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COST_SPEC / BOTHELL

Bothell ADU Cost: What Homeowners Should Budget For

Real Bothell, WA pricing for detached and attached ADUs across six lot-size bands. Numbers reflect current bids and recent projects, not internet averages.

Last verified 2026-05-15 · Page in progress — not yet indexed

COST_TABLE / PLANNING ESTIMATES

We're verifying Bothell's cost data this quarter. Contact us for a current estimate on your specific lot.

Numbers above are planning estimates from current bids and recent Golden State ADU projects on Puget Sound lots — they are not city-published fees. Verify current Bothell permit and utility fees against the official sources linked below before committing a budget.

FAQ / BOTHELL COST

Bothell ADU pricing questions

  • What does a typical detached ADU cost in Bothell?

    Bothell all-in detached ADU pricing varies by lot size and site complexity. Send your address for a same-week range.

    Go deeper: Bothell ADU cost breakdown

  • What's included in the Bothell construction line?

    Construction in Bothell is priced separately from design, permits, and site work so each line is visible.

    Go deeper: Bothell ADU overview

CITY_DOSSIER / BOTHELL· 47.7623°N 122.2054°W

Built in Bothell — what we know that the spec sheet won't tell you.

A live dossier from our field PMs: the permit counter, the soils, the bylaw that just changed, and the streets where ADUs are already cash-flowing.

Map · King & Snohomish CountiesOpen ↗
Bothell
Drive-time from yard · ≈ 24 min via I-405© OpenStreetMap contributors
Population48,915
Median lot7,900 sq ft
ADU permits / yr47 (2024)
Build cost band$330–370 / sq ft
Right now in Bothell
Air quality · US AQI
Source · Google Maps PlatformAffects pour windows + finish schedule
LIVE_INTEL / BOTHELL · 6 SIGNALS
Pour-feasibility · todayLoading
/ 100 · Awaiting feed
  • Weather feed loading
Derived live · Bothell weather + AQI
Sun rhythm · BothellDaylight
5:25 AM
9:06 PM
15h 41m daylight
Golden hour · 8:19 PM
98% of June peak
NOAA solar formulas · computed
Moon · cure-week planner
Loading

We track lunar weeks for slab pours — clear nights drop ambient temperature faster, which slows surface curing. Schedule wet slabs midweek under waxing light.

Conway approx · computed
Seismic · 24h within 60 miLoading
USGS earthquake.usgs.gov
On-site clock · Bothell
—:—
· Pacific

Loading. Our standard crew window is 7:00–17:00 weekdays — noise ordinances in most Puget Sound cities allow exterior power tools only inside that band.

America/Los_Angeles · live
Build-rules pulseWithin window
7:00–17:00
Power-tool window · Mon–Fri
ADU permits YTD pace

Sunday exterior work is restricted in most Puget Sound jurisdictions. We sequence interior trades around it.

Bothell municipal code · annualized
SPEC_02 / CITY_INTEL

Environmental & locational intelligence

03 / SOLAR_POTENTIAL

Rooftop solar at this address

04 / POLLEN_FORECAST

Tree · Grass · Weed (3-day)

05 / WALK_SCORE

0.5-mile amenity density

06 / NWS_ALERTS

Active NWS weather alerts

LOCATIONAL_INTEL / BOTHELL
Drive times from BothellLoading

Calculating live drive times to four metro anchors…

Real commute time matters for ADU rent comps — and for our crews. We keep installs within a 60-minute radius of our Puget Sound yard.

Data provenance

Drive times pulled live from the Google Routes API (traffic-aware matrix). Each request is timestamped so you can see exactly when the numbers were last refreshed — no stale brochure data.

Google Routes API · traffic-aware
Street view · BothellLive imagery
Recent Google Street View imagery centered near Bothell

Lot context matters as much as zoning. We pre-screen access, slope, and tree canopy from imagery before scheduling the site visit.

Google Street View · proxied
Tidal window · BothellLoading

Waterfront lots: shoreline excavation and barge access windows depend on these. We schedule pours away from extreme low tides when the soils dry unevenly.

NOAA · — mi away
Recent permits · BothellLoading

Open-data signal of nearby construction velocity — useful for ADU comps and for anticipating examiner workload.

data.seattle.gov · ~3 mi radius
Permit counter · Bothell
Bothell Community Development
9654 NE 182nd St, Bothell 98011
Mon–Fri 8a–5p · in-person intake limited
Local zoning quirk

Lots straddle King & Snohomish lines — fees and tree code differ across the county line on the same street.

Sourced from Golden State ADU field PMs · WA Lic. GOLDESA747LZ
Best build window
Late April → October

Bar shows pour-friendly months · dot marks the current month.

  • Seismic
    SDC D · north of Seattle Fault, lower direct exposure
  • Soil
    Till uplands; peat near the Sammamish River
  • Climate
    ≈39″ rain · convergence zone catches stacked showers
  • Topography
    Plateau flat; canyon edges near North Creek steep
  • HOA prevalence
    ≈ 22%
Transit signal
ST Express 522 + planned Stride S3 BRT (2028)

Station-area lots earn the largest rent premium in this market.

School signal
Northshore School District

Rental yield estimate: $2,500–3,200 / mo · UW Bothell demand drives small DADUs

Local incentive

Northshore housing-stability ADU rental incentive (10-yr lease commit)

Hidden gem

UW Bothell-adjacent DADUs lease faster than any other student-housing alt nearby.

Build cost · Bothell vs Puget Sound
+$25 vs regional median
$250 / sqftBothell$350$425 / sqft
Other cities we hold a permit history in
COST_BOTHELL / FULL

Get a full Bothell ADU cost breakdown — line by line, not a range.

Bothell's permit fees, soils and design review costs swing 20%+ between blocks. We'll send the breakdown for your specific address, not a citywide average.

  • Bothell permit + impact fees included
  • Allowance schedule for finishes attached
  • Free 1-pager, no sales call required
Replies within 1 business day
WA Lic. GOLDESA747LZBuilding since 2012
Direct line · Golden State ADU(425) 642-4142

We reply within 1 business day. No spam, ever.

◇ No sales script · No spam · Your details stay with our team