Quick answer
For a Puget Sound home with sound existing ductwork, central ducted HVAC is usually the cleaner whole-home answer. For homes with no ducts at all — 1920s Craftsmans, baseboard-heated houses, ADUs — ductless wins decisively, because retrofitting ductwork can cost more than the equipment itself. Between two and four zones, ductless stays competitive; beyond that, per-head economics stack up and a ducted system often pencils better.
- This is a whole-home heating AND cooling decision — if you're only weighing cooling options, our ductless vs central AC guide is the better read.
- The existing-duct question decides most cases: reuse good ducts and central wins on cost; retrofit ducts into a finished house and ductless wins by default.
- Ductless zoning is real: each head has its own thermostat, so the Tacoma bungalow's bedroom can sit at 64°F while the living room holds 70°F.
- Head-count economics matter — a single zone runs roughly $5,000–$8,000, but multi-zone systems climb to $8,000–$18,000 as heads are added.
- PSE's ductless rebate (up to about $1,500) is aimed squarely at homes replacing electric baseboard or wall heat.
What does each option cost installed in the Seattle area?
Whole-home ductless pricing is driven almost entirely by zone count, so treat the multi-zone range as a spectrum, not a quote. Central pricing assumes your ducts are usable; if a duct retrofit enters the picture, that line item alone can swing the entire comparison.
| Option | Typical installed range | What that covers |
|---|---|---|
| Single-zone ductless | $5,000–$8,000 | One outdoor unit, one indoor head — the ADU, the converted garage, or the one impossible room. Not whole-home coverage on its own. |
| Multi-zone ductless (whole home) | $8,000–$18,000 | One or two outdoor units feeding three to five indoor heads, sized per room. Cost scales with zone count and line-set runs. |
| Central ducted heat pump system | $12,000–$20,000 | Outdoor unit plus air handler on existing ductwork, conditioning every room from one thermostat. Assumes ducts are present and serviceable. |
What changes the price
- Ductwork reality: sound existing ducts favor central heavily; no ducts (or crushed crawlspace runs) favor ductless just as heavily.
- Zone count: every added ductless head adds equipment, refrigerant piping, and labor — past four zones, the totals converge with ducted.
- Rebates: WA HEAR (up to $8,000, income-eligible) covers qualifying heat pumps in either format; PSE's ductless rebate up to ~$1,500 targets electric-baseboard conversions specifically.
- Aesthetics and placement: wall-mounted heads are visible in every zoned room; ducted delivery hides in ceilings and floors.
- Permits and code: both need mechanical and electrical permits, and Washington energy code credits either format when it's a qualifying heat pump.
Ranges are representative Seattle / Puget Sound installed prices, not a quote — your home's specifics set the real number. Eco gives you an upfront price before any work begins.
How do they work differently?
How a ductless mini-split works
One outdoor heat pump connects by slim refrigerant lines to individual indoor heads mounted in each zone. Every head is its own delivery point with its own temperature sensor — heat or cool arrives directly in the room, with no ducts in between to leak or lose energy. The tradeoff is visibility: conditioning happens where you can see the equipment.
How central ducted HVAC works
A single indoor unit — air handler or furnace — conditions air in one place and a blower distributes it through supply ducts to every room, with return ducts carrying air back. Delivery is invisible and whole-home by nature, but ducts in unconditioned crawlspaces and attics leak and lose heat along the way, which is why duct condition matters as much as equipment choice.
Pros and cons, honestly
Ductless mini-split system
Pros
- No ductwork required — the only practical retrofit for many older Seattle homes and ADUs
- True room-by-room zoning with independent temperature control
- Zero duct losses; every watt of conditioning lands in the room it's meant for
- Quiet indoor heads and inverter-driven outdoor units
- PSE rebate support up to ~$1,500 when replacing electric baseboard heat
Cons
- Wall-mounted heads are visible in every conditioned room
- Per-zone costs stack quickly in larger homes
- Each head has a filter to clean — maintenance points multiply with zones
- Bedrooms without their own head can lag behind the rest of the house
Central (ducted) HVAC
Pros
- Conditions every room, including hallways and baths, from one system
- Invisible delivery — no equipment on walls, just registers
- Single filter location makes maintenance and high-MERV filtration simple
- Usually cheaper than ductless when good ducts already exist
- One thermostat and simple controls the whole household understands
Cons
- Needs ductwork — retrofitting ducts into a finished home is invasive and expensive
- Duct leakage in crawlspaces and attics silently wastes conditioned air
- One thermostat means one temperature; zoning requires added dampers and cost
Which one should you choose?
Choose ductless when
Your home has no ducts and never did — a Wallingford Craftsman on radiators, a Tacoma bungalow with wall heaters, a split-level running baseboards in every room. It's also the answer for additions, converted garages, and backyard ADUs where extending ductwork is impractical. If different family members genuinely want different temperatures, ductless delivers that without any add-on zoning hardware. And if you're leaving electric baseboard behind, PSE's ductless rebate sweetens the deal.
Choose central HVAC when
Your home already has serviceable ductwork — most gas-furnace houses do — and you want every room conditioned without equipment on the walls. Central also wins in larger homes where whole-home ductless would need five or more heads, and in households that prefer one thermostat over a fleet of remotes. Have the ducts inspected and sealed as part of the project; a tight duct system erases most of ductless's efficiency argument.
Also consider: the hybrid layout
Plenty of Puget Sound projects land on both: a ducted heat pump serving the main floors through existing ducts, plus one ductless head for the addition, bonus room, or ADU the ducts never reached. It's often cheaper than forcing either format to cover the whole footprint.
Ready to compare for your home?
Get honest numbers for both options side by side — an upfront range, the considerations, and the rebates you qualify for, before any work begins.
Continue exploring
- Book: Ductless installation & replacement →
- Book: Heat pump installation & replacement →
- Book: Duct cleaning →
- Compare: Variable-Speed vs Single-Stage HVAC: What the Premium Buys →
- Compare: Heat Pump vs Air Conditioner: Which Should Seattle Homes Add? →
- Compare: Heat Pump vs Electric Furnace: The All-Electric Showdown →
- Ducted heat pump vs ductless mini-split →
- Ductless vs central AC (cooling-focused guide) →
- All heating & air comparisons →
Common questions
Is ductless enough to heat a whole house through a Washington winter?
Yes, when zoned properly — cold-climate ductless systems carry homes through Puget Sound winters routinely, and our mid-20s°F design temperatures are comfortably within their range. The design question isn't capability, it's coverage: every space needs a head or a clear path to conditioned air.
How many ductless zones does a typical home need?
A common pattern is three to five: living area, primary bedroom, and one or two more for remaining bedrooms or a lower level. Open floor plans need fewer; chopped-up layouts need more. This is exactly what a Manual J room-by-room load calculation answers — insist on one before comparing bids.
Do wall heads hurt resale value?
We haven't seen evidence they do in this market — buyers here increasingly recognize ductless as premium equipment, especially in homes that never had cooling. That said, taste varies, and recessed ceiling-cassette heads exist for owners who want a lower profile.
Which format is cheaper to run?
Head-to-head with identical usage, ductless usually edges out ducted because nothing is lost in duct runs — leaky crawlspace ducts can waste a meaningful share of what the system produces. But a well-sealed duct system narrows the gap to almost nothing, so the honest answer depends on your ducts, not the brochure.
Last updated: 2026-07-05