How the PermitFocus Growth Score works
Every US county on PermitFocus gets a single 0-100 Growth Score. It's our proprietary methodology — six factors blended into one rating, calibrated by our team based on deep market knowledge. This page tells you exactly what goes in and how.
The six factors
Every county's score is a weighted average of six independent factors. Each is normalized to 0-100 first, then combined. Click any county on PermitFocus to see the per-factor breakdown live — we don't hide the math.
How many new single-family and 1-4-unit residential permits the county pulled in the last 12 months. Log-scaled so a small market with 400 starts isn't treated as "basically zero" — it's treated as small but real.
Year-over-year change in permit volume. A county pulling more permits this year than last earns a high trajectory score; one shrinking earns a low one. Captures whether the market is accelerating or decelerating.
How steady the permit flow is month to month. Volatile counties (boom-then-quiet cycles) earn lower consistency scores than counties with predictable activity. Lumber yards and truss plants prefer predictable demand.
3-year compound annual growth rate of county population. New construction follows population growth. A county with 3%/yr CAGR is fundamentally a stronger market than one with 0.2%/yr.
Whether the county sits in a major metropolitan corridor (tier 0), an exurban or minor MSA (tier 1), or rural (tier 2). Reflects the infrastructure-driven advantage a county gets from being on a major growth axis. Currently classified for Florida; nationwide MSA-tier rollout is in development.
How much future housing is approved but not yet built — measured via recorded subdivision plats. A county with 5,000 platted lots not yet permitted is a market with locked-in future volume.
How the score is computed
For each factor, the raw input value is normalized to a 0-100 sub-score. The six sub-scores are then weighted-averaged into a single 0-100 final score. When a factor's data isn't available for a county, the remaining weights redistribute proportionally — no county is penalized for missing one data source.
What's not in the score (and why)
Some things you might expect, deliberately left out:
- Median home price. Useful for resale-market intelligence; not predictive of new-construction permit volume. We track it on county detail pages but don't score against it.
- Multi-family / apartment permits. Excluded across the board — PermitFocus is single-family and townhome focused because that's where LBM, truss, roofing, HVAC, and trade contractors actually have addressable revenue.
- Builder concentration / Herfindahl index. Computed and shown per county, but kept out of the score because it's a quality signal not a volume signal.
- Affordability indices. Affordability matters for buyers; permit volume reflects what's actually being built. We score the latter.
Calibration
Every release of the scoring algorithm is run against an internal baseline our team established by hand-rating FL counties from deep market knowledge. We use that comparison to tune weights and verify the model captures the intuitions we'd apply manually. The calibration data lives in app/calibrate (admin-only).
The score is a starting point — not a recommendation. Every county detail page on PermitFocus shows the per-factor breakdown so you can interrogate which drivers are pulling the score up or down, and decide for yourself whether the factor weights match your business.
Transparency
If you're evaluating PermitFocus and want to dig deeper:
- Every county page lists its raw factor inputs and computed sub-scores
- BPS data is reproducible: census.gov/construction/bps
- BEA population data: bea.gov/data/economic-accounts/regional
- Sources for per-permit ingest are listed in each city's permit-portal documentation (we cite specific ArcGIS / Socrata endpoints internally)