How Our Fire Risk Assessment Works
Understand the science behind our professional wildfire risk scoring system, based on proven fire behavior research and industry standards.
Assessment Overview
Our Fire Risk Assessment is a comprehensive 18-question evaluation designed to measure your property's vulnerability to wildfire. Unlike simple checklists, our tool uses weighted scoring algorithms and scientific fire behavior models to provide an accurate risk percentage.
Research from the Insurance Institute for Business & Home Safety shows that home survival during wildfire depends more on the immediate surroundings than firefighter intervention. Understanding your specific vulnerabilities allows you to take targeted action that significantly reduces risk.
What We Evaluate
The assessment analyzes your property across six critical categories, each weighted according to its impact on fire survivability:
- Zone 1 (0-5 feet) โ The most critical area directly against your home
- Zone 2 (5-30 feet) โ The lean, clean, and green zone
- Zone 3 (30-100 feet) โ Extended defensible space
- Structure โ Roof, vents, siding, windows, and deck vulnerabilities
- Access โ Emergency vehicle access and address visibility
- Terrain โ Slope, aspect, and topographical features
Assessment Duration
The quiz takes approximately 3-4 minutes to complete. Each question includes helpful descriptions to ensure accurate answers, even if you're not familiar with fire mitigation terminology.
The 3 Defensible Space Zones
Defensible space is the buffer zone between your home and the surrounding wildland area. The concept divides the area around structures into three concentric zones, each with specific management requirements.
Post-fire studies consistently show that homes with properly maintained defensible space are 2-4 times more likely to survive wildfire than those without. Zone 1 (0-5 feet) is particularly criticalโembers landing in combustible materials here cause the majority of home ignitions.
This is the most critical area for home survival. The goal is to create an ember-resistant zone with no combustible materials that can ignite and spread fire to your structure.
- No combustible mulch (use gravel, stone, or bare soil)
- No dead vegetation or accumulated debris
- No firewood, propane tanks, or combustible storage
- Clear gutters of pine needles and leaves
- No plants touching exterior walls or windows
This zone focuses on removing ladder fuels and creating spacing that prevents fire from climbing into tree canopies or spreading rapidly toward your home.
- Tree crowns spaced at least 10 feet apart
- Lower tree branches pruned 6-10 feet from ground
- Shrubs separated from trees to break ladder fuels
- Remove dead plants, fallen branches, and dry grass
- Lawn maintained at 4 inches or less
The goal here is to reduce fire intensity as it approaches your property by creating discontinuity in vegetation that slows or stops fire spread.
- Remove dead trees, especially those leaning toward home
- Thin dense vegetation to reduce fuel continuity
- Create fuel breaks along driveways and slopes
- Remove small conifers growing between larger trees
- Stack firewood at outer edge, uphill from home
The 6 Assessment Categories
Our assessment evaluates your property across six weighted categories. The weights reflect each category's relative importance to overall fire survivability, based on post-fire research and NFPA guidelines.
| Category | Weight | Questions | What We Assess |
|---|---|---|---|
| Zone 1 (0-5 ft) | 25% | 3 | Combustibles, vegetation, debris accumulation |
| Zone 2 (5-30 ft) | 20% | 3 | Ladder fuels, crown spacing, vegetation type |
| Zone 3 (30-100 ft) | 10% | 2 | Vegetation density, dead/stressed trees |
| Structure | 25% | 5 | Roof, vents, siding, deck, windows |
| Access | 10% | 2 | Address visibility, driveway access |
| Terrain | 10% | 3 | Slope, aspect, terrain features |
Zone 1 and Structure each carry 25% weight because research shows these are the two most critical factors in home ignition. Embers landing in Zone 1 combustibles cause most wildfire home losses, while structural vulnerabilities (especially roofs and vents) determine whether those embers ignite your home.
Question Point Values
Each question has 4 answer options with point values ranging from 0 (optimal/lowest risk) to the maximum for that question. The maximum points vary by question based on risk severity:
- 0 points โ Optimal condition, meets or exceeds guidelines
- Low points โ Minor issues, low additional risk
- Medium points โ Moderate issues requiring attention
- High points โ Significant vulnerabilities, priority action needed
Scoring Formulas & Math
Our scoring system uses a multi-step calculation that first computes a weighted base score, then applies terrain modifiers based on peer-reviewed fire behavior research.
Step 1: Calculate Category Scores
For each category, we calculate what percentage of maximum possible points you scored:
Step 2: Calculate Weighted Base Score
We multiply each category score by its weight, then sum them:
Step 3: Apply Terrain Modifiers
The base score is then modified by slope and aspect factors. We use square roots to prevent extreme values while still accounting for terrain impact:
Final scores are capped at 100%. Even if modifiers would push the score higher, we cap at 100% to maintain interpretability. Scores approaching 100% indicate extreme risk requiring immediate professional assessment.
Terrain Modifiers Explained
Terrain is one of the most significant factors in fire behavior. Two properties with identical vegetation can have dramatically different risk levels based on slope and aspect alone.
Slope: McArthur's Rule
Our slope calculations are based on McArthur's fire spread research, which found that fire spread rate approximately doubles for every 10 degrees of slope increase. This is because:
- Flames lean closer to uphill fuels, preheating them faster
- Convective heat rises along the slope, drying vegetation above
- Fires create their own updraft, accelerating spread
Aspect: Sun Exposure Impact
Aspect refers to the compass direction a slope faces. In Colorado's Northern Hemisphere, south-facing slopes receive the most direct sunlight, resulting in:
- Higher temperatures and lower humidity
- Drier vegetation with lower moisture content
- Earlier spring snowmelt and longer fire season
- More frequent afternoon heating and upslope winds
South and southwest-facing slopes on Colorado's Front Range are particularly vulnerable during our typical afternoon wind pattern. The combination of afternoon sun, upslope winds, and dry conditions creates optimal fire spread conditions.
Understanding Risk Levels
Your final percentage score translates to one of five risk levels. Each level indicates both the urgency of action needed and the type of interventions that will be most effective.
What Each Level Means
Low Risk (0-15%)
Your property demonstrates excellent wildfire preparedness. Defensible space is well-maintained, structural vulnerabilities are addressed, and terrain factors are either favorable or well-mitigated. Continue annual maintenance and stay vigilant during fire season.
Moderate Risk (16-35%)
Your property has a solid foundation but some areas need attention. Typically this means minor vegetation management issues or one structural vulnerability. Addressing these items before fire season will significantly improve your resilience.
High Risk (36-55%)
Multiple vulnerabilities exist that could contribute to home ignition during a wildfire. This level often indicates either Zone 1 issues, structural concerns, or both. We recommend a professional assessment to prioritize mitigation work.
Very High Risk (56-75%)
Your property has significant vulnerabilities across multiple categories. Fire reaching your property under current conditions would likely result in structure ignition. Immediate action is strongly recommended, ideally before peak fire season.
Extreme Risk (76-100%)
Critical fire risk with multiple severe vulnerabilities. Properties at this level typically have both defensible space issues and structural vulnerabilities compounded by challenging terrain. Professional on-site assessment is essential to develop a comprehensive mitigation plan.
Cost Estimation Method
Our assessment provides estimated mitigation costs based on your specific vulnerabilities. These estimates are derived from typical project costs in the Colorado Front Range market and are intended as a planning guide, not a quote.
The costs shown below are approximate ranges for planning purposes only. Every property is unique, and actual costs depend on many factors including property size, vegetation density, terrain difficulty, and accessibility.
For accurate pricing, exclusive discounts, and seasonal deals โ contact us for a FREE on-site assessment. We often offer package discounts for multiple services!
How Costs Are Calculated
The assessment tracks which services you likely need based on your answers. If you indicated risk factors in a particular area, the corresponding service is added to your estimate:
*Approximate ranges only. Actual costs vary by property. Contact us for accurate quotes.
๐ Get Your Real Quote + Exclusive Discounts
We offer package deals, seasonal discounts, and HOA partnership rates. Contact us for a free on-site assessment and personalized quote.
Cost-Benefit Perspective
While mitigation costs may seem significant, consider the alternatives:
- Average Colorado home rebuild cost: $300,000 - $500,000+
- Insurance deductibles: Often $10,000 - $50,000 for fire claims
- Potential insurance premium reduction: 5-15% with documented mitigation
- Increased property value: Fire-adapted landscapes are increasingly valued
What To Do Next
Understanding your risk is the first step. Here's how to move from assessment to action:
1. Review Your Results Carefully
Your results include a category breakdown showing where your highest vulnerabilities lie. Focus first on categories with the highest scores, especially Zone 1 and Structure if they're elevated.
2. Prioritize by Impact
Not all improvements are equal. Generally, prioritize in this order:
- Zone 1 (0-5 ft) โ Highest impact, often lowest cost
- Structural vulnerabilities โ Especially roof and vents
- Zone 2 ladder fuels โ Prevents fire from reaching canopy
- Zone 3 thinning โ Reduces intensity of approaching fire
3. Schedule Professional Assessment
While our online tool provides valuable insights, an on-site assessment by ISA Certified Arborists can identify issues not captured by questions, provide accurate cost estimates, and develop a prioritized work plan.
4. Consider Timing
Colorado's fire season typically runs May through October, with peak risk in June-July. Ideally, complete major mitigation work before fire season. However, any improvement is valuableโdon't delay action just because fire season has started.
5. Maintain Annually
Fire mitigation isn't one-and-done. Vegetation regrows, debris accumulates, and conditions change. Plan for annual maintenance and reassessment, typically in early spring before fire season.
Research Sources & References
Our fire risk assessment methodology is built on peer-reviewed research and guidelines from leading fire science organizations. Below are the primary sources that inform our scoring system:
National Fire Protection Association (NFPA)
Firewise USAยฎ program guidelines, Home Ignition Zone research, and NFPA 1144 standards for wildland fire protection.
Visit NFPA Firewise USAยฎ โColorado State Forest Service (CSFS)
Colorado-specific defensible space guidelines, forest health resources, and wildfire risk assessment protocols.
Visit CSFS Wildfire Mitigation โUSDA Forest Service
Fire behavior research, home destruction analysis, and national wildfire coordination standards.
Visit USDA Fire Management โInsurance Institute for Business & Home Safety (IBHS)
Home ignition research, building material testing, and Wildfire Prepared Home certification standards.
Visit IBHS Wildfire Research โMcArthur Fire Behavior Research
Foundational research on slope-fire spread relationships. The formula ฯ = 2^(ฮธ/10) forms the basis of our terrain modifiers.
View CSIRO Research โFEMA & Marshall Fire Report
Post-fire analysis of the 2021 Marshall Fire, including structural vulnerability findings and mitigation recommendations.
Visit FEMA Wildfire Resources โFirst Street Foundation
Fire risk modeling methodology and property-level fire factor scoring system used nationwide.
Visit First Street Fire Factor โNational Wildfire Coordinating Group (NWCG)
Interagency fire training standards including S-290 Intermediate Wildland Fire Behavior course materials.
Visit NWCG Training โReady to Assess Your Risk?
Take our free 3-minute assessment to get your personalized fire risk score, category breakdown, and estimated mitigation costs.