Home Addition Drawings · Bothell, WA
Permit-Ready Home Addition
Drawings for Bothell, WA
Expand your home with a permitted room addition, second story, or family room extension. We deliver complete, code-compliant drawing sets for Bothell's building department — in 10 business days, starting at $1,497.
14-day money-back guarantee · 10 business day turnaround
Local Intelligence
What Bothell Homeowners Need to Know Before Submitting
Size & Zoning Rules
Any new square footage added to your Bothell home counts against the same zoning envelope that governs ADU size, meaning large additions may affect your ability to add a future ADU. Bothell's current ADU size cap is 1,200 sq ft — generous enough to accommodate most project types.
Bothell does not impose an owner-occupancy requirement, so you can rent both the main home and any ADU or conversion as investment units.
If the addition creates a second unit or is later converted to a rental, Bothell's ADU market supports approximately $2,438/month for a 2-bedroom unit.
Permit Process & Fees
Building and Permit Services Division permit fees for this project type typically range from $26,652 to $31,110 depending on project valuation and scope. Plan check runs approximately 7 weeks — though each correction cycle adds 3–6 weeks, which is why code-compliant drawings matter so much.
Addition permit packages submitted to Building and Permit Services Division must include a site plan, floor plans, all four elevations, an electrical plan, and energy compliance documentation — plus stamped structural drawings are always required for any load-bearing elements, second-story work, or new foundation.
Visit Building and Permit Services Division ↗Construction Cost Context
Bothell's home addition construction costs run $210–$420 per square foot — a wide range driven by labor markets, local code complexity, and finish level. Our drawings are priced at a fraction of what a full-service architect would charge to produce the same permit set.
⚠ Common Pitfall in Bothell
Because Bothell straddles both Snohomish and King County lines, your parcel's exact jurisdiction determines which fee schedule and setback rules apply — and some streets have had properties get bounced between the two departments before landing with the right reviewer. Since the city sits in Seismic Zone D2, expect the structural review to scrutinize your foundation-to-framing connections closely, especially if you're building a detached ADU over an existing sloped backyard, which can add a few weeks if your engineer's calculations don't match Bothell's specific checklist. Also, older neighborhoods like those near Downtown Bothell often have undersized sewer laterals from the 1960s-70s, so budget for a sewer scope inspection early — discovering a clay pipe needs replacing after your permit is already submitted can stall the project for a month or more.
Expert Verdict — Marcus Reid, Licensed Designer
"In my experience working with Bothell homeowners, that 7-week plan check timeline and $300/sqft build cost are state-level estimates, not verified local figures — I'd call the Building and Permit Services Division directly and get a couple of local contractor bids before penciling in a budget or schedule. Even setting cost aside, I've rarely seen a complete-first-try drawing set clear review in under 7 weeks; incomplete submittals are the norm and can easily push that timeline out several more weeks. — Charlotte Pemberton, Senior ADU Design Consultant"
Market Context
Bothell has a median home value of $900,000. Comparable renovation projects in this market typically add 28% to resale value.
Neighborhoods in Bothell with the strongest home addition and resale value potential include Norway Hill, North Creek, Downtown Bothell, Westhill, Morningside. Close to UW Bothell with large median lot sizes and many single-family homes ideal for detached ADUs.
Permit Process
Permit applications are reviewed by the Building and Permit Services Division, with a plan check timeline of approximately 7 weeks. Permit fees in Bothell range from $26,652 to $31,110 depending on project scope. Design review: Yes - in historic districts only.
Bothell falls within Seismic Design Category D2, which affects structural requirements for any new addition tying into the existing structure.
Local Financing Resources
Local Home Addition Lenders in Bothell
These lenders offer HELOC, construction, and renovation loans for home addition projects in King County. Compare terms before committing.
Local Sound CU Bothell branch offers home equity loans/HELOCs for renovations — contact branch for amounts/terms.
Visit Lender ↗Offers HELOCs for home renovation projects; current HELOC rates listed ~6.99%–9.84% APR (as of 2026-05-01).
Visit Lender ↗Salal’s Custom Fit HELOC provides a variable-rate line and up to five lockable fixed-rate segments useful for staged ADU construction.
Visit Lender ↗Local bank headquartered in Bothell offering home loans, HELOCs and construction/home-improvement financing through its mortgage services.
Visit Lender ↗Specialty ADU/renovation financing platform — RenoFi loans commonly cover up to $750k in renovation costs and have an ADU-specific program.
Visit Lender ↗Build With A Plan is not affiliated with these lenders. Always compare rates and consult a mortgage professional.
Local Build Partners
Vetted Home Addition Contractors in Bothell
We draw the plans. These contractors build the addition. 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.
Drawing Package Details
What's Included in Your Bothell Home Addition Package
Transparent Pricing
Bothell Home Addition Drawing Packages
One-time fee. No retainer. No hourly billing.
- ✓Site plan
- ✓Floor plans (existing + proposed)
- ✓All 4 elevations
- ✓Electrical plan
- ✓Title 24 energy compliance
- ✓PDF + DWG delivery
- ✓10 business day turnaround
- ✓Everything in Starter
- ✓Stamped structural drawings
- ✓Foundation plan
- ✓Roof framing plan
- ✓Window & door schedules
- ✓1 round of revisions
- ✓Everything in Standard
- ✓3D rendering
- ✓Cross-section details
- ✓Material specifications
- ✓HOA submission package
- ✓2 rounds of revisions
- ✓Priority 5-day turnaround
After You Order
Your Addition Drawings in 3 Steps
Submit Your Project Details
Share your property address, existing floor plan (if available), and the addition scope. We assign your project coordinator within 4 business hours.
We Draft Your Drawings
Our team designs your complete addition drawing set — engineered for Bothell's building department requirements and WA CBC code. Delivered in 10 business days.
Submit to Your Building Dept
Download your complete package and submit to Building and Permit Services Division. We support plan check corrections at no extra charge.
Common Questions
Bothell Home Addition FAQs
Do I need a permit for a home addition in Bothell? +
Yes — any structural addition to your home in Bothell requires a building permit. This applies to room additions, second-story additions, sunrooms, and attached garages. You'll need permit-ready drawings before the building department will accept your application. Our packages are formatted specifically for Bothell's submittal requirements.
How much does a home addition cost in Bothell? +
Home additions in Bothell typically cost between $250.0–$350 per square foot depending on the scope, finishes, and structural complexity. A 600 sq ft addition ranges from $150,000 to $210,000. Second-story additions cost more than ground-floor extensions due to structural requirements. Our drawing packages start at $1,497 — a fraction of local architectural fees.
What drawings are required to permit a home addition in Bothell? +
Bothell's building department requires: a site plan showing the addition's footprint and setbacks, floor plans for all affected levels, all four exterior elevations, an electrical plan, and energy compliance (Title 24 in California). Structural plans stamped by a licensed engineer are required for any load-bearing elements — included in our Premium package.
How long does the permit process take for a home addition in Bothell? +
Plan check in Bothell typically takes 7 weeks for home additions. Additions with structural components may require additional review. Complete, code-compliant drawings significantly reduce correction cycles — each cycle adds 3–6 weeks. Our drawings are engineered to pass on the first submittal.
What setbacks apply to home additions in Bothell? +
Bothell enforces minimum setbacks from property lines for all additions: typically 4–5 ft side setbacks and 5 ft rear setbacks, though these vary by zoning district and lot size. Your addition must stay within the buildable envelope. Our site plan documents existing and proposed setbacks and flags any zoning variances required.
Do I need structural drawings for a home addition in Bothell? +
Yes, for most additions. Any load-bearing walls, new foundations, second-story construction, or roof structure changes require stamped structural drawings from a licensed engineer. California's CBC (California Building Code) and seismic requirements make structural plans mandatory for most addition types. Our Standard and Premium packages include stamped structural drawings.
How much do home addition drawings cost in Bothell? +
Our permit-ready home addition drawing packages for Bothell start at $1,497. Local architects and designers typically charge $3,000–$10,000+ for comparable drawing sets. Every package is engineered for WA code compliance and formatted for Bothell's building department. Turnaround is 10 business days with a 14-day money-back guarantee.
Will a home addition increase my home's value in Bothell? +
In Bothell, where median home values are approximately $900,000, a permitted home addition adds square footage that appraisers value as part of the home's gross living area. Return on investment varies by addition type — master suite additions, family room expansions, and additional bedrooms typically recoup 50–75% of project cost in appraised value in WA markets.
Can I add a second story to my home in Bothell? +
Second-story additions are permitted in most Bothell residential zones, subject to height limits and design review requirements. California generally requires ministerial permit approval, but some cities impose design compatibility or neighborhood compatibility review for second stories. Our drawings cover all levels including foundation upgrades, shear walls, and roof framing required for vertical additions.
Also Available in Bothell
Adding an ADU instead? See our ADU design service.
Next Steps
Ready to Move Forward With Your Bothell 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 and Permit Services 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
$997 – $2,997
- ✓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 and Permit Services Division. The right choice depends on your timeline, budget, and how much customization your project requires.