Changelog
We ship improvements regularly to make your Manual J calculations faster and more accurate. Here's what's changed.
March 10
Your reports now include full ACCA Manual S compliant equipment sizing with three tiers (Budget, Recommended, Premium). Equipment capacities are derated to your actual design conditions — not just nameplate ratings — so you see exactly how the system performs on the hottest and coldest days of the year.
Heat pump reports now show the thermal balance point temperature, supplemental strip heat requirements (exact kW and recommended standard size), and what percentage of heating hours the heat pump covers on its own.
Equipment recommendations now display SEER2, EER2, HSPF2, AFUE, and COP at design conditions — giving contractors every rating they need for permit applications and customer proposals.
Every report now shows whether the recommended equipment meets ACCA Manual S 3rd Edition sizing rules, with clear Compliant or Review Needed indicators.
Gas furnace reports now show input and output BTU/hr at your elevation, with automatic altitude derating per ACCA guidelines for homes above 1,000 ft.
March 9
Upgraded our blueprint reading AI to a next-generation vision model for more accurate extraction of window schedules, wall sections, insulation specs, and architectural details from your plans.
Load calculations now automatically adjust for your building's elevation using ACCA Manual J altitude correction factors. Homes at higher elevations get more accurate infiltration and ventilation estimates.
Redesigned our proprietary HVAC IQ Score™ with a three-tier reliability model: Calculation Foundation (ACCA methodology compliance and physics validation), Building Specificity (how tailored the calculation is to your building), and Pipeline Verification (cross-checks against climate-zone expectations). Every report now reflects a more accurate picture of calculation confidence.
When you enter R-values, U-factors, SHGC, or ACH50 during upload, those exact values are now guaranteed to appear in your Building Envelope Specs section — no overrides from extraction.
March 5
Fixed an issue where referral codes were not being applied during account creation. Referral links now work correctly across all signup paths.
You can now override foundation wall and floor R-values directly from the envelope inputs form, giving you full control over insulation assumptions.
Your report now displays the foundation R-value used in calculations for full transparency.
Fixed an issue where room-by-room load totals could differ slightly from building-level totals. They now match exactly.
Refined foundation heat loss modeling for crawlspace constructions, resulting in more accurate heating and cooling load estimates.
Homes with daylight and walkout basements now receive more precise infiltration estimates that account for the additional exposed surface area.
March 4
Room-by-room breakdowns now display the actual room labels extracted from your blueprints (e.g., "Primary Bedroom", "Kitchen") instead of generic names.
March 3
You can now download a PDF copy of your report directly from the Share Report modal. Shared report links no longer require an account to view.
February 27
Completely reworked humidity-driven cooling calculations using wet-bulb temperature data for your climate zone. Reports now reflect real-world moisture loads more accurately.
Reports now factor in site wind exposure (shielded, normal, or exposed) when calculating infiltration loads, giving more accurate results for lakefront and hilltop homes.
February 26
If your blueprints specify an energy recovery ventilator, the report now applies the appropriate ventilation load reduction.
Improved reading of window schedules and manufacturer specifications directly from architectural drawings for more precise window area calculations.
February 24
Above-grade basement walls are now modeled with the correct R-values based on your climate zone per IECC 2024 requirements.
February 23
The sample report page now shows a real, interactive report preview so you can see exactly what you get before uploading your blueprints.
February 19
Room-by-room tables now include heating and cooling CFM columns, making it easier to size ductwork for each room.
Room-by-room breakdown now features grouped column headers and a dedicated sensible cooling column for clearer equipment selection.
February 18
Fixed an issue where solar heat gains through windows could be under-reported on some multi-story homes.
February 15
Improved how we calculate building perimeter for foundation heat loss, resulting in better alignment with field measurements.
Added a "New Project" card to the dashboard grid and fixed the New Analysis button for paid subscribers.
February 12
Reports now account for cathedral and vaulted ceilings, including the increased roof surface area and different insulation values compared to flat attic ceilings.
Solar heat gain factors have been recalibrated to match ACCA Manual J Table 3A values for more accurate cooling load estimates by orientation.
You can now manually specify wall R-value, ceiling R-value, window U-factor, SHGC, and ACH50 to override blueprint-extracted values.
February 11
Reports now include a detailed room-by-room breakdown showing heating and cooling loads for every room in your home.
February 10
Major accuracy pass across all load calculation components. Results are now consistently within 10% of manual engineering calculations.
January 19
Fixed an issue where solar gains were not correctly using window data extracted from blueprints.
January 15
Fixed an edge case where using Stripe Link with a different email could cause checkout issues.
January 14
Updated platform dependencies to the latest security patches.
January 13
You can now purchase a single report for $27 without a subscription — perfect for one-off projects.
Added support for 7,600+ additional ZIP codes, bringing total coverage to over 34,000 locations across the US.
Resolved a billing issue where some customers could be charged twice during checkout.
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