WDI Report Generator Calculator
Score a wood-destroying insect inspection by findings across NPMA-33 report sections — live insects, mud tubes, exit holes, frass, damage, and conducive conditions.
About this calculator
This tool turns raw WDI (wood-destroying insect) inspection counts into the structured severity score and recommendation an NPMA-33 report is built around — the standard industry inspection form, published by the National Pest Management Association and used nationwide for real-estate closings, documenting evidence of termites, carpenter ants, carpenter bees, and reinfesting wood-boring beetles. Each finding type is weighted by how urgent it is: live insects carry the heaviest weight (10 points each) since they indicate an active, ongoing infestation, mud tubes are next (8) as clear subterranean-termite evidence, damaged structural members (7) and frass deposits (6) follow, and exit/kick-out holes (5) trail slightly since they can indicate past rather than current activity. A separate, lighter-weighted conducive-conditions score (wood-soil contact, moisture, crawl-space debris) captures conditions that invite future infestation even with no current evidence. Evidence and conducive scores sum into a total severity rating capped at 100.
The recommendation level is not just a score threshold — it's rule-based: any live insects, or mud tubes co-occurring with frass, trigger "Active Infestation" regardless of the numeric score, while evidence with no live activity is scored lower as "Evidence Found," and conducive conditions alone (no direct evidence) rank lowest as advisory-only. Estimated treatment cost is a base figure by recommendation level ($1,800 active, $1,200 evidence, $400 conducive-only) plus $350 per damaged member for treatment access, while repair cost is a flat $850 per damaged member — both are ballpark planning figures, not adjusters' estimates. This tool structures and prioritizes findings for report writing; it doesn't replace the licensed inspector's on-site judgment about causation, extent, or species identification.
Inputs
Results
Severity rating (0-100)
0
Recommendation (0=Clear, 3=Active)
0
Total estimated cost ($)
$0.00
Figures current as of 2026. Source: National Pest Management Association, NPMA-33 Wood Destroying Insect Inspection Report
How to Use This Calculator
- Enter counts of insect evidence found: live insects, mud tubes, exit/kick-out holes, frass deposits, and damaged structural members.
- Enter counts of conducive conditions: wood-soil contact points and moisture problem areas, plus whether cellulose debris is present in the crawl space (0 = No, 1 = Yes).
- Review the severity rating (0-100) and recommendation level (0 = Clear, 1 = Conducive conditions, 2 = Evidence found, 3 = Active infestation).
- Check the evidence score, conducive conditions score, total findings, and finding categories affected for a breakdown of the scoring.
- Review the estimated treatment cost, estimated repair cost, and total estimated cost, along with the cost breakdown chart.
What each input means
- Live insects found
- Count of locations with live termites, beetles, or carpenter ants.
- Mud tubes found
- Number of subterranean termite shelter tubes on foundation/walls.
- Exit/kick-out holes
- Drywood termite or beetle exit holes in wood members.
- Frass deposits
- Locations with sawdust-like frass from boring insects.
- Damaged structural members
- Count of joists, studs, sills, or other members with visible damage.
- Wood-soil contact points
- Locations where wood directly contacts soil (conducive condition).
- Moisture problem areas
- Areas with standing water, plumbing leaks, or excessive moisture.
- Cellulose debris in crawl (0=No, 1=Yes)
- Wood scraps, cardboard, or form boards left in crawl space.
What each result means
- Severity rating (0-100)
- Weighted severity score. Higher = more urgent action needed.
- Recommendation (0=Clear, 3=Active)
- 0 = Clear, 1 = Conducive conditions, 2 = Evidence found, 3 = Active infestation.
- Total findings
- Sum of all evidence and conducive condition findings.
- Evidence score
- Weighted score from insect evidence findings.
- Conducive conditions score
- Weighted score from conditions favorable to pests.
- Finding categories affected
- Number of different evidence types present.
- Estimated treatment cost ($)
- Approximate treatment cost based on severity.
- Estimated repair cost ($)
- Approximate structural repair cost for damaged members.
- Total estimated cost ($)
- Combined treatment and repair cost estimate.
How this is calculated
Worked example, using the default values
- Identify Input Parameters4 parametersLive insects found = 0, Mud tubes found = 0, Exit/kick-out holes = 0, Frass deposits = 0 = 8 input(s) provided
- Calculate Severity ratingSeverity rating = min(100, totalScore)0 = 0
- Calculate RecommendationRecommendation0 = 0
- Calculate Total estimated costTotal estimated cost = round((estimatedTreatmentCost + estimatedRepairCost) * 100) / 1000 = $0
- Calculate Total findingsTotal findings = liveInsects + mudTubes + exitHoles + frassDeposits0 = 0
- Calculate Evidence scoreEvidence score = liveInsects * liveInsectWeight0 = 0
Figures and sources
- NPMA-33 Wood Destroying Insect Inspection Report — standard industry form (2026) — National Pest Management Association, NPMA-33 Wood Destroying Insect Inspection Report
Engine last updated . Checked against 2 independently-derived tests — how we verify calculators. Built by Paul Gunder, a software engineer, not a licensed financial, medical, or legal professional.
Frequently Asked Questions
Why does even one live insect finding trigger 'Active Infestation' regardless of my total severity score?
The recommendation level uses rule-based logic, not just a score threshold: if liveInsects > 0, or if mud tubes and frass deposits both appear, the level is forced to 3 (Active Infestation) no matter how low the numeric severity rating comes out. This mirrors real inspection practice — a single live termite or beetle found on site means active infestation regardless of how minor the visible damage looks. It also mirrors how the NPMA-33 report itself is structured: the standard industry WDI inspection form has a dedicated field for whether visible evidence of active infestation was observed, and that finding alone drives the report's outcome independent of how much structural damage is separately documented.
What's the difference between the severity rating and the recommendation level?
Severity rating is a numeric score (0-100, capped) built from weighted points per finding — it tells you roughly how much evidence and risk is present. Recommendation level (0-3) is a separate rule-based category — Clear, Conducive Only, Evidence Found, or Active Infestation — that can jump to 3 from a single live-insect finding even when the numeric severity score itself is still low, since one live insect only adds 10 points toward the 100-point cap.
How is the estimated repair cost calculated for damaged structural members?
Repair cost is a flat $850 per damaged member entered, completely independent of the treatment cost calculation. Treatment cost, by contrast, starts from a base figure tied to recommendation level ($1,800/$1,200/$400/$0) and adds $350 per damaged member for the extra access work treatment requires — so damaged members increase both figures, but through separate formulas.
Do conducive conditions alone — no insects or damage — ever count as 'Active Infestation'?
No. Wood-soil contact, moisture issues, and crawl-space debris only ever push the recommendation level to 1 (Conducive Conditions Only) when no insect evidence (live insects, mud tubes, exit holes, frass, or damaged members) is present at all. Active Infestation and Evidence Found both require at least one direct evidence finding — conducive conditions by themselves are treated as advisory, not urgent.
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