What size mini split for garage?

What size mini split for garage?


When it comes to heating and cooling a garage, a mini split system can be an excellent choice. Mini splits are versatile, energy-efficient, and offer customizable comfort. However, determining the right size mini split for your garage is crucial to ensure optimal performance and efficiency. In this article, we will delve into the factors to consider when selecting the size of a mini split system for your garage.

Calculating the BTU Requirement

BTU (British Thermal Units) is a unit of measurement used to determine the cooling and heating capacity of HVAC systems. To determine the appropriate size of a mini split for your garage, you need to calculate the BTU requirement. Several factors influence this calculation:

1. Gross Area: Measure the length and width of your garage to determine the square footage. Multiply these dimensions to get the gross area.

2. Insulation: Consider the insulation level of your garage. Well-insulated garages require less cooling or heating capacity compared to poorly insulated ones.

3. Climate: The climate in your region also plays a role in determining the BTU requirement. Hotter climates may require higher cooling capacity, while colder climates may require more heating capacity.

Once you have these factors, you can use an online BTU calculator or consult an HVAC professional to determine the appropriate BTU requirement for your garage.

Choosing the Right BTU Capacity

Based on the calculated BTU requirement, you can select the appropriate BTU capacity for your mini split system. Mini splits typically range from 6,000 BTU to 36,000 BTU capacities. Here are some general guidelines to help you choose:

1. 6,000 – 9,000 BTU: Suitable for small garages or well-insulated spaces up to 300 square feet.

2. 12,000 – 18,000 BTU: Ideal for medium-sized garages or spaces ranging from 300 to 900 square feet.

3. 24,000 – 36,000 BTU: Recommended for larger garages or spaces exceeding 900 square feet.

Keep in mind that these are general guidelines, and it’s essential to consider other factors specific to your garage, such as the number of windows, ceiling height, and the presence of heat-generating equipment or appliances.

Additional Considerations

While BTU capacity is a crucial factor, there are other considerations to ensure optimal performance and efficiency of your mini split system in the garage:

1. Zoning: If your garage has separate areas or rooms, consider a multi-zone mini split system that allows you to control the temperature independently in each zone.

2. Dehumidification: If your garage tends to be humid, consider a mini split system with dehumidification capabilities to maintain a comfortable environment.

3. Energy Efficiency: Look for mini split systems with high energy efficiency ratings (SEER and EER) to reduce energy consumption and operating costs.

4. Installation: Proper installation is crucial for optimal performance. Consult with an HVAC professional to ensure the mini split system is installed correctly and positioned for efficient airflow.


Choosing the right size mini split for your garage is essential for efficient heating and cooling. Calculating the BTU requirement based on factors like square footage, insulation, and climate is the first step. From there, you can select the appropriate BTU capacity and consider additional factors like zoning, dehumidification, energy efficiency, and proper installation. Consulting with an HVAC professional can provide valuable guidance in determining the best mini split system for your garage.


– Energy Star: www.energystar.gov
– HVAC.com: www.hvac.com
– The Spruce: www.thespruce.com