Room by Room HVAC Calculator
Calculate heating and cooling loads for individual rooms. Perfect for mini-split sizing, ductwork design, and zone-by-zone HVAC planning for bedrooms, living rooms, kitchens, and offices.
Room Information
Walls exposed to outside conditions
Room Floor Area
144 sq ft
Volume: 1296 cubic feet
Windows, Doors & Insulation
Total window area in this room
Exterior doors only (standard door = 20 sq ft)
Design Temperatures
Peak outdoor temperature for cooling design
Minimum outdoor temperature for heating design
Room Load Calculation
Calculate precise heating and cooling loads for individual rooms to properly size mini-splits, design ductwork, and plan zoned HVAC systems.
- Room-specific load calculations
- Window and door heat transfer
- Exposed wall considerations
- Mini-split sizing recommendations
- Airflow requirements (CFM)
Perfect for: Mini-split sizing, ductwork design, zoned systems, and room-by-room comfort optimization.
Room-by-Room Calculator Usage Guide
Calculate precise heating and cooling loads for individual rooms. Perfect for mini-split sizing, zoned systems, and ductwork design. Follow these guidelines for accurate room-specific results.
Room Information Input
Room Basics
- Room Type: Select bedroom, living room, kitchen, bathroom, or office
- Dimensions: Measure length, width, and ceiling height accurately
- Orientation: Direction room faces (affects solar gain)
- Exposed Walls: Count walls touching outdoors
Windows & Doors
- Window Area: Total square feet of all windows
- Door Area: Exterior doors only (standard door = 20 sq ft)
- Insulation Level: Poor, average, good, or excellent
- Design Temps: Local heating/cooling design conditions
Room Type Guidelines
Bedrooms
Typically have 1-2 exterior walls, moderate window area, minimal equipment loads. Focus on nighttime comfort.
Living Rooms
Often have large windows, multiple occupants, entertainment equipment. May have high solar gains.
Kitchens
High internal heat from appliances, cooking. Often require extra cooling capacity and ventilation.
Bathrooms
Small spaces with moisture concerns. Often have exterior walls and require ventilation.
Measurement Tips
- Room dimensions: Measure inside wall to inside wall
- Window area: Measure glass area, include all windows and skylights
- Exposed walls: Count walls that touch outdoor air or unconditioned spaces
- Orientation: Use compass app or note which direction windows face
- Door area: Only count doors to outside (not interior doors)
Applications for Results
Mini-Split Sizing
Use room load to select proper capacity mini-split unit. Match BTU/hr output to calculated load for optimal performance.
Ductwork Design
Room CFM requirements determine duct sizes and register selection for proper airflow distribution.
Zoned Systems
Group similar-load rooms into zones or create dedicated zones for high-load spaces.
Understanding Results
Results show heating and cooling loads for the specific room, plus required airflow (CFM) and equipment recommendations. Use these values for mini-split selection, duct sizing, or zone design. The calculator accounts for room orientation, envelope characteristics, and typical usage patterns.
Next Steps
- • Calculate loads for all rooms in your home
- • Use whole-house calculator for total loads
- • Consider equipment sizing for central systems
- • Consult HVAC professional for installation
Additional Resources
Professional Installation
Room load calculations provide essential data for system design. Professional installation ensures proper equipment selection, ductwork design, and system commissioning for optimal comfort and efficiency in every room.