🌡️HVAC

HVAC Load Calculator

Calculate heating and cooling load requirements based on square footage, insulation, climate zone, and windows.

Calculate HVAC Load

Home Square Footage

Climate Zone

Insulation Quality

Ceiling Height (ft)

Window Exposure

Number of Occupants

Understanding HVAC Load Calculations

A proper load calculation (based on ACCA Manual J) ensures your HVAC system is correctly sized. An oversized system short-cycles, wastes energy, and fails to dehumidify. An undersized system runs constantly and cannot maintain comfort.

Key Factors

Climate Zone: Determines base heating and cooling requirements per square foot.
Insulation: Poorly insulated homes can need 30-40% more capacity.
Windows: Large or west-facing windows add significant solar heat gain.
Occupants: Each person adds approximately 400 BTU of heat to the space.

When to Use This Calculator

This calculator provides a quick estimate for residential HVAC sizing. For commercial buildings, new construction, or complex layouts, a full Manual J calculation by a licensed HVAC contractor is recommended.