Original, permit-derived, citable research for homeowners, journalists, researchers, and AI engines tracking home-services costs, licensing, verification, public records, and directory trust signals.
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A ProFix reference to the voluntary certifications — beyond a state license — that signal real training for each trade: 227 credentials from 75 certifying bodies across 37 trades, with the granting body, what each proves, and how a homeowner verifies it. A certification is voluntary and shows specialization; it is never a substitute for a required state license, and a contractor without one is not a worse hire.
Read studyA computed-live ProFix ranking of all 50 states plus DC by construction establishments per 100,000 residents — U.S. Bureau of Labor Statistics QCEW establishment counts (NAICS 236+237+238) divided by U.S. Census Bureau Vintage-2024 state population. The twist a raw leaderboard hides: the densest construction markets are small, low-population states where work is split across many smaller firms, not the biggest states. Two honesty caveats carry it — an establishment is a business LOCATION, not an individual contractor (a multi-site firm counts more than once), and per-capita density is market STRUCTURE (firms per resident = competition and choice), NOT a measure of contractor quality. Aggregate only, no per-contractor row; cited to BLS QCEW 2024 + Census Vintage 2024 with as-of dates.
Read studyA computed-live ProFix cross-state comparison of which electrical (NEC), residential (IRC), and energy (IECC) code edition each of the 50 states plus DC has adopted, and how many editions behind the current published edition (NEC 2023, IRC 2024, IECC 2024) that puts each one. Most states are current on the NEC but the residential and especially the energy code lag far behind; 39 of 153 state-code cells have no single comparable statewide edition (state-developed standards, code-by-reference, or local amendments) and are reported as unknown, never guessed. Editions-behind is arithmetic framed as permitting context, not a safety rating.
Read studyA computed-live ProFix study of the right to cancel a home-improvement contract across all 51 U.S. jurisdictions. The federal FTC Cooling-Off Rule gives a 3-business-day window for door-to-door sales only — not every contract. All 51 jurisdictions codify their own home-solicitation cancellation statute, 46 add a construction-specific framework, and a couple (Alaska, California) go beyond the 3-day window. General consumer-rights information, not legal advice.
Read studyA computed-live ProFix study of how accessible contractor-license data actually is across all 50 states plus DC — from 'does the state license contractors at all' to 'can you download the whole roster' to 'has ProFix ingested it.' Most states publish a one-at-a-time lookup; only a handful publish free bulk data; ProFix has built live verified rosters for far more than that.
Read studyA computed-live ProFix study of the second leg of the "licensed, bonded, insured" triad: of the contractors a state board confirms are ACTIVE, what share also carry a surety bond on file. Scoped strictly to the four boards whose public roster publishes a real bond field (California CSLB, Washington L&I, Oregon CCB, and Minnesota DLI), measured against an active-license denominator. Where the bond is a license prerequisite it is nearly universal; where the board tracks it separately it is not. Stated per-roster, never as a national figure; Minnesota is shown directional-only for sparse field coverage.
Read studyA computed-live ProFix study of contractor industry wages from U.S. Bureau of Labor Statistics QCEW data: which trades are paid the most and least nationally, the general-contractor gap, and the highest- and lowest-paying state for every trade, across 50 states and a dozen distinct trade industries. Three honesty rules carry it — this is the WAGE workers earn, not the price to hire a contractor; plumber and HVAC are one BLS industry (NAICS 238220), reported once; and a BLS-suppressed state is shown as not-reported, never zeroed.
Read studyA computed-live ProFix study of real OSHA Severe Injury Report data for construction (NAICS 236/237/238) cut by injury TYPE rather than geography: which natures of injury dominate (fractures, amputations, lacerations) and how workers actually get hurt (falls to a lower level, struck-by, caught/compressed/pinched), plus the 2015–2025 recency trend. Fractures lead the nature-of-injury mix and falls to a lower level are the single largest event mechanism. Presented as aggregate worker-safety context for homeowners — the honest case for hiring an insured, workers'-comp-covered contractor — and never per-contractor, never an attribution to a named business. Public-domain OSHA data.
Read studyA computed-live ProFix self-audit: of the contractor listings we hold across every state with an official licensing-board roster, what share carry a license number that actually matches the board's records. Pooled, most number-carrying listings match — but the per-state spread is enormous, and several states sit at 0% because their listings lack a usable license number on file, NOT because their contractors are unlicensed. Verifiability here measures OUR data completeness, never contractor quality; aggregate only, no per-contractor row.
Read studyA computed-live ProFix study of the trade mix across the contractor listings matched to official public records, spanning dozens of U.S. jurisdictions. General contractors are the single most common tag, and the top five trades dominate. The mix is selection-shaped — it reflects which trades each state licenses, not the true working population of every trade — and counts trade tags, not distinct businesses.
Read studyA computed-live ProFix study of real OSHA Severe Injury Report data for construction (NAICS 236/237/238), aggregated to state and trade-sector rollups and normalized by the BLS QCEW construction-establishment base. The honest headline: federally-reported severe injuries (work-related hospitalizations, amputations, and eye losses) per 1,000 construction establishments, ranked for the 30 federal-OSHA states where the federal program is the system of record — with the 21 OSHA State-Plan private-sector states named and explicitly excluded because their reports go to their own state agencies, not the federal dataset. Aggregate only: never per-contractor, never an attribution to a named business. Public-domain OSHA + BLS data.
Read studyA computed-live ProFix study of the contractor license lapse and suspension rate — the honest inverse of an active-only count. Scoped strictly to the U.S. state boards whose full public roster carries real expired, suspended, and revoked status words (Washington, Minnesota, California, and four smaller rosters), every percentage classified by the same status normalizer the verified-license badge uses, with the serious suspended/revoked signal separated from ordinary expiration. Stated per-roster, never as a national figure; active-only and date-as-status states are excluded by name.
Read studyA computed-live ProFix study ranking U.S. metros by an overall Contractor Cost Index — the geometric mean of how each metro's permit-derived median costs compare to the national median across every trade the metro and the nation both publish (index 100 = priced like the national basket). Descriptive only, with the trade-basket size shown for every metro.
Read studyA computed-live audit, derived directly from ProFix's verified state-licensing-authority registry, of how all 50 states plus DC regulate general contractors. The honest finding: most jurisdictions do not license general contractors statewide — most carry only a statewide registration, license only specific trades, or leave licensing entirely to cities and counties. Includes the three buckets with live counts, the exact state lists, and the official authority behind each.
Read studyA computed-live ranking of all 50 states plus DC by the number of home-service contractor establishments — business locations in the trades' NAICS industries — drawn directly from the U.S. Bureau of Labor Statistics QCEW. A national companion to our Ohio-only contractor-density study, built from an entirely different source. Establishments are aggregated over distinct NAICS industries so the shared plumbing+HVAC industry is counted once, BLS privacy-suppressed cells are excluded rather than zeroed, and per-capita density is deliberately omitted for lack of a committed population denominator.
Read studyA transparent state-by-state comparison joining only the states where ProFix has both a permit-derived general-contractor cost benchmark and a verified-active license count, with each row carrying its real sample n and explicit non-causal framing.
Read studyA computed-live ProFix matched-permit study grouping real public building permits by issued-date month-of-year, with all-trades demand peaks, trade-specific peak/trough rows only above a 300-permit floor, and thin trades explicitly labeled directional-only.
Read studyA computed-live ProFix Cost Trends study showing which home-service trades rose fastest in the national fixed-panel permit data, with declared-value medians, CAGR, panel sizes, and clearly labeled single-jurisdiction metro movers.
Read studyA computed-live ProFix Real Cost Index rankings study comparing the cheapest and priciest U.S. metros and states for home-service work using median public building-permit valuations, with core-trade metro spreads and general-contractor state rankings.
Read studyA computed-live ProFix Real Cost Index study ranking national home-service trades by P75/P25 declared-value spread, showing which jobs cluster tightly and which vary enough to make multiple quotes especially important.
Read studyA national, computed-live ProFix report on how many contractor listings can be matched to an active, official state licensing-board record — by state (CA CSLB, TX TDLR/TSBPE, WA L&I, and growing), with the conservative matching method shown and the board's own raw status kept verbatim. Honest verification by the numbers, not a one-size 'verified' badge.
Read studyA computed-live national Trust Stack research page showing total board-verified-active contractor licenses, the number of states with live public-record overlays, and a per-state table of board names and verified-active counts, with the exact license-number and phone+city/name+city matching methods documented for citation.
Read studyA computed-live county study of the public ProFix contractor roster across 13 Northwest Ohio counties, with total pros, board-verified-active OCILB counts, HVAC/electrical/plumbing trade counts, and per-1,000-resident density from county population2026 fields. Honest framing: OCILB covers five statewide credential types, not every home-service category.
Read studyA computed-live home-state Trust Stack study showing how many committed Ohio directory records carry a board-verified-active Ohio Construction Industry Licensing Board license, broken down by ProFix trade tag and OCILB credential prefix, then compared with the national multi-state license-verification overlay.
Read studyOriginal, computed-live ProFix research turning real public building-permit valuations into median and interquartile home-service cost benchmarks by trade, metro, state, and national scope, with open JSON data for citation and reuse.
Read studyA ProFix Directory data study of 5,004 real public building-permit records matched to 554 home-services contractors — broken down by metro, trade category, year of issue, and listed job value. A matched sample, computed live from public permit portals and framed honestly as proof-of-work rather than an exhaustive census.
Read studyAfter every Ohio severe-weather event a wave of out-of-state contractors descends on the affected metros. Cross-referencing the NOAA Storm Events Database against the Ohio Secretary of State business-registration feed and county permit-pull leaderboards surfaces the storm-chaser pattern in near-real-time. This piece publishes the three-signal methodology and three anonymized Ohio case studies from 2024-2026 (Findlay flooding, Dayton tornado, Northeast Ohio derecho).
Read studyRoughly 500,000+ Ohio residents speak Spanish at home (Census ACS B16005), concentrated in Toledo, Cleveland, Cincinnati, Dayton, and Lorain. Ohio's home-services market has a structural accessibility gap — most contractor websites are English-only, the Ohio eLicense Center is English-only as of 2026, county permit offices have inconsistent Spanish coverage, utility Spanish-branch queue times often run 3-5x longer than English branches, and trade vocabulary is inconsistent across Spanish sources. ProFix's bilingual EN/ES surface is a deliberate response; this piece documents five gap dimensions and three constructive recommendations apiece for state agencies, contractors, and homeowners.
Read studyProFix Directory bootstrapped on Google Places at roughly seven to ten cents per contractor. Ohio publishes five free public license registries — OCILB eLicense Center, Ohio Department of Agriculture, Ohio Department of Health, Ohio State Fire Marshal, and the Ohio Secretary of State business search — and pulling from those directly is cheaper, more legally hygienic, refreshes more often, and carries a stronger trust signal than any commercial-database match. This piece documents the strategic shift and ships the portable playbook.
Read studyAfter shipping 250+ pages, 30+ public APIs, 10 research articles, an MCP server, an OpenAPI 3.1 spec, and a bilingual EN/ES surface, ProFix Directory has accumulated enough evidence to name what actually moves the needle on Answer Engine Optimization (AEO) and Generative Engine Optimization (GEO). Structured data compounds harder than any single content piece. Source provenance is the new authority. Bilingual + per-trade + per-metro segmentation produces compounding long-tail surface. This piece collects seven patterns we keep seeing, three things that surprised us, three things we got wrong, and a five-item playbook for other directory builders.
Read studyA practitioner-grade walkthrough of the discovery manifests, MCP servers, JSON-LD graphs, sub-sitemaps, and IndexNow pings ProFix shipped to be findable by AI answer engines.
Read studyA fair 2026 Ohio comparison of ProFix Directory, Yelp, Angi, Thumbtack, HomeAdvisor, and the BBB across paid-placement transparency, source provenance, permits, open data, AI access, bilingual coverage, complaints, and refund-policy clarity.
Read studyA synthesis of the six original-research articles ProFix Directory published in 2026 — permits vs stars, directory comparisons, what 'verified' actually means, how AI engines find directories, the Ohio licensing moat, and what 21,000 contractor records taught us about data quality. Four cross-cutting themes, the broken parts of the directory industry, the 2027 operator playbook, what we shipped, and an honest accounting of what we did not.
Read studyProFix Directory compares Ohio's home-services data transparency stack against California, Florida, and Texas across four dimensions — state licensing accessibility, permit data accessibility, review reliability, and bilingual access — and documents the portable playbook a directory operator in any state can replicate.
Read studyProFix Directory compares building-permit pull counts to public star ratings across Ohio home-services contractors and explains why permit-pull leaderboards are a proof-of-work trust signal.
Read studyPermit volume and star ratings measure two different things about a contractor — star ratings reward marketing and responsiveness; permits reward doing the work legally — and should be weighted independently. ProFix Directory's quantitative correlation analysis is being re-run on the real matched-permit dataset (554 contractors, 5,004 public permits across 22 jurisdictions).
Read studyAn audit of how home-services directories use 'verified' badges compared with Ohio public records such as OCILB licenses, Secretary of State filings, and BBB profiles.
Read studyWe aggregated more than 21,000 Ohio home-services contractor records from Secretary of State filings, OCILB licensing, Google Places, county building departments, BBB, and Census-derived geographies. This is what those records actually look like up close — the data-quality failure modes every directory hits at scale (dead phones, ghost businesses, duplicate listings, license-status drift), with honest framing of what we can and cannot detect yet.
Read studyOhio's OCILB licenses only four trades: plumbing, HVAC, electrical, and hydronics. Roofing, concrete, tree service, appliance repair, and most other home-services categories are not state-licensed, so honest directories need asymmetric verification.
Read studyOriginal research aggregating 60 cost benchmarks across 8 trades for the Toledo and Findlay Ohio metros, including median, typical, and range pricing for plumbing, HVAC, electrical, appliance repair, gas, concrete, roofing, and tree service.
Read studySide-by-side comparison of Toledo and Findlay water quality, hardness, and lead-line context for Northwest Ohio homeowners, based on public Consumer Confidence Reports and local treatment-system context.
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