DIY Mini Split for Garage
A DIY mini split is the best way to heat and cool a garage, and you can install one yourself in an afternoon with no HVAC technician and no ductwork. For most garages, a 12,000 BTU unit that plugs into a standard 115V outlet is the right starting point. Use the table below to match your garage to the correct unit, then click through to buy it.
What size mini split do I need for a garage?
Garages run hotter and colder than living spaces because they are often uninsulated and have large doors, so size up compared with a normal room. Plan on roughly 25 to 30 BTU per square foot for an uninsulated garage, and match your garage to a unit below.
| Your garage | Approx. floor area | Recommended Z1 Air unit |
|---|---|---|
| 1-car or small workshop | Up to 300 sq ft | 9,000 BTU 115V or 12,000 BTU 115V, from $1,899.99 |
| 2-car garage, most common | 300 to 550 sq ft | 12,000 BTU 115V if insulated, 18,000 BTU 230V if not, from $1,999.99 |
| 3-car or detached garage | 550 to 900 sq ft | 18,000 BTU 230V, $2,599.99 |
| Oversized or multi-bay shop | 900 to 1,500 sq ft | Dual zone 24,000 to 30,000 BTU, from $3,999.99 |
115V or 230V for your garage?
The biggest decision for a garage is electrical. The 9,000 and 12,000 BTU Z1 Air units run on a standard 115V outlet, the same kind you already have in the garage, so most one and two-car garages need no electrical work at all. Step up to a 230V circuit only for the 18,000 BTU unit or a dual-zone system, which you would choose for a large, detached, or multi-bay garage. If your garage already has a 115V outlet and holds two cars or fewer, the plug-in route is the simplest path to a comfortable space.
Why a DIY mini split is ideal for a garage
Garages rarely have ductwork, which rules out central air and makes a ductless mini split the natural fit. A Z1 Air system ships with a pre-charged R-454B line set, so you connect the fittings by hand without a vacuum pump, gauges, or refrigerant handling, and no EPA Section 608 certification is required for the quick-connect models. Because every unit is a heat pump, the same system that cools your garage gym in July keeps your workshop warm in January. A 9,000 BTU unit delivers 9,400 BTU of heating, and the 18,000 BTU unit delivers a full 18,000 BTU, enough for most climates.
Our top pick for most garages
For a typical one or two-car garage, the Z1 Air DIY 12,000 BTU 115V mini split is the unit to buy. It plugs into a standard outlet, reaches 23 SEER2 efficiency, cools and heats up to about 450 sq ft of uninsulated garage, and arrives with everything you need to install it yourself.
Buy the 12,000 BTU 115V Mini Split, $1,999.99
Frequently asked questions
What size mini split do I need for a 2-car garage?
A typical 2-car garage of 400 to 600 sq ft needs about 12,000 to 18,000 BTU. Because garages are usually uninsulated and have large doors, size up: a 12,000 BTU unit suits an insulated 2-car garage, while an 18,000 BTU unit is the safer choice for an uninsulated garage or a hot climate.
Can I install a mini split in my garage myself?
Yes. Z1 Air DIY systems ship with a pre-charged R-454B line set, so you connect the fittings by hand without a vacuum pump, gauges, or refrigerant. No HVAC technician and no EPA Section 608 certification are required for the quick-connect models, and most garage installs take an afternoon.
Do I need a 230V outlet for a garage mini split?
Not always. The 9,000 and 12,000 BTU Z1 Air units run on a standard 115V outlet, so most one and two-car garages need no electrical upgrade. Larger 18,000 BTU and dual-zone systems use a 230V circuit.
Will a mini split heat my garage in winter?
Yes. Every Z1 Air mini split is a heat pump that both cools and heats. The 9,000 BTU model delivers 9,400 BTU of heating and the 18,000 BTU model delivers 18,000 BTU, enough to keep a garage gym or workshop comfortable through winter in most climates.
Does a garage need to be insulated for a mini split to work?
A mini split works in an uninsulated garage, but insulation lets a smaller unit do the job and cuts running costs. If your garage is uninsulated, size up one step and seal the large gaps around the door for the best results.