Version History

Per-calculator version notes for I Love MEP tools.

Last updated: September 19, 2026

Site Release v1.3.51

  • v1.3.51: Fixed the Reference Library CSS. Blog and reference pages (/blog/*) were loading with unstyled markup on some deployments because the CSS was linked via a relative path (../assets/css/style.css) that broke when the URL was served with or without a trailing slash. All /blog/ pages now use absolute paths (/assets/css/style.css).
  • v1.3.51: Same absolute-path fix applied to JS, favicon, breadcrumb, footer, and inline navigation on all 9 reference pages.
  • v1.3.51: No other content, schema, or calculator behaviour changed.

Site Release v1.3.50

  • v1.3.50: Save inputs — every calculator now remembers the last values you entered. Open the same tool tomorrow and your inputs are back exactly where you left them (per browser, via localStorage).
  • v1.3.50: Shareable links — every calculator page gets a "🔗 Share link" button. Click it to copy a URL that opens the calculator with your inputs pre-filled. Perfect for sending a completed sizing to a colleague or client.
  • v1.3.50: Copy result — a "📋 Copy result" button in the actions row copies the calculation output plus a share-back link to the clipboard for pasting into email, WhatsApp, or a report.
  • v1.3.50: When inputs are restored on page load, an inline notice explains it and offers a "Start blank" reset.
  • v1.3.50: The "Clear" button now also wipes the saved state for that tool.
  • v1.3.50: All new features are additive — no changes to any calculator's formulas or output layout.

Site Release v1.3.49

  • v1.3.49: Rebranded the /blog/ section as the "Reference Library" — same URLs, evergreen framing, dates removed from the UI to remove any "when is the next post" expectation.
  • v1.3.49: Added a client-side site search (press "/" or click Search in the header) covering all 47 calculators, 47 guides, 8 references, and 11 static pages. Zero maintenance — the index is generated from the site data.
  • v1.3.49: Added a "Save" star on every calculator, guide, and reference page — users bookmark tools they use often via localStorage.
  • v1.3.49: Added a "Recently viewed" + "Your saved tools" strip that appears on the home page automatically as soon as the user has activity in either list.
  • v1.3.49: Removed the year "2026" from the cost-benchmarks reference title so it does not date itself.
  • v1.3.49: Injected a single site-utility.js across all 154 pages for the above features.

Site Release v1.3.48

  • v1.3.48: Published 8 long-form reference articles at /blog/ covering tender review, standards comparisons, cost benchmarks, chiller specification, voltage drop, MEP due diligence, chilled water vs VRF, and sprinkler hazard classification.
  • v1.3.48: Added BlogPosting, FAQPage, and BreadcrumbList JSON-LD to every article.
  • v1.3.48: Added a "Blog" entry to the primary navigation across every page.
  • v1.3.48: Added preconnect and dns-prefetch link tags for pagead2.googlesyndication.com and googletagmanager.com to reduce LCP.
  • v1.3.48: Registered 9 new URLs (index + 8 articles) in sitemap.xml.

Site Release v1.3.47

  • v1.3.47: Published 47 new per-calculator engineer guides at /guides/<slug>.html, each with the formula the tool uses, variable definitions, a worked numerical example, standards references, common-mistakes list, and FAQ.
  • v1.3.47: Added Article, HowTo, FAQPage, and BreadcrumbList JSON-LD schema to every new guide.
  • v1.3.47: Added a "Read the full guide" banner to every calculator page linking to its matching guide.
  • v1.3.47: Added a "Per-calculator engineer guides" section to resources.html grouped by discipline.
  • v1.3.47: Registered 47 new guide URLs in sitemap.xml.
  • v1.3.47: Bumped static asset query strings for cache invalidation.

Site Release v1.3.46

  • v1.3.46: Expanded the four Resources comparison guides (cable sizing vs voltage drop, CFM vs TR, fire alarm battery, sprinkler vs fire water tank) from short overviews into full long-form engineering articles with formulas, worked examples, common mistakes, and FAQ sections.
  • v1.3.46: Added FAQPage JSON-LD to the four comparison guides for improved rich-result eligibility.
  • v1.3.46: Added byline attribution, published date, and updated date to each guide.
  • v1.3.46: Enhanced the About page with editorial standards, review process, expanded author bio, and advertising disclosure to strengthen E-E-A-T signals.

Site Release v1.3.45

  • v1.3.45: Restored active stylesheet loading on every page after the performance package left style.css as preload only.
  • v1.3.45: Bumped static asset query strings so browsers fetch the corrected CSS/JS references.

Site Release v1.3.43

  • v1.3.43: Removed the founder credentials placeholder comment from about.html.
  • v1.3.43: Added VideoObject JSON-LD to embedded YouTube tutorial pages.
  • v1.3.43: Added HowTo JSON-LD to the 47 public calculator pages for clearer workflow markup.

Cooling Load Estimator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Duct Sizing & Velocity Checker

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Airflow & CFM Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Chilled Water Pipe Sizing Tool

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Exhaust Fan Sizing Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Sprinkler Density & Coverage Planner

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Fire Pump Sizing Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Fire Hose Reel / Hydrant Demand Tool

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Fire Water Tank Capacity Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

FM200 / Clean Agent Quantity Estimator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Cable Sizing & Voltage Drop Planner

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Electrical Load Schedule Builder

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Transformer Sizing & Spare Capacity Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Generator Sizing & Starting Load Planner

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Power Factor Correction & Payback Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Fire Alarm Battery Backup Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Fire Alarm Loop Load Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Fire Alarm DIP Switch Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

CCTV Storage Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Data Rack Power & UPS Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Access Control Door Hardware Planner

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Water Demand Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Pump Head Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Drainage Pipe Sizing Assistant

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Water Tank Capacity Planner

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Hot Water Demand Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Conduit Fill Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Short Circuit Current Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Lighting Lux Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Water Pipe Pressure Drop Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Breaker Size Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

kVA to Amps Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Ampacity Derating Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Drainage Slope Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.

Pump Horsepower Calculator

  • v1.3.6-prelaunch: Added methodology, standard profile support, version notes, and direct PDF report download.
  • v1.3.5: Calculator page added with sample data, warnings, and print-ready report layout.