$3,388,000
181-179 W Duane Ave, Sunnyvale 94085
AddressIntel AI Briefing
With this home built in 2026, a teardown is out of the question; the optimal play is stealth density: primary + ADU + JADU to incrementally add value. However, development pathways are severely restricted by liquefaction hazards and a modest ADU feasibility score of 52.
Property Permit History
Recent Neighborhood Remodeling (Sunnyvale)
Parcel & Zoning Info
ADU Potential
Flag / irregular · Corner lot · ~77 ft frontage × 110 ft deep, a tucked-away rear unit is very private; access is typically via the pole driveway. A second street frontage lets an ADU take its own entrance and address.
Screening heuristic based on lot size, existing coverage, lot orientation, and hazard overlays. CA ADU law is ministerial statewide; verify max size, setbacks, and JADU owner-occupancy with the local planning dept.
Redevelopment Potential
Existing home already uses most of the allowable floor area, little expansion headroom. Zoning allows roughly 2,156 sqft of gross floor area on this lot.
Screening estimate comparing existing living area to the city's single-family floor-area limit. FAR rule curated from current municipal code. Source: Sunnyvale Muni Code Ch. 19.32, Table 19.32.020 (as of 2026-06-30). Verify FAR, coverage, setbacks, and height with the local planning dept.
Hazard Snapshot
Flood Zone
Fire Severity
Liquefaction
Fault Zone
Not a substitute for a Natural Hazard Disclosure (NHD) report. Zones reflect available GIS data and may not cover all localities. Liquefaction and fault flags: modified from California Geological Survey, Web Service of Official Maps of Alquist-Priolo Earthquake Fault Zones and Web Service of Official Maps of Seismic Hazard Zones (2025).
Nearby Public Schools
Bishop Elementary
Sunnyvale
Columbia Middle
Sunnyvale
Mission Early College High
Santa Clara Unified
School boundaries are subject to change. Nearest school distance does not guarantee enrollment eligibility. Check with the local district. Data provided by CDE.
Proprietary Intelligence
Market Heat Index
66/100
Based on recent sales velocity and local demand in 94085.
Flippability Score
5/100
Measures neighborhood renovation density vs. recent permits on this property.
Bidding War Prob.
30%
Likelihood of multiple offers based on local list-to-sale ratios and DOM.
Proforma ROI Calculator
Back-of-the-napkin deal analysis across development strategies.
Zoning allows roughly 2,156 sqft here, less than the 2,754 sqft standing today, so a compliant rebuild would be smaller than the existing house. We don't quote a return on this one. Demolishing generally forfeits the existing non-conforming floor area, so treat it as a remodel or check the local code for what it lets you rebuild.
Median of 9 recent single-family sales in Sunnyvale (94085): $1,242/sqft, plus 5% because new houses sold at a median 1.07x their comps across 239 real rebuilds. Sized within 25% of the 2,800 sqft build, because smaller houses sell for more per foot and pricing a rebuild off them overstates resale.
Commission, transfer tax and closing. Deducted from resale before profit, so the ROI below is net of the exit rather than gross.
Interest on the purchase price for the whole project plus half the build budget, since construction draws ramp up. The default is 7% over 33 months, the median purchase-to-sale time of 239 real Peninsula and South Bay rebuilds. Set the rate to 0 for a cash purchase, or use your own lender's terms.
Projected Profit
Warning: Project is mathematically underwater.
Recent Comparables (Sunnyvale 94085)
Sized to the modelled 2,800 sqft build: sales within 25% of it. Smaller houses sell for more per foot, so pricing a rebuild off them overstates resale.