HVAC Load Estimator
Screening-level residential heating and cooling estimate using per-square-foot climate factors. This is not an ACCA Manual J calculation — a Manual J load requires surface-by-surface envelope, orientation, and infiltration inputs. Use this to sanity-check equipment sizing, then have a Manual J run before purchasing.
Total heated and cooled floor area
Your climate region
Building insulation quality
Total windows in conditioned space
Window construction type
Expected number of people
Floor-to-ceiling height
Number of conditioned floors
Results
Cooling Load
39850
BTU/h
Heating Load
60000
BTU/h
Recommended AC Size
3.5
tons
Recommended Furnace Size
60000
BTU/h
Important Note
For accurate sizing, a full Manual J calculation is required per ACCA/IECC standards. This estimator provides general guidance only, and per-square-foot methods tend to run high — treat these as an upper bound and size toward the lower end unless a Manual J says otherwise. Oversized equipment short-cycles, dehumidifies poorly, and costs more.
Typical Equipment Sizes
Code Reference
ACCA Manual J / IECC 2021 – Residential heating and cooling load calculation standards for proper equipment sizing.
Disclaimer: This calculator is for reference only. Always verify with your local building department and a licensed HVAC contractor.