Cooling a Garage, Shop, or Outbuilding in Louisiana: What Works

A garage workshop, a detached shop, or a converted outbuilding is some of the most valuable space on your property — until Louisiana summer makes it unusable. Cooling these spaces is a different problem from cooling a house, and the usual shortcuts disappoint.

Why the shortcuts fall short

• Window units struggle with the heat load of an uninsulated garage, run constantly, and still lose the humidity battle.
• Portable ACs are the least efficient option made — much of their cooling goes out the exhaust hose.
• Extending the house ductwork steals capacity from the rooms your system was sized for, and garages shouldn't share return air with the home in the first place.

What actually works: a dedicated mini-split

A ductless mini-split gives the space its own properly sized capacity, real humidity removal, heat for the winter months, and its own thermostat — so you condition the shop only when you're using it. No ductwork required, and no impact on the house system.

Two things that make or break it

Insulation first. An uninsulated metal building fights the equipment all day. Even modest wall/ceiling insulation and sealing the big air leaks dramatically shrinks the equipment you need — and the power bill. Size it honestly. Garages and shops have high, spiky loads (a metal roof, an opening bay door). Sizing from real conditions — not a square-footage chart — is the difference between a shop that holds 75° and one that never gets there; the same discipline covered in our sizing guide.

Thinking about reclaiming your shop or garage? Tell us about the space — we'll give you the straight answer on what it needs and whether it's worth it.