Ductless mini-splits: room-by-room comfort without ducts

A ductless mini-split pairs an outside compressor with one or more wall, floor or ceiling heads inside — no ducts, refrigerant lines only. In homes without ductwork (hydronic heat, old housing stock, additions, garages), it is usually the only serious option, and its inverter compressors put it among the most efficient cooling equipment sold in the US, with top models above 25 SEER2.

The trade the industry under-explains: single-zone systems are more efficient and cheaper per zone than multi-zone. A branch box feeding four heads forces one compressor to serve unequal loads, and oversized multi-zone condensers cycle inefficiently at low demand. Where budget allows, two single-zone systems often beat one dual-zone. And resist head-per-room maximalism — a well-placed head cools adjacent open space, and doors-open layouts share air better than the brochure admits.

Frequently asked questions

What does a mini-split cost per zone?

Indicative 2026 ranges: $3,000–$5,500 installed for a quality single-zone system, $8,000–$15,000 for 3–4 zone multi-head configurations. DIY-oriented pre-charged kits run cheaper but sacrifice warranty and commissioning quality. Market reference ranges, not quotes.

Mini-split or window units?

Window ACs win on first cost ($150–$800 vs thousands) and renter compatibility. Mini-splits win on everything else: 2–3× the efficiency, 20+ dB quieter, no stolen window, real heating capability, and a 15-year service life. The crossover point: if you will stay 5+ years and cool most of the summer, ductless usually pays.

By state and by size

State rules and climates: all 50 states. Sizing: BTU by square footage. Brands: Carrier, Trane, Lennox, Goodman, Midea.

Other equipment types: Central AC · Heat pump · Window AC · Portable AC.