The Garage Apartment or Bonus Room That Never Stays Cool
Updated September 2026
That extra room over the garage or the odd-shaped addition was supposed to be a guest suite, home office, or gym. Instead, it’s a sweatbox by June and a fridge by December. Central AC can’t reach it, and window units turn the space into a noisy, dripping mess.
Old West Minisplits posts the price up front. One zone for that bonus room is $2,000 flat. No in-home quote, no standoff over the final bill. Just a ductless mini split that cools through 100-degree summers and handles mild winters without a furnace.
Why Central AC Fails in Bonus Rooms
Most bonus rooms sit on top of garages or jut out from the main footprint. Ducts have to stretch too far, and the extra length bleeds cold air before it arrives. The thermostat in the living room never knows the room is still 85 degrees.
Even if the ducts reach, the insulation in those spaces is often thin or missing. The roof bakes in the Texas sun, turning the room into a radiator. A window unit can’t keep up, and portable ACs just shuffle hot air around.
What’s Included in the Flat Price
The $2,000 flat price covers the mini split unit, labor, line set up to 25 feet, standard electrical tie-in, refrigerant, testing, and cleanup. If the wall needs a patch of paint, we’ll grab a Home Depot match. No trip fees, no hidden charges.
These are new installs only. If the existing mini split needs repair, that’s a separate service call. Exceptions are rare but up front: a very long line set, a panel upgrade the house already needed, or unusually difficult mounting.
How It Works in a Bonus Room
A single-zone mini split mounts on the wall or ceiling, blowing cold air directly into the space. The outdoor unit sits on a pad or bracket, connected by a small line set through the wall. No ductwork means no lost efficiency.
Because it’s a heat pump, it reverses in winter to pull warmth from outside. Central Texas winters don’t drop below freezing often, so the mini split handles the cold without a backup furnace. The room stays comfortable year-round.
How we compare
| Factor | Old West Minisplits | The Usual Contractor |
|---|---|---|
| Upfront Cost | $2,000 flat for 1 zone (bonus room). | Typically $3,000-$6,000 per zone after an in-home visit. |
| Install Time | One day, no return trips. | Multiple visits for quote, install, and punch list. |
| Noise Level | Indoor unit runs at 25-30 decibels (quieter than a whisper). | Window units roar at 50+ decibels, portable ACs rattle. |
| Winter Heating | Heat pump handles mild winters without a furnace. | Window units don’t heat; portable heaters are inefficient. |
Straight answers
Is the $2,000 price for a new install or a repair?
The flat price is for new installs only. Repairs and service calls are quoted separately.
What if my bonus room is far from the outdoor unit?
The $2,000 price includes a line set up to 25 feet. Longer runs may require an extra charge, but we’ll tell you before starting.
Do I need a separate electrical panel for the mini split?
Most bonus rooms can tie into existing circuits. If the house needs a panel upgrade, that’s a separate job for a licensed electrician.
Can the mini split handle Texas summers?
Yes. These units are rated for 115-degree outdoor temperatures. They’ll keep the room cool even when the rest of the house is struggling.
Related guides
Get the number today
No walkthrough, no sales pitch. Tell us the rooms and we'll tell you the price.
Get My Flat Price