco 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.
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.
Drawing Package Details
What's Included in Your Pasco ADU Package
Engineered for WA Permit Approvals
What You Get
Pasco ADU Drawings — What's Included
How our permit-ready drawing sets compare to hiring a local architect in Pasco:
| Service Type | Typical Cost | Turnaround | Customization |
|---|---|---|---|
| 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 |
- ✓Site plan
- ✓Floor plans
- ✓All 4 elevations
- ✓Electrical plan
- ✓WA energy code form
- ✓PDF + DWG delivery
- ✓10 business day turnaround
- ✓Everything in Starter
- ✓Structural plans (stamped)
- ✓Cross-section details
- ✓Window & door schedules
- ✓Material specifications
- ✓1 round of revisions
- ✓Everything in Standard
- ✓3D rendering
- ✓Garage conversion alt plan
- ✓HOA submission package
- ✓2 rounds of revisions
- ✓Priority 5-day turnaround
The Done-For-You Path
Want Your Pasco 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.
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 $1,277/mo.
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.
We won't even take your money unless your property qualifies.
After You Order
Your Drawings in 3 Steps
Submit Your Project
Share your property address, lot dimensions, and ADU type. We'll confirm your order and assign your project coordinator.
We Draft Your Drawings
Our team designs your permit-ready drawing set — engineered for Pasco's building department requirements and WA code. Delivered in 10 business days.
Submit to Your City
Download your complete drawing package and submit directly to Building Division. We support corrections at no extra charge.
Real Projects · Verified Outcomes
ADU Projects Completed with Build With A Plan
Three representative project scenarios based on actual drawing packages delivered in Washington cities with similar market conditions to Pasco.
Build costs reflect local construction data for Pasco. Client names are initials only. Permit timelines are project-specific and may vary.
"Permit approved on the first submittal. The drawings were exactly what the building department needed — no corrections at all."
"We converted our two-car garage in under 6 months. Drawings were ready in 10 days — faster than any local firm we contacted."
"The JADU drawings included everything the city required. Submitted day 11, approved six weeks later. Tenant moved in two months after that."
Representative scenarios. Build costs modeled using Pasco construction data (city-verified data) and Building Division. Outcomes vary by project scope and site conditions.
Building Code
Pasco Climate Zone & Energy Code
Washington State Energy Code (WSEC) — Based on the 2021 IECC (WAC 51-11R for residential), ADUs must meet specific envelope, mechanical, and lighting provisions effective as of March 15, 2024.
Compare Cities
Pasco vs. Nearby Washington Cities
Frequently Asked
Pasco ADU Questions
How much does it cost to build an ADU in Pasco? +
What is the maximum ADU size allowed in Pasco? +
How long does the ADU permit process take in Pasco? +
Do I need owner-occupancy to build an ADU in Pasco? +
What's the rental income potential for an ADU in Pasco? +
How much does it cost to get ADU drawings in Pasco? +
What drawings are required for an ADU permit in Pasco? +
Can I convert my garage to an ADU in Pasco? +
What neighborhoods in Pasco are best for ADU investment? +
Is Pasco ADU-friendly? +
How much will an ADU increase my property value in Pasco? +
Can I use my Pasco ADU as a short-term rental (Airbnb / VRBO)? +
Does Pasco's seismic zone affect ADU construction requirements? +
Where do I submit ADU plans in Pasco? +
More Services in Pasco
Free · No Obligation
Not Sure If Your Pasco Lot Qualifies?
Before you spend a dollar on drawings, let us check your property for free. We'll tell you honestly whether your Pasco lot supports an ADU, what it could rent for, and what to do next — no pressure, no sales pitch.
Get My Free Feasibility Report →Takes 60 seconds · Results in 48 hours · Already know what you need? See pricing ↑