How Much to Cool a Casita or ADU in Central Texas.

A casita or accessory dwelling unit in Central Texas needs reliable cooling without the cost of extending ductwork. Mini splits offer a compact, efficient solution, but pricing varies based on zones, line set length, and electrical requirements.

Flat pricing, same everywhere we work

Every install is wired to code by our TDLR-licensed contractor. Long line-set runs, panel upgrades or unusual mounting can add cost, and we tell you up front, before any work starts. For market context, see our Austin mini split cost guide: typical Central Texas quotes run $3,000 to $5,000 for a single zone.

General sizing guide

General sizing guidance. Actual BTU needs vary with insulation, ceiling height, sun exposure and windows, which is why we confirm sizing against your specific space before quoting.

Why Mini Splits Fit Small Spaces Like Casitas

Casitas and ADUs typically range from 300 to 800 square feet, making a single-zone mini split the most common choice. A 12,000 to 18,000 BTU unit handles the load for most detached studios or guest houses. The compact design avoids bulky ductwork, preserving ceiling and wall space. Since these structures often lack existing HVAC, a ductless system eliminates the need for retrofitting or adding vents.

The flat pricing model simplifies budgeting. A single-zone install costs $1,500, covering the indoor and outdoor units, line set, electrical hookup, and labor. For larger casitas or multi-room ADUs, two or three zones run $2,500 and $3,500 respectively. These prices assume standard conditions, such as accessible exterior walls and no need for panel upgrades. Honest exceptions, like long line sets or difficult mounting, are disclosed upfront.

What Drives Cost Up or Down for ADU Installs

Line set length is the most frequent variable. Standard installs include up to 25 feet of line set, but casitas farther from the main house may require longer runs, adding cost. Electrical requirements also matter. Most ADUs connect to the existing panel, but older or undersized panels may need upgrades, which fall outside the flat-rate pricing. Exterior mounting difficulty, such as stucco or brick walls, can extend labor time but won’t change the flat rate unless the job exceeds standard conditions.

TDLR-licensed contractors perform the work, ensuring compliance with Texas regulations. Most single-zone installs finish in one day, with testing completed before the crew leaves. The flat-rate pricing covers all materials and labor, including a Home Depot run for touch-up paint if needed. Since mini splits are heat pumps, they provide both cooling and heating, eliminating the need for a separate furnace. This dual functionality is particularly useful for Central Texas, where winters are mild but occasional cold snaps require reliable heat.

Questions

Can I add a mini split to a detached casita without a dedicated circuit?

Most casitas require a dedicated 240-volt circuit for the outdoor unit. If the existing panel lacks capacity, a panel upgrade may be necessary, which is not included in the flat-rate pricing. Discuss electrical needs during the initial assessment to avoid surprises.

How many zones do I need for a 600-square-foot ADU with a bedroom and living area?

A single 18,000 BTU unit often suffices for open layouts, but separate zones may improve comfort if the bedroom and living area have different temperature needs. Two zones cost $2,500, while a single zone is $1,500. Consider airflow and room usage when deciding.

Does the flat rate include removing an old window unit or wall AC?

No. The flat-rate pricing covers new mini split installations only. Removing existing units or patching walls after removal is additional work. If you need this service, discuss it upfront to arrange separate pricing.

We install across Central Texas. See the Austin mini split cost guide, full Central Texas service area or Austin mini split installation.