ACCA Manual J · Residential HVAC Load Calculations

Manual J Load Calculation Service

Permit-ready ACCA Manual J load calculations for residential construction — room by room, from your actual plans, using WrightSoft. Nationwide, since 1995.

What Manual J tells you Manual J is the ACCA standard method for calculating the peak heating and cooling load of a home. It gives you the number every equipment and duct decision should be built from — not a square-footage estimate, not a rule of thumb.

What a Manual J load calculation covers

A full Manual J load calculation accounts for every factor that drives the heating and cooling load of a home:

Room-by-room sensible and latent cooling loads
Room-by-room heating loads
Window orientation, SHGC, and solar gain by exposure
Actual wall, ceiling, and floor assemblies — not code minimums
Infiltration and controlled ventilation
Internal gains from people, lighting, and equipment
Local design conditions for your specific climate zone

What comes after Manual J

Manual J gives you the load. Manual S uses that load to select equipment matched to your actual design conditions — not nameplate tonnage. Manual D sizes the duct system to deliver conditioned air to every room at the right flow rate.

All three are available as a package or individually. Most permit submittal packages require at minimum a Manual J. Many jurisdictions also require Manual S and Manual D. See our pricing page for current rates and turnaround times.

Who we work with

We work with HVAC contractors, builders, architects, and homeowners across all 50 states. Residential is our primary work — we also take on select light commercial. Reports are delivered in 24–48 hours, permit-ready. See our areas served for climate-specific pages.

Permit-ready Manual J, Manual S, and Manual D — delivered in 24–48 hours from your plans. See current pricing and get started.

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