Data infrastructure

Powered by government and industry data

Every ADUVerify report draws from seven live data sources — five government databases and two commercial APIs. Here is exactly what we retrieve from each source, how current that data is, and where you can verify it yourself.

FEMA National Flood Hazard Layer (NFHL)

Government

What we retrieve: Flood zone designation (Zone AE, Zone X, Zone VE etc.) and SFHA (Special Flood Hazard Area) status for the property coordinates.

Data currency: Live API call at time of report generation. FEMA FIRM panels are updated on a rolling basis — typically annually for high-risk areas.

Geographic coverage: Nationwide. Available for all 58 California counties.

Verify yourself: msc.fema.gov — enter any address to view the official FIRM panel.

Note: FEMA API non-response (no data returned) is not the same as "no flood risk." When FEMA returns no data, the report displays "No SFHA designation returned" — not a confirmed clear. Verify with your local floodplain administrator for definitive status.

CAL FIRE Fire Hazard Severity Zone (FHSZ) — FRAP 2024

Government

What we retrieve: State-designated Fire Hazard Severity Zone classification (Moderate, High, Very High) and State Responsibility Area (SRA) status for the property coordinates via the CAL FIRE FRAP ArcGIS REST service.

Data currency: FRAP 2024 dataset — the most recent statewide FHSZ mapping, updated from the 2022 revision. Live API call at report generation time.

Geographic coverage: California only. FHSZ designations apply to State Responsibility Areas — not all California parcels have a state fire designation.

Verify yourself: egis.fire.ca.gov/FHSZ — official CAL FIRE FHSZ viewer.

RentCast rental market statistics (by ZIP code)

Commercial

What we retrieve: The average asking rent of active one-bedroom listings in the property's ZIP code, the lowest and highest of those listings, and how many there were.

Data currency: Live API call at report generation. RentCast calculates these statistics from active rental listings in the ZIP code.

Geographic coverage: Nationwide. The listing count varies by area — your report shows the count it used; rural areas may return few or none. With none, the report shows no rent figure; return figures need at least 3 one-bedroom listings.

Verify yourself: rentcast.io — public rental estimate tool for any US address.

The rent figure is an average of asking rents for active listings — not a projection for this property and not guaranteed rental income. Actual rent depends on unit size, condition, finishes, and local vacancy rates. Cap rate and payback projections use $250K as the build cost assumption — actual costs vary.

FCC Block API

Government

What we retrieve: County FIPS code and census block, used to confirm which county the property is in.

Data currency: 2020 census block boundaries.

Geographic coverage: Nationwide. Used for all California properties.

Verify yourself: geo.fcc.gov

Google Maps Geocoding API

Commercial

What we retrieve: Latitude and longitude coordinates, normalised address string, and place type (residential / commercial).

Data currency: Live API call at report generation.

Geographic coverage: Worldwide. Address normalisation and geocoding available for all California addresses.

Verify yourself: maps.google.com — search any address to verify coordinates.

California HCD — ADU Law Reference

Government

What we use: California Department of Housing and Community Development (HCD) ADU law interpretations — Gov. Code §66310 et seq., as amended by SB 543 and AB 1154 — encoded as the rule set applied during Maximum Unit Potential calculation.

Data currency: ADUVerify law rules are updated when California legislature enacts material changes to ADU statutes. Current rules reflect 2026 California ADU law.

Geographic coverage: California only.

Verify yourself: hcd.ca.gov/adu — official HCD ADU guidance and local ordinance database.

OpenStreetMap Nominatim

Open Source

What we retrieve: Land use classification (residential, commercial, industrial), property type confirmation, and coastal zone proximity check used in the site conditions overlay assessment.

Data currency: OpenStreetMap is updated continuously by the global contributor community. Data quality varies by area — urban California is well-maintained; rural areas may have gaps.

Geographic coverage: Worldwide.

Verify yourself: nominatim.openstreetmap.org

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All seven data sources query live APIs at the moment you order. Your report reflects data as of the generation time.

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