Garage Heater Size Calculator: What Size Heater Do I Need?

Calculate the right garage heater size by entering your garage details below.

What is a Garage Heater?

A garage heater is a heating unit specifically designed to warm garage spaces effectively. Unlike home heating systems, garage heaters are built to handle large, often uninsulated spaces and can provide quick, efficient heating when needed.

Types of Garage Heaters

Type Description Best For
Electric Forced-Air Uses electrical resistance heating with fan distribution Small to medium garages, easy installation
Natural Gas/Propane Burns fuel to generate heat, requires ventilation Large spaces, cost-effective operation
Infrared/Radiant Heats objects directly rather than air Spot heating, workshops, quick warmth
Portable Units Mobile heating solutions Temporary heating needs, flexibility

Benefits of Garage Heating

Workspace Comfort

  • Comfortable working temperature
  • Extended usage of garage space
  • Protection from cold weather
  • Better working conditions

Vehicle Protection

  • Easier vehicle starting in winter
  • Reduced engine wear
  • Protected car batteries
  • Prevents freezing of fluids

Property Protection

  • Prevents frozen pipes
  • Protects stored items
  • Reduces moisture issues
  • Prevents mold growth

Energy Efficiency

  • Zoned heating control
  • Programmable options
  • Targeted heat distribution
  • Reduced energy waste

How to Choose the Right Garage Heater?

Heating Capacity Guidelines

Garage Size Recommended BTU Range Typical Coverage
Single Car (250-350 sq ft) 20,000-30,000 BTU Up to 350 sq ft
Two Car (400-600 sq ft) 35,000-50,000 BTU Up to 600 sq ft
Three Car (650-850 sq ft) 55,000-75,000 BTU Up to 850 sq ft
Large Shop (900+ sq ft) 80,000+ BTU 900+ sq ft

Important Factors in Garage Heater Selection

1. Power Source Considerations

Choose based on availability and cost:

  • Electric:
    • Easy installation
    • No ventilation required
    • Higher operating cost
    • Limited by circuit capacity
  • Gas (Natural/Propane):
    • Lower operating costs
    • Higher heat output
    • Requires proper ventilation
    • Professional installation needed

2. Mounting Options

Consider installation requirements:

  • Ceiling mount
  • Wall mount
  • Floor standing
  • Portable units

3. Safety Features

Essential safety considerations:

  • Overheat protection
  • Tip-over switches
  • Carbon monoxide detectors (for gas units)
  • Cool-touch exteriors

Garage Heater Maintenance

Regular Maintenance Tasks

  • Monthly Checks:
    • Clean or replace filters
    • Check for debris
    • Inspect electrical connections
    • Test safety features
  • Seasonal Maintenance:
    • Professional inspection
    • Vent cleaning
    • Burner adjustment (gas units)
    • Thermostat calibration

Frequently Asked Questions About Garage Heaters

How much does it cost to run a garage heater?

Operating costs depend on:

  • Power source (electric vs gas)
  • Local utility rates
  • Usage patterns
  • Heater efficiency
  • Garage insulation quality

Can I install a garage heater myself?

Installation considerations:

  • Electric units may require new circuit installation
  • Gas units require professional installation
  • Local building codes must be followed
  • Proper ventilation is crucial
  • Safety certifications may be required

How long do garage heaters last?

Expected lifespan varies by type:

  • Electric heaters: 10-15 years
  • Gas heaters: 15-20 years
  • Proper maintenance extends life
  • Usage patterns affect longevity
  • Quality of installation matters

What size circuit do I need for an electric garage heater?

Circuit requirements depend on heater size:

  • Small units (2-3kW): 20-amp circuit
  • Medium units (4-5kW): 30-amp circuit
  • Large units (6-7kW): 40-amp circuit
  • Extra large units: Dedicated 50-amp+ circuit

Are garage heaters safe?

Modern garage heaters include safety features:

  • Automatic shut-off protection
  • Temperature monitoring
  • Sealed combustion chambers (gas units)
  • CSA/UL safety certifications
  • Built-in safety switches

How can I improve garage heater efficiency?

Efficiency improvement tips:

  • Add insulation to walls and ceiling
  • Seal air leaks around doors and windows
  • Install a programmable thermostat
  • Regular maintenance and cleaning
  • Use during optimal temperature conditions

Should I get an electric or gas garage heater?

Consider these factors:

  • Available utility connections
  • Local energy costs
  • Installation requirements
  • Garage size and insulation
  • Desired heating speed and capacity

What's the best temperature for a garage?

Optimal temperature depends on use:

  • Workshop use: 60-65°F
  • Vehicle storage: 45-50°F
  • Living space conversion: 68-72°F
  • Storage only: Above freezing
  • Consider activity level and duration

Do I need a special thermostat for my garage heater?

Thermostat considerations:

  • Must match heater voltage requirements
  • Should handle wide temperature ranges
  • Programmable features recommended
  • Remote control options available
  • Smart thermostats for enhanced control