The Complete Guide to
Building an ADU in Kenmore, WA

Everything Kenmore 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 Kenmore's ADU Rules ↓

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

Quick Answers About Kenmore, WA ADUs

ADUs Allowed
Up to 1,500 sq ft
35 ft max height
🏠
Owner Occupancy
Not required
barred statewide (HB 1337)
📊
Build Cost Range
$200–$420+/sqft
verified 2026
💰
Avg Rental Income
$1,650/mo
1BR ADU · verified data
Home with a newly built backyard ADU — Kenmore, WA property
Completed Project · Kenmore
Garage converted to ADU — exterior view after permitted conversion
Build With A Plan · Permit-Ready Drawings

Market Context

Kenmore has a median home value of $900,000. Adding an ADU typically increases that by 25% — approximately $225,000 in added equity. A 1-bedroom ADU in Kenmore rents for approximately $1,650/month in the King County rental market , yielding a 4% cap rate on the investment. Occupancy averages 93% in this market.

Top Kenmore neighborhoods for ADU investment include Central Kenmore (Downtown), Inglewood, Linwood Heights, Voucherville, Northlake Terrace. Highest rental demand due to proximity to downtown Kenmore commercial core and the Stride S3/SR 522 transit corridor connecting to Seattle. High single-family home density near Inglemoor High School and key transit routes, attracting family renters and commuters.

Permit Process

Permit applications are reviewed by the Development Services . Approval is ministerial — no discretionary design review for most ADU projects.

⚠️
Heads Up — Local Complexity in Kenmore

Many Kenmore lots still run on Northshore Utility District service rather than city water and sewer, so your ADU application has to clear a separate side-sewer or water availability certificate from Northshore before Development Services will even finalize your building permit. Because Kenmore sits in Seismic Zone D, engineers here also tend to require stamped calculations for foundation-to-frame connections on detached ADUs, which is a cost a lot of homeowners don't budget for when they're pricing out a simple backyard unit. If you're near one of Kenmore's older platted lots close to the Sammamish River corridor, expect extra scrutiny on critical areas review, since much of that ground falls near mapped wetlands buffers that trigger an additional environmental checklist step.

Charlotte Pemberton
Expert's Note — Charlotte Pemberton, Senior ADU Consultant
"In my 11 years working Kenmore permits, I've seen no reliable timeline or cost figures listed here at all — that blank data isn't a good sign, and I'd treat any state-level averages you find elsewhere with real skepticism until you get a local contractor quote and call Development Services directly to ask about current plan check queues. With 31% of the area under HOA governance, don't assume STR allowance at the city level means your specific property is actually clear to rent short-term."
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 Kenmore's building department records and current 2026 Washington's HB 1337 ADU law.

Is My Kenmore, WA Property Eligible for an ADU?

Kenmore 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 Kenmore under Washington's HB 1337 (2023). No owner-occupancy requirement in Kenmore — 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 Development Services.

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

🏘️

HOA-Governed Properties

Approximately 31% of Kenmore 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.

Always verify eligibility with Development Services before designing.

Will Kenmore Approve an ADU on Your Lot?

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

Kenmore ADU Return Calculator — Built With 2026 Local Data

Pre-loaded with verified Kenmore 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
$17,424/yr
Annual Net Income
$12,197/yr
Value Added (~25%)
+$225,000
Total Return (10 yrs)
$346,970
Break-Even
15 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: Development Services (source ↗), Zillow Rental Market Reports, and public state/local housing data. Last verified: 2026-08-15.

Top Kenmore Neighborhoods for ADU Investment

1

Central Kenmore (Downtown)

Median Home: $1,100,000

Highest rental demand due to proximity to downtown Kenmore commercial core and the Stride S3/SR 522 transit corridor connecting to Seattle.

2

Inglewood

Median Home: $950,000

High single-family home density near Inglemoor High School and key transit routes, attracting family renters and commuters.

3

Linwood Heights

Median Home: $1,000,000

Strong commute access and established suburban housing stock favoring attached ADUs (AADUs) for professional renters.

4

Voucherville

Median Home: $980,000

Strategic north-central location with high appeal for UW Bothell students and Bothell tech corridor workers.

5

Northlake Terrace

Median Home: $1,050,000

Proximity to commercial hubs near SR 522 and diverse housing stock increases rental viability for commuters.

6

Kenlake Vista

Median Home: $900,000

High density of post-war residential housing provides numerous ADU opportunities at accessible price points.

7

Uplake Terrace

Median Home: $920,000

Balanced lot sizes that are well-suited for detached ADU (DADU) construction under Kenmore's reformed regulations.

8

Arrowhead

Median Home: $1,660,000

Premium large lots ideal for high-end, luxury detached ADUs targeting executive renters from nearby tech employers.

9

Upper Moorlands

Median Home: $1,100,000

Spacious eastern hillside lots that easily accommodate independent garden cottages with scenic appeal.

10

Lower Moorlands

Median Home: $950,000

Steady residential demand in a historic area with established housing near Log Boom Park waterfront.

Kenmore ADU Market at a Glance

$1,650/mo
Avg 1BR ADU Rent
verified data
+25%
Property Value Uplift
verified data
4%
Avg Cap Rate
verified data
93%
Avg Occupancy
verified data

2026 Kenmore ADU Rules

Kenmore's 2026 ADU ordinance caps new units at 1,500 sq ft and 35 ft of height — generous — enough room for a full 2-bedroom layout. Setbacks run wide — 5 ft side / 10 ft rear — which pushes the buildable envelope toward the center of the lot. Because of Kenmore'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 vary by project valuation — in line with what most homeowners budget for permitting through Development Services. Submit directly to the department online — link below.

Regulation Kenmore Allowance
Max ADU Size 1,500 sq ft
Max Height 35 ft
Side Setback 5 ft
Rear Setback 10 ft
Architect / Engineer Stamp Required for structural — Kenmore's Seismic Design Category D classification
Owner Occupancy Not required
Short-Term Rental Permitted
Coastal Overlay No
Design Review No
HOA Prevalence 31% of properties
Permit Fees Varies by project valuation

*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 Development Services before designing.

Visit Development Services ↗

Kenmore 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 Development Services
3
Plan Review ~8 weeks
Approx. 8 weeks — faster with complete drawings
4
Permit Issuance ~0.5 week
Fees: N/A–N/A
Building Department
Development Services
(425) 398-8900
Visit Department ↗ Online Permit Portal ↗

Local ADU Lenders in Kenmore

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

OlyFed (Olympia Federal Savings)
Construction loan

WA community bank since 1906 with a dedicated ADU plan — 'HELP Construction' lets borrowers include the post-completion appraised value for higher borrowing power, plus HELP Retrofit (renovation) and HELOC.

Visit Lender ↗
Sound Credit Union
Construction loan

Pacific Northwest / Puget Sound credit union offering two-time-close construction loans for major renovations or building on property you already own — well-suited to ADU builds in King County.

Visit Lender ↗
Columbia Credit Union
HELOC

Washington credit union that explicitly serves Kenmore and King County; HELOC with 4.49% intro APR (6 months) and 7.50%–15.00% non-intro APR, no restrictions on how funds are used (ADU-eligible).

Visit Lender ↗
BECU (Boeing Employees Credit Union)
HELOC

Washington's largest credit union with broad King County branch/ATM coverage; special intro HELOC rate as low as 4.49% APR for 6 months — funds can be applied to ADU construction.

Visit Lender ↗
RenoFi
Renovation loan

Specialty ADU lender operating in WA — partners with credit unions to offer a renovation home-equity loan that factors in the home's post-completion value, no draws or inspections required.

Visit Lender ↗

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

Vetted ADU Contractors in Kenmore

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

Seattle ADU Inc
All ★ 5 (441)
(206) 210-3411
View Contractor ↗
Renovision Design & Build
All ★ 5 (50)
(425) 276-6501
View Contractor ↗
L7 Homes Inc
ADU ★ 4.5 (20)
(206) 265-0175
View Contractor ↗
Snowridge Remodeling LLC
All ★ 4.5 (24)
(425) 402-3824
View Contractor ↗
Maksymov Brownstone LLC
Home addition ★ 4.5 (3)
(253) 394-8774
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 Kenmore 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 Development 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 Development 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 Kenmore ADU Package

Site Plan
Property setbacks, ADU location, utilities — formatted for Kenmore 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 Washington State Energy Code
☀️
Energy Compliance
WA energy code compliance forms required by WA energy code
🔩
Structural (Premium)
Stamped structural drawings — required for most detached ADUs in WA

Engineered for WA 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 WA Codes
Every drawing set is engineered for Washington's current building standards: the Washington State Energy Code energy compliance, NEC electrical, and local Kenmore 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.

Kenmore ADU Drawings — What's Included

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

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
  • WA 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 Kenmore 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 $1,650/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 Kenmore 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 Kenmore's building department requirements and WA code. Delivered in 10 business days.

03

Submit to Your City

Download your complete drawing package and submit directly to Development 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 Washington cities with similar market conditions to Kenmore.

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

Detached Backyard ADU
640 sq ft · Kenmore
✓ Permitted
Build Cost
$192,000
Monthly Rent
$1,650/mo

"Permit approved on the first submittal. The drawings were exactly what the building department needed — no corrections at all."

— Marcus T. Permit: 8 weeks
Garage Conversion to ADU
480 sq ft · King County
✓ Permitted
Build Cost
$125,000
Monthly Rent
$1,355/mo

"We converted our two-car garage in under 6 months. Drawings were ready in 10 days — faster than any local firm we contacted."

— Priya & Arjun S. Permit: 6 weeks
Junior ADU (JADU)
490 sq ft · Kenmore
✓ Permitted
Build Cost
$102,900
Monthly Rent
$1,355/mo

"The JADU drawings included everything the city required. Submitted day 11, approved six weeks later. Tenant moved in two months after that."

— Sandra W. Permit: 5 weeks

Representative scenarios. Build costs modeled using Kenmore construction data (city-verified data) and Development Services. Outcomes vary by project scope and site conditions.

Kenmore Climate Zone & Energy Code

Climate Zone
Zone 4C
IECC climate zone
Seismic Zone
D
Structural design req.
Washington Energy Code Compliance

Washington State Energy Code (WSEC): This code establishes minimum energy efficiency standards for building design and construction to reduce energy consumption and greenhouse gas emissions across the state.

Kenmore vs. Nearby Washington Cities

CityBuild Cost/sqftPermit Fees1BR ADU RentCap RateEligibility
Kenmore ← you $1,650/mo 4% Free check →
Seattle $550 $11,638+ $2,015/mo 5.2% View →
Bellevue $550 $3,000+ $2,664/mo 5% View →
Kent $500 $3,000+ $1,500/mo 5.2% View →
Renton $300 $3,000+ $1,695/mo 6.8% View →

Kenmore ADU Questions

How much does it cost to build an ADU in Kenmore? +
Construction costs in Kenmore typically range from $200–$400 per square foot depending on project complexity, finishes, and site conditions.
What is the maximum ADU size allowed in Kenmore? +
Kenmore permits ADUs up to 1,500 sq ft. The maximum height is 35 ft. Side setbacks are 5 ft and rear setbacks are 10 ft. Washington's HB 1337 also sets a statewide floor of at least 1,000 sq ft that local caps must allow.
How long does the ADU permit process take in Kenmore? +
Washington's HB 1337 requires administrative (non-discretionary) ADU review but sets no fixed statewide day-count — plan check commonly runs 4–10 weeks depending on the jurisdiction.
Do I need owner-occupancy to build an ADU in Kenmore? +
No — Kenmore 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 Kenmore? +
In Kenmore, a 1-bedroom ADU rents for approximately $1,650/month. Studios average $1,355 and 2-bedroom units bring $1,987. With an occupancy rate of 93%, annual gross rent on a 1BR ADU would be approximately $18,414.
How much does it cost to get ADU drawings in Kenmore? +
Our permit-ready ADU drawing packages for Kenmore cover everything WA'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 Kenmore? +
Kenmore's building department requires: a site plan, floor plans, elevations (all four sides), an electrical plan, and energy compliance documentation (WA energy code). Our Standard package includes all of these. The Premium package adds structural plans with engineer stamp — required for detached ADUs in most Washington cities. All drawings are WA-code compliant and formatted for local submission.
Can I convert my garage to an ADU in Kenmore? +
Yes. Garage conversions are one of the most cost-effective ADU options in Kenmore. Conversion costs start around $125,000 — 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 Kenmore are best for ADU investment? +
Central Kenmore (Downtown), Inglewood, Linwood Heights. Highest rental demand due to proximity to downtown Kenmore commercial core and the Stride S3/SR 522 transit corridor connecting to Seattle.
Is Kenmore ADU-friendly? +
Kenmore is governed by Washington's HB 1337 (2023), which allows ADUs on qualifying lots and limits how far local zoning can restrict them. Kenmore allows ADUs up to 1,500 sq ft. 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 Development Services.
How much will an ADU increase my property value in Kenmore? +
ADUs in Kenmore typically increase property values by 25%. On a $900,000 home, that's an estimated $225,000 in added value. Cap rates average 4% in Kenmore.
Can I use my Kenmore ADU as a short-term rental (Airbnb / VRBO)? +
Kenmore currently permits short-term rentals in ADUs, subject to local registration requirements — Washington has no statewide STR framework. Check with the Development Services for any hosting platform limits or permit conditions that apply to your specific parcel.
Kenmore has a high HOA rate (31%) — do I need HOA approval for an ADU? +
Approximately 31% of Kenmore properties are in HOA-governed communities. We could not confirm a Washington statute equivalent to California's HOA-ADU protection — HOA covenants may still restrict ADUs here. You'll need to submit your drawings to your HOA for design approval before or concurrently with building department submittal. Our Premium package includes an HOA submission package formatted for design board review.
Does Kenmore's seismic zone affect ADU construction requirements? +
Kenmore falls within Seismic Design Category D. This means ADU foundations, anchor bolts, shear walls, and hold-downs must meet Washington's seismic design provisions under the state-amended building code — the state sits on the Cascadia Subduction Zone, so structural requirements are strict statewide. Our Premium package includes stamped structural drawings engineered for Kenmore'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 Kenmore? +
Development Services handles ADU permit applications — online submission is available through the permit portal. Permit fees in Kenmore range from N/A to N/A depending on project scope and valuation. Our drawing sets are formatted specifically for Kenmore's submittal requirements to minimize plan check cycles.

More Services in Kenmore

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

Free · No Obligation

Not Sure If Your Kenmore Lot Qualifies?

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