ProjectCostPro Construction estimating tools
Home › Data updates

Data updates & changelog

Cost data goes stale — wage rates move, materials swing, sources restructure. This page logs every recalibration, source re-verification, and methodology change, with dates, so you can see exactly when and why a number changed.

By Martin Lashgari, Ph.D., P.E., PMP · Last reviewed July 2026

Why this page exists

Most cost sites quietly overwrite their numbers and never say so. We treat the data like an engineering document under revision control: when a rate, a formula, or a source changes, it's logged here. Every calculator's footer also carries a per-page “Updated” date driven from the same history. See the methodology and sources for how the numbers are built in the first place.

July 2026

  • 33 rate citations reclassified after Homewyse withdrew the pages they pointed to. Homewyse removed a large number of its per-service cost pages. Where we had cited one, the rate itself is unchanged — it was calibrated while the page was live — but the citation no longer resolves, so those rows are now labelled internal assumption rather than pointing at a dead link. Affected: asphalt driveway, carpet, concrete driveway, countertops, crawl space, electrical panel, solar, sump pump, and water heater. A further set of Homewyse citations is under review; we only change a citation once the page has actually been checked, because a blocked request and a deleted page look identical to an automated checker.
  • Calculator data now loads independently per file. Previously, if any one of a calculator's four data files failed to load, the page discarded all of them and fell back to its built-in defaults — which can differ from the published figures by more than 5%. Each file is now applied on its own, so one failed request no longer changes the other three.
  • HVAC ductless mini-split recalibrated. The whole-home HVAC calculator was pricing each mini-split zone as a full single-condenser system, so a 3-zone job ran high (about $18,400–$32,100). It now shares one condenser across zones and prices per indoor head, landing near $11,000–$17,800 — in line with the dedicated mini-split calculator. The whole-home “large” scenario is now a high-efficiency heat pump.
  • Source links re-audited in a real browser; 189 dead HomeGuide references repaired. HomeGuide restructured its cost URLs, retiring 64 pages our calculators cited. An earlier automated status-check had missed this: HomeGuide's CDN returns a blanket 403 to datacenter clients, so genuine 404s looked like ordinary bot-blocking. We re-verified every HomeGuide link from a real browser and repointed all 189 affected references to live equivalents — a specific live page where one still exists, otherwise HomeGuide's live cost index.
  • Per-metro cost tables added to every calculator. Each page now shows the same estimate run at eight major metros' real labor and material multipliers, so you can see regional spread before entering your ZIP.
  • “What moves this price” sensitivity analysis added to every calculator. A tornado view, computed by running each calculator's own engine across every input, ranking which choices move the estimate most.
  • Markup classification made explicit across all 1,127 rate rows. Each rate now states its markup basis directly rather than inferring it from wording, so a copy edit can never silently change pricing. Verified zero change to any published band.
  • Project Simulator rebuilt. Configured project instances, shareable plans that reproduce on any browser, and a professional plan report with PDF and CSV export.
  • Bid-check gained per-line scope. Tick exactly which line items a contractor's quote covers and the comparison band rebuilds from just those items.
  • Performance & polish. All hero images re-optimized (site image weight cut from 21.9 MB to 6.1 MB), a self-hosted typeface, branded share cards, and range bars on the cost table.

June 2026

  • Siding installed bands recalibrated after a review found the high end running hot; the typical re-side band was widened and re-anchored to per-square-foot installed rates.
  • Five comparison guides and the 2026 national cost table published — every figure reconciled to the matching calculator's engine output.
  • Monte Carlo cost simulation added to every calculator — 10,000 trials returning an optimistic / most-likely / safer-budget spread instead of a flat low-to-high band. See the methodology.
  • 109 BLS wage references migrated to the current Bureau of Labor Statistics deep-link format after the old occupational-wage pages were retired.
  • Federal tax-credit copy corrected to past tense. Sections 25C and 25D lapsed December 31, 2025; Section 30C lapsed June 30, 2026. No calculator subtracts an expired credit.

May 2026 — launch

  • Launched with 52 line-item cost calculators spanning outdoor, exterior, interior, mechanical, kitchen & bath, remodel, and structural work.
  • ZIP-zone regional pricing, a materials/labor/equipment/permit/markup breakdown on every result, and a bid-check tool to sanity-check contractor quotes.
  • Rate ranges independently derived from BLS wage data, manufacturer pricing, public cost guides, and trade-association data — every row carrying a source and a date.

How to follow changes

Each calculator's footer shows when that page was last materially updated — whether the change was copy, layout, schema, or the underlying rates — and individual rate rows carry their own source and review dates. For the full picture, this page is updated whenever a material change ships. Spotted a number that looks off? The contact page is the fastest way to flag it — corrections are logged here.

Estimates are planning ranges, not contractor quotes. We don't replace your contractor, permit, or inspector.