Full transparency — open methodology

Grading Methodology

How we calculate every grade in a ParcelScore report. Every formula, every threshold, every data source — documented for actuaries, underwriters, and anyone who needs to trust the numbers.

Last updated: March 2026 · Version 1.2

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1. Overall Grade

The overall grade is a weighted average of four core risk dimensions. Each dimension reflects a distinct insurance peril, with weights adjusted per state (e.g. flood-heavy in FL, earthquake-heavy in CA).

Weight Distribution

40%
Flood Risk
#1 insurance cost driver in FL
25%
Fire Protection
ISO class drives premium
25%
Wind & Storm
Hurricane is #1 catastrophe risk
10%
Earth Hazards
Low frequency in SE Florida
// Formula
overall = (fire * 0.25) + (flood * 0.40) + (earth * 0.10) + (wind * 0.25)

Grade Scale

GradeScore RangeInterpretation
A90 - 100Excellent — minimal risk across all factors
B+80 - 89Very good — low risk with minor exposure
B70 - 79Good — moderate risk, typical for most FL properties
B-60 - 69Fair — some elevated risk factors present
C+50 - 59Below average — multiple risk factors
C40 - 49Poor — significant risk exposure
D30 - 39High risk — major risk factors present
F0 - 29Critical — extreme risk, likely requires specialized insurance

Flood is weighted heaviest at 40% because flood is the number one insurance cost driver in Florida. According to FEMA, one inch of floodwater can cause $25,000 in damage. Florida accounts for over 35% of all NFIP claims nationally despite having only 7% of the U.S. population.

2. Fire Protection Grade

Measures how well a property is protected from fire based on proximity to hydrants, distance to fire stations, and ISO Protection Class. Components are scored only when data is available — missing data does not penalize the property.

Hydrant Distance

Max 40 points

Nearest fire hydrant by straight-line distance (Haversine formula)

DistancePointsNote
≤ 200 ft40Excellent — within direct hose lay
≤ 500 ft32Good — one connection
≤ 1,000 ft24Adequate — standard reach
≤ 2,000 ft16Distant — may require relay
> 2,000 ft0Beyond practical hydrant use
City/County ArcGIS (hydrants)

Fire Station Distance

Max 35 points

Nearest station by straight-line distance

DistancePointsNote
≤ 1.5 mi35Excellent — urban response
≤ 2.5 mi28Good — suburban response
≤ 4 mi18Adequate — typical rural
≤ 6 mi8Distant — extended response time
> 6 mi0Remote — limited fire protection
USGS National Map (fire stations)

ISO Protection Class

Max 25 points

Insurance Services Office fire protection classification (1 = best, 10 = unprotected)

ISO ClassPointsNote
Class 125Top-tier fire protection (e.g., Fort Lauderdale)
Class 2-322Excellent protection
Class 4-516Good protection
Class 6-710Average protection
Class 8+0Below average protection
ISO / Verisk
Score Normalization

The fire score is normalized to available components. If hydrant data is unavailable for a region, the property is scored on station distance + ISO class only (max 60 points scaled to 100). This prevents properties in areas without public hydrant GIS data from being unfairly penalized.

// Example: no hydrant data available
maxAvailable = station(35) + iso(25) = 60
rawScore = 28 + 25 = 53
normalizedScore = (53 / 60) * 100 = 88.3 → Grade: B+
Known Limitations
  • Hydrant data is currently available in 8 FL regions (Broward, Miami-Dade, Palm Beach, Pompano Beach, Fort Lauderdale, Hollywood, Hialeah, Coral Springs). Expanding quarterly.
  • Station data is statewide via USGS National Map but uses straight-line distance, not drive time.
  • ISO Class is looked up by jurisdiction, not by individual property split classification.

3. Flood Risk Grade

Evaluates flood exposure using FEMA flood zone designation, property elevation, and storm surge vulnerability. Starts at 100 and applies deductions for each risk factor present.

Deduction Schedule

Base score: 100. Deductions are cumulative.

Risk FactorDeductionRationale
SFHA (Special Flood Hazard Area)-40Mandatory flood insurance required; 1% annual flood probability
Coastal V Zone (VE / V)-20Wave action + velocity flooding; highest-risk coastal areas
Base Flood Zone (AE / A)-10Riverine or tidal flooding with established BFE
Shallow Flooding (AH / AO)-15Ponding or sheet flow areas; often overlooked risk
Elevation < 5 ft ASL-20Critically low; vulnerable to tidal + storm surge
Elevation < 8 ft ASL-10Low-lying; at risk from Cat 1-2 storm surge
Elevation < 12 ft ASL-5Moderate; some exposure to major storm surge
Storm Surge Cat 1-2-15Property in evacuation zone for weakest hurricanes
Storm Surge Cat 3-10Property in major hurricane surge zone
Storm Surge Cat 4-5Property in extreme hurricane surge zone
// Example: AE zone, 7ft elevation, Cat 2 surge
score = 100 - 40(SFHA) - 10(AE) - 10(elev <8ft) - 15(surge Cat 1-2) = 25 → Grade: F

Data Sources

FEMA NFHL (601K polygons)USGS 3DEP (elevation)Miami-Dade Evac Zones (storm surge)
Known Limitations
  • Elevation is queried from USGS 3DEP point elevation service (1/3 arc-second resolution, ~10m). This is not a surveyed Base Flood Elevation (BFE) and may differ from an Elevation Certificate.
  • Storm surge evacuation zones currently sourced from Miami-Dade County. Broward + Palm Beach zones planned Q2 2026.
  • FEMA flood maps may not reflect recent construction, mitigation projects, or pending LOMR/LOMA amendments.

4. Wind & Storm Grade

Assesses hurricane wind exposure based on Florida Building Code design wind speeds and High Velocity Hurricane Zone (HVHZ) designation. Starts at 100 and applies deductions.

Deduction Schedule

Base score: 100. HVHZ and wind speed deductions are cumulative.

Risk FactorDeductionRationale
HVHZ (High Velocity Hurricane Zone)-30Miami-Dade + Broward; strictest building code in U.S.
Design Wind ≥ 185 mph-25Extreme — coastal Miami-Dade
Design Wind ≥ 180 mph-20Very high — Miami-Dade / Broward coast
Design Wind ≥ 170 mph-15High — SE Florida coast
Design Wind ≥ 150 mph-10Elevated — FL Atlantic coast
Design Wind ≥ 130 mph-5Moderate — most of peninsular FL
// Example: HVHZ property in Miami-Dade, 185mph
score = 100 - 30(HVHZ) - 25(wind \u2265185) = 45 → Grade: C

Note: HVHZ designation means the property is subject to the strictest building code requirements in the United States. While this means higher construction costs, newer HVHZ-compliant structures are among the most hurricane-resistant buildings in the country. The grade reflects exposure, not building quality.

Data Sources

FL Building Code wind speed mapsHVHZ boundary (Miami-Dade + Broward)
Known Limitations
  • Wind speed is assigned at city/municipality level from FBC maps, not parcel-level ASCE 7-22 calculation.
  • Does not account for terrain exposure categories (B/C/D) or building-specific wind pressure coefficients.
  • Topographic effects and shielding from adjacent structures are not modeled.

5. Earth Hazards Grade

Evaluates geological hazards including sinkhole susceptibility and radon gas exposure. Starts at 100 and applies deductions for each hazard.

Deduction Schedule

Risk FactorDeductionRationale
Sinkhole: Very High-40Active karst geology; significant subsidence risk
Sinkhole: High-30Known karst features in area
Sinkhole: Moderate-15Some karst indicators present
Sinkhole: Low-5Minimal karst risk
Radon Zone 1 (highest)-20>4 pCi/L predicted average indoor level
Radon Zone 2-102-4 pCi/L predicted average indoor level
// Example: SE Florida property (typical)
score = 100 - 0(sinkhole: Very Low) - 0(radon: Zone 3) = 100 → Grade: A
// Note: SE FL is generally Very Low sinkhole risk and Radon Zone 3 (lowest)

Data Sources

Florida Geological Survey (sinkhole)EPA (radon zones)
Known Limitations
  • Sinkhole susceptibility is based on FGS regional mapping, not site-specific geotechnical investigation.
  • Radon zones are EPA county-level designations, not building-level measurements. Actual radon levels vary by structure.

6. Crime Grade

Benchmarks the property's city crime rate against the Florida state average using FDLE Uniform Crime Report data. This grade does not factor into the overall property grade — it is reported separately.

Benchmark: Florida State Average

State average crime rate: 34.9 per 1,000 residents (FDLE UCR 2023). Includes: murder, rape, robbery, aggravated assault, burglary, larceny, motor vehicle theft.

GradeRate Rangevs. State AverageExample Cities
A< 21 per 1KBelow 60%Weston, Coral Springs
B21 - 31 per 1K60 - 90%Pembroke Pines, Miramar
C31 - 42 per 1K90 - 120%Fort Lauderdale, Tampa
D42 - 56 per 1K120 - 160%Miami, Orlando
F> 56 per 1KOver 160%Miami Beach, Opa-Locka

Data Sources

FDLE Uniform Crime Report 2023

Coverage: 37 major Florida cities with published UCR data.

Known Limitations
  • Crime data is city-level aggregate from FDLE, not neighborhood or block-level. A property in a safe neighborhood within a high-crime city will receive the city-wide grade.
  • Unincorporated areas use county-level rates, which may be less representative.
  • UCR data lags by approximately 12 months from the reporting period.

7. Data Sources

Every data point in a ParcelScore report comes from a government source. We do not estimate, model, or infer values. Below is a complete inventory of our data sources.

LayerSourceRecordsUpdate Freq.Coverage
Property RecordsFL Dept of Revenue (FDOR)10.8M parcelsAnnualAll 67 FL counties
Flood ZonesFEMA NFHL601K polygonsAs amendedAll 67 FL counties
Building PermitsCounty Building Depts342K permitsMonthlyBroward, Miami-Dade, Palm Beach
Fire HydrantsCity/County ArcGIS142K hydrantsQuarterly8 FL regions
Fire StationsUSGS National Map1,747 stationsAnnualStatewide
NFIP ClaimsFEMA OpenFEMA1,362 ZIP codesMonthlyStatewide
School GradesFL DOE (FLDOE)2,953 schoolsAnnualStatewide
Crime RatesFDLE UCR 202337 citiesAnnual37 major FL cities
EPA Hazard SitesEPA TRI / Superfund1,410 facilitiesAnnualStatewide
ElevationUSGS 3DEPLive APIReal-timeStatewide
Wind SpeedFL Building CodeBy cityCode cycle (~3yr)Statewide
HVHZ BoundaryFL Building Commission2 countiesCode cycleMiami-Dade + Broward
Sinkhole RiskFL Geological SurveyBy countyPeriodicStatewide
Radon ZonesEPABy countyStatic (1993)Statewide
Storm SurgeCounty Emergency Mgmt2,147 zonesAnnualMiami-Dade (expanding)
Roof AgeDerived from permits32K propertiesWith permitsBroward, MDC, PBC

8. Limitations & Disclaimers

Transparency is core to our methodology. We want you to know exactly what a ParcelScore report can and cannot tell you.

  • Informational Only: ParcelScore reports are for informational purposes only. They are not a substitute for a professional property inspection, appraisal, insurance underwriting assessment, or environmental site assessment.
  • Government Data Accuracy: All data is sourced from government agencies. These sources may contain errors, be outdated, or not reflect recent changes (construction, mitigation, FEMA map amendments, etc.).
  • Relative Risk, Not Absolute Safety: Grades reflect relative risk compared to other Florida properties. An "A" grade does not mean a property is immune to a given hazard — it means the measurable risk factors are lower than most properties.
  • Missing Data Handling: When data is unavailable for a specific layer (e.g., no hydrant data in a region), the missing component is excluded from scoring rather than penalized. Missing values are displayed as "—" in reports.
  • Crime Data Granularity: Crime grades are based on city-level aggregate data from FDLE, not neighborhood or block-level statistics. Significant variation exists within cities.
  • School Grades: School grades are from the FL Department of Education. Not all areas have attendance-zone-specific mapping; some use district-wide averages.
  • Elevation vs. Surveyed BFE: Elevation data comes from USGS 3DEP (~10m resolution). This is not a surveyed Base Flood Elevation and should not be used in lieu of an Elevation Certificate for insurance rating.
  • No Guarantee of Insurance Outcome: ParcelScore grades do not predict insurance premiums, coverage availability, or claim outcomes. Insurance underwriting involves additional factors beyond the scope of this report.

9. How We Compare

We believe in honest positioning. Here's how ParcelScore compares to HazardHub, the industry-standard property risk platform acquired by Guidewire.

CapabilityParcelScoreHazardHub
Core data sourcesFEMA, USGS, EPA, ISOFEMA, USGS, EPA, ISO
Flood zones (FEMA NFHL)YesYes
Fire protection (ISO, hydrants)YesYes
Wind / hurricane riskCity-level FBCParcel-level ASCE 7-22
Wildfire riskNot yetYes
Hail riskNot yetYes
Lightning riskNot yetYes
Soil liquefactionNot yetYes
Building permitsYes (342K)No
School gradesYes (2,953)No
Crime statisticsYes (37 cities)No
NFIP claims by ZIPYesLimited
WhatsApp deliveryYes (core channel)No
API accessYes (REST)Yes (REST)
Coverage28 states (expanding)All U.S.
PricingFrom $99/mo$50K-200K/yr enterprise

Our position: HazardHub is the gold standard for enterprise property risk data with nationwide coverage and deeper peril layers (wildfire, hail, lightning). ParcelScore covers 28 states with 143M+ records and unique layers (building permits, school grades, crime stats, NFIP claims history) and dramatically lower price points. We serve insurance agents, real estate professionals, and property owners who need property-specific intelligence without enterprise contracts.

See it in action

Send any US address to our WhatsApp or search on the web — graded exactly as described above.