1. What is Garage Unit Heater Sizing?

Definition: This calculator determines the appropriate size (in BTU/h) for a garage unit heater based on garage area, heat loss per square foot, and garage-specific factors.

Purpose: It helps homeowners and contractors select properly sized heating equipment for garages to ensure efficient operation and comfort.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Required heater size (BTU/h)
• \( A \) — Garage floor area (square feet)
• \( \text{BTU/ft}^2 \) — Heat loss per square foot (typically 30 BTU/h·ft²)
• \( F_g \) — Garage factor (accounts for insulation, ceiling height, etc.)

Explanation: The base heat requirement is calculated from area and BTU/ft², then adjusted by the garage factor for specific conditions.

3. Importance of Proper Heater Sizing

Details: Correct sizing ensures efficient operation, prevents short-cycling, maintains comfortable temperatures, and extends equipment life.

4. Using the Calculator

Tips: Enter the garage area in square feet, heat loss per square foot (default 30 BTU/h·ft²), and garage factor (default 1.0). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical BTU/ft² value for garages?
A: Most garages use 30 BTU/h per square foot, but this can range from 20-50 depending on insulation and climate.

Q2: How do I determine the garage factor?
A: Use 1.0 for standard garages, 0.8 for well-insulated, or 1.2-1.5 for poorly insulated or high-ceiling garages.

Q3: What if my garage has high ceilings?
A: Increase the garage factor by 0.1 for each foot over 8 feet, or calculate based on cubic feet instead of square feet.

Q4: Should I round up the heater size?
A: Yes, select the next available size if your calculation falls between standard unit sizes.

Q5: Does this account for extreme climates?
A: No, for very cold climates (below 0°F regularly), consider increasing the BTU/ft² value by 10-20%.