How Building Scores Work
SeattleSeattle uses our sophisticated 18-category scoring system with time decay, building fingerprints, and anti-clustering features. Every building gets a unique score.
π― Scoring Philosophy
"Buildings should rarely have the same score, and location matters."
No More 100.0 Scores
Max score is 99.5. Building fingerprints ensure even top buildings have different scores.
Recent Issues Matter More
Time decay: violations from 5+ years ago barely count. Last 6 months = full weight.
The Basics
Every Seattle building receives a 0-99.5 score calculated from 18 weighted categories. We analyze:
- β232,000+ code violations from Seattle SDCI with time decay
- βService requests from Seattle's 311 equivalent system
- β186,000+ building permits showing investment patterns
- βKing County Assessor data β views, hazards, sales, noise, quality ratings
- βSeismic and environmental hazards β earthquake risk, landslides, flood zones
18 Weighted Categories
Each building is scored across 18 dimensions. Total weight: ~24.4. Higher weight = more impact on final score.
Safety
3.0ΓFire safety, structural violations, and hazardous conditions
Maintenance
2.5ΓCode violations with time decay - recent issues matter more
Track Record
2.5ΓOpen violations, total history, data confidence assessment
Seismic Risk
2.0ΓSeattle-specific: seismic hazard, landslide risk, pre-code buildings
Pest
2.0ΓRodent, pest, and bed bug violations
Environmental
2.0ΓFlood zones, steep slopes, erosion, wetlands
Responsiveness
1.5ΓHow quickly violations get resolved
Service Requests
1.5Γ311-equivalent complaints from residents
Recurring Issues
1.5ΓSame violations happening repeatedly at same address
Building Quality
1.2ΓCondition and quality ratings from King County Assessor
Elevator
1.2ΓElevator issues in high-rise buildings
Noise
1.0ΓTraffic and airport noise levels from assessor data
Transit
0.8ΓLight Rail proximity (19 stations)
Permits
0.8ΓRecent permit investment and maintenance activity
Views
0.5ΓMt. Rainier, Olympics, Cascades, water views (bonus!)
Waterfront
0.5ΓWaterfront property bonus
Parks
0.3ΓAdjacent to greenbelt or major parks
Age Factor
0.3ΓBuilding age considerations and code compliance era
The Algorithm (7 Steps)
Here's exactly how we calculate the final score:
Weighted Average
final_score = Ξ£(category Γ weight) Γ· ~24.418 categories scored 0-100, each multiplied by weight. Total weight ~24.4
Catastrophic Caps
if violations > 200 or open > 30 β max 25Safety backstops: 200+ violations caps at 25, 100+ caps at 35
Differentiation Adjustment
score += diff_bonus - diff_penalty100-yr old building with 0 violations gets bonus. New 4-unit building gets penalty.
Max Score Cap
score = min(score, 99.5)No building can score 100. New buildings capped lower. Zero violations? Data skepticism.
Building Fingerprint
score += hash(parcel, year, units) β Β±0.3Unique micro-adjustment ensures no two buildings get exactly the same score.
Livability Adjustment
score += neighborhood_livability (-3 to +3)Capitol Hill +3.0, SODO -1.5. Location matters for quality of life.
Score Compression
if score > 90: compress(90-105 β 90-99.5)Prevents clustering at the top. 15 points above 90 compress to 9.5 points.
Time Decay
Recent violations matter more. A violation from 2019 barely affects your score today. Open violations always count at full weight.
| Period | Multiplier | Impact |
|---|---|---|
| Last 6 months | 1.0Γ | Full impact |
| 6-12 months | 0.85Γ | Slight decay |
| 1-2 years | 0.6Γ | Moderate decay |
| 2-3 years | 0.35Γ | Significant decay |
| 3-5 years | 0.15Γ | Heavy decay |
| 5+ years | 0.03Γ | Minimal impact |
Neighborhood Livability
Location matters! Walkable, transit-rich neighborhoods get bonuses. Industrial areas get penalties.
| Neighborhood | Adjustment | Tier |
|---|---|---|
| Capitol Hill | +3.0 | Top tier |
| Queen Anne, Fremont | +2.7 to +2.85 | Premium |
| Ballard, Green Lake | +2.4 | Excellent |
| University District | +1.8 | Solid |
| Downtown, Belltown | +1.2 to +1.35 | Urban core |
| Rainier Beach | -0.15 | Below average |
| SODO, Industrial | -1.5 to -2.0 | Not residential |
Seattle's Unique Data
Seattle has the richest dataset of any city we cover, thanks to King County Assessor:
Mountain & Water Views
Properties rated 0-4 for Mt. Rainier, Olympic, Cascade, Puget Sound, and Lake Washington views. Adds up to +25 points!
Seismic Risk Assessment
Seismic hazard, landslide risk, steep slopes flagged. Pre-1970 buildings penalized for older seismic codes.
Waterfront Properties
1,800+ waterfront properties identified with footage measurements - premium factor in scoring
Environmental Hazards
Flood zones, landslides, steep slopes, erosion, and wetlands factored into environmental score
Sales History
89% of buildings have complete sales history from King County records
Light Rail Access
Distance to all 19 Link Light Rail stations - closer is better!
Noise Assessment
Traffic noise and airport noise (SeaTac flight path) from assessor data affects score
Building Quality Ratings
Condition and quality ratings direct from King County Assessor
Anti-Clustering Features
We use several techniques to ensure buildings don't cluster at the same score:
Hash of parcel number, year built, and units creates unique Β±0.3 adjustment
Old/large buildings with clean records get bonus (harder to maintain = more impressive)
New/small buildings with perfect records get penalty (easier to maintain = less impressive)
Old/large buildings with zero violations? Suspicious. Apply skepticism penalty.
Scores 90-105 compressed to 90-99.5. Creates spread at the top.
Letter Grades
Violation Impact by Category
| Category | Examples | Severity | Weight |
|---|---|---|---|
| Fire Safety | Smoke detectors, fire exits, extinguishers | Critical | 10Γ |
| Structural | Foundation, walls, roof, unsafe conditions | Critical | 12Γ |
| Plumbing | Leaks, drainage, water heater issues | Moderate | 5Γ |
| Electrical | Wiring, outlets, lighting, panels | Moderate | 5Γ |
| Heat/Utilities | No heat, broken furnace, utility issues | High | 6Γ |
| Pests | Rodents, insects, bed bugs | Moderate | 10Γ |
| General Maintenance | Paint, flooring, fixtures, appliances | Low | 2Γ |
Seattle Tenant Protections
While Washington state prohibits rent control, Seattle has strong tenant protections:
- π RRIO β All rentals must be registered and inspected for safety
- βοΈJust Cause Eviction β Landlords can only evict for specific legal reasons
- πFirst-in-Time Rule β Must offer units to qualified applicants in order
- π°21-Day Deposit Return β WA law requires deposit return within 21 days
Data Sources
- πKing County Assessor β Property records, views, hazards, sales history (~733K records)
- ποΈSeattle SDCI β Code violations (~232K) and building permits (~186K)
- πSeattle Customer Service Bureau β Service requests (311 equivalent)
- πSound Transit β Link Light Rail station locations (19 stations)
Data is updated regularly. Scoring algorithm: scoring_sophisticated_sea.py
Frequently Asked Questions
Why can't any building score 100?
We cap scores at 99.5 and use building fingerprints to ensure every building has a unique score. This prevents clustering and makes rankings meaningful. A 100-year-old, 50-unit building with zero violations is more impressive than a 5-year-old, 4-unit building with zero violations.
Why does my building have a low score?
Low scores typically indicate recent violations, unresolved issues, or environmental hazards (seismic risk, flood zone). Check the building's detail page to see specific factors. Scores can improve as violations get resolved and time passes.
Do views and waterfront really affect scores?
Yes, but with low weight (0.5Γ). A Mt. Rainier view can add up to +25 points to the views category, but that category is only 2% of the total score. Safety and maintenance matter far more.
How does seismic risk affect scores?
Buildings in seismic hazard zones, landslide areas, or on steep slopes get penalties. Pre-1970 buildings (built before modern seismic codes) get additional penalties. This reflects real risk in earthquake-prone Seattle.
What does RRIO mean for scores?
Seattle's Rental Registration and Inspection Ordinance requires safety inspections. Violations found during RRIO inspections are included in our scoring. Buildings that consistently pass RRIO inspections tend to have higher scores.