Whole-Home Ductless (Mini-Splits in Every Room) vs Central Ducted: Real Cost Comparison

The Whole-Home Decision

When a heat pump needs to handle every room of your house — not just supplement an existing furnace — the choice between ductless mini-splits and a central ducted system becomes the single biggest decision in your project. Both technologies use the same refrigeration cycle. Both deliver heating and cooling. But they distribute conditioned air in fundamentally different ways, and that difference affects cost, efficiency, comfort, aesthetics, and maintenance for the next 15-20 years.

This guide covers whole-home systems only. If you're adding a heat pump to one or two rooms while keeping an existing furnace, see our ductless mini-split for one room guide. For dual-fuel setups where the heat pump shares duty with a furnace, see our dual-fuel setup guide.

Whole-Home Ductless: How It Works

A whole-home ductless system uses one or two outdoor compressor units connected via refrigerant lines to individual indoor heads in each room or zone. Each indoor unit has its own thermostat, fan speed, and temperature setting. Refrigerant travels directly from the outdoor unit to each head — no ductwork, no air handler, no blower losses.

For a typical 2,000-2,500 sq ft New England home, a whole-home ductless system requires 3-6 indoor heads depending on room count and layout. Most systems use a multi-port outdoor unit (one outdoor unit connected to 3-5 heads) rather than individual 1-to-1 pairs, which reduces outdoor equipment and simplifies installation.

Central Ducted: How It Works

A central ducted heat pump uses a single outdoor compressor unit connected to an indoor air handler. The air handler contains a blower fan, evaporator coil, and filter. It pushes conditioned air through a duct system — the same type of ductwork used by a traditional furnace or central air conditioner — with supply registers in each room and return air grilles pulling air back to the handler.

The appeal of ducted systems is simplicity: one outdoor unit, one indoor unit, one thermostat, and invisible operation. The air handler lives in a utility closet, basement, or attic. Only the supply and return vents are visible in living spaces. For homeowners who dislike the look of wall-mounted mini-split heads, ducted systems solve the aesthetics problem entirely.

Modern ducted heat pumps from Bosch, Carrier, Daikin, and Mitsubishi offer variable-speed compressors and inverter-driven blowers that rival ductless efficiency — if the ductwork is properly sealed and insulated. The critical qualifier is duct condition. Even the best ducted heat pump can't overcome leaky, uninsulated ducts running through unconditioned spaces.

Head-to-Head Comparison

Here's the definitive breakdown across every factor that matters. Each category has a clear winner — but the overall winner depends on which factors matter most for your specific home:

The Hidden Factor: Duct Losses

This is the single most underrated factor in the ducted vs. ductless decision. Even a "good" duct system loses 10-15% of energy through leaks, conduction through duct walls, and temperature gain/loss in unconditioned spaces. Older duct systems in uninsulated attics or crawl spaces can lose 25-40% of the energy the heat pump produces.

Ductless systems have zero duct losses because refrigerant — not air — travels between the outdoor and indoor units. Refrigerant lines are insulated and lose less than 1% of energy in transit. This is why a ductless system rated at 22 SEER2 often outperforms a ducted system rated at 22 SEER2 in real-world conditions.

The takeaway: if your ducts are in poor condition — running through an unconditioned attic, crawl space, or have visible disconnections — ductless eliminates the problem entirely. If your ducts are well-sealed and run through conditioned space (like a finished basement), the efficiency gap shrinks to 5-10%.

Real-World Scenarios: Which System Wins?

Theory is helpful, but real homes have specific constraints that tip the decision one way or the other. Here are four common New England scenarios we encounter regularly:

Total Cost of Ownership: 15-Year Comparison

Upfront cost is only part of the picture. Energy efficiency, maintenance, and equipment lifespan determine which system is actually cheaper over its lifetime. Here's the full 15-year cost of ownership for a 2,200 sq ft New England home, comparing a 4-zone ductless system to a ducted air handler with existing ductwork:

The 15-year total cost is remarkably similar — within $600 of each other. Ductless costs more upfront but saves on energy. Ducted costs less upfront but higher ongoing energy expense erases the savings over time. The tie-breaker isn't cost — it's comfort, zone control, and whether you have usable ductwork.

Making Your Decision: A Framework

After analyzing hundreds of whole-home heat pump installations across New England, here's our decision framework. Answer these four questions and your path becomes clear:

New England Rebates Apply to Both Systems

Both ductless and ducted whole-home heat pump systems qualify for the same state rebate programs. Your rebate amount depends on system capacity and your income level, not the distribution method. Current programs:

• Massachusetts (Mass Save): Up to $10,000 per home. Income-eligible households may qualify for no-cost installations.
• Connecticut (Energize CT): Up to $2,250 per system for qualifying cold-climate heat pumps.
• Rhode Island (Clean Heat RI): Up to $11,500 for income-eligible households; standard rebates for all income levels.
• New Hampshire (NHSaves): $250/ton standard rebate for oil/gas/propane switch (up to $1,250). Enhanced rebate of $1,250/ton for electric resistance replacement (up to $6,250). R-32/R-454B refrigerant required.
• Vermont (Efficiency Vermont): Up to $5,000 for cold-climate heat pumps with ENERGY STAR certification.
• Maine (Efficiency Maine): Up to $8,000 for income-eligible households; standard rebates of $2,000-$4,000 for all homeowners.

Federal HEAR rebates (up to $8,000 for income-qualified households) also apply to both system types and stack with state programs. These are direct rebates — not tax credits — and remain funded through 2031 or until funds are exhausted.