HVAC
How to Size and Estimate Mini-Split Installation
Preliminary method for sizing a mini-split by area and estimating installation by zones.
Mini-split sizing starts with the area to condition, and the cost follows the number of indoor zones. This is a preliminary estimate, not a definitive HVAC design.
THE SHORT ANSWER
How do you size and estimate a mini-split?
Use the area for an indicative capacity, then multiply zones by unit and install cost. A 1,200 sq ft space suggests about 30,000 BTU, and 2 zones at $900 + $600 plus a $300 line set totals $3,300.
Estimate the capacity
A rough rule is about 25 BTU per sq ft. For 1,200 sq ft that is around 30,000 BTU, but a real load calculation is needed for a final size.
- Area to condition
- Indicative capacity
- Zones
- Line set
Count the zones
Each indoor unit is a zone. Multi-zone systems cost more in units and install labor but condition separate rooms.
Add install and line set
Install labor is per zone and the line set covers refrigerant lines, wiring and insulation.
This is preliminary
Use the Mini-Split Sizing and Installation Cost Calculator to plan, but a final size and quote need a professional load calculation, inspection and permitting. These figures are not a definitive HVAC design.