Quick answer
For most Puget Sound homes, an HRV is the right call: it recovers heat from outgoing stale air without transferring moisture, which suits our damp-outside winters. An ERV earns its premium in very tight new construction where winter indoor air gets uncomfortably dry, since it returns some moisture along with the heat. Either satisfies Washington's energy-code push toward mechanical ventilation in tight homes — the ducting plan matters more than the box.
- Both systems bring in fresh outdoor air and exhaust stale indoor air through a core that recovers most of the heat you'd otherwise throw away.
- The difference is moisture: an HRV moves heat only, while an ERV moves heat plus a portion of humidity between the airstreams.
- In our marine climate — damp outside most of the winter — the HRV's moisture rejection is usually the feature, not the flaw.
- Installed pricing runs $3,500–$8,000 for either type; how much new ducting the layout needs drives where you land in that range.
- New tight townhomes and deep-energy remodels are exactly where Washington's energy code expects heat-recovery ventilation.
What does each option cost installed in the Seattle area?
The equipment itself is a fraction of the invoice — dedicated ventilation ducting is what separates a $3,500 job from an $8,000 one. A new tight townhome in Ballard with an accessible mechanical closet sits at the low end; retrofitting fresh-air ducting through a finished 1980s two-story is the high end.
| Option | Typical installed range | What that covers |
|---|---|---|
| HRV system, installed | $3,500–$7,000 | Heat-only recovery core; the standard recommendation for Puget Sound's cool, humid-outside winters. |
| ERV system, installed | $4,000–$8,000 | Heat-plus-moisture recovery; the pick for very tight homes fighting dry winter indoor air. |
What changes the price
- Ducting scope — a dedicated fresh-air duct run through finished walls and floors is the single biggest line item.
- Whether the unit can tie into existing HVAC ducting or needs its own fully independent distribution.
- House tightness and size, which set the required airflow rating and unit class.
- Access: crawlspace, attic, or mechanical-room placement changes labor hours substantially.
- No rebate offsets — Washington and PSE don't currently fund ventilation equipment, so plan on full installed cost.
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 an HRV works
Two fans run continuously: one exhausts stale indoor air, one pulls in fresh outdoor air, and both streams pass through a heat-exchange core without mixing. In January, the outgoing 68°F indoor air pre-warms the incoming 40°F outdoor air, so you get fresh air without paying full price to reheat it. Moisture stays in whichever airstream it arrived in — outbound humidity leaves the house.
How an ERV works
Same two-fan, two-airstream layout, but the core is moisture-permeable. Along with heat, a portion of water vapor migrates between the streams — in winter, some of the humidity in your outgoing air transfers back into the dry incoming air instead of being exhausted. That's a genuine benefit in a super-tight home whose winter indoor air drops uncomfortably dry, and irrelevant in a home that already runs damp.
Pros and cons, honestly
HRV
Pros
- Actively exhausts indoor moisture — a match for the PNW's condensation-prone winters
- The default recommendation for our marine climate, so sizing and support are well-trodden
- Slightly simpler core, generally the lower-cost option of the two
- Continuous fresh air without the heat penalty of cracking windows in January
Cons
- Can over-dry a very tight home in a cold snap — the one scenario where the ERV wins
- Needs dedicated ducting in most retrofits, which drives cost
- Filters and core need cleaning on a schedule most homeowners forget
ERV
Pros
- Returns some winter moisture to the incoming air — relief for dry-air complaints in tight construction
- Tempers humid outdoor air in warm spells before it enters the house
- Same continuous fresh-air and heat-recovery benefits as an HRV
- Increasingly the spec in high-performance builds where indoor dryness is a known issue
Cons
- Costs more for a benefit many Puget Sound homes never notice
- Retains moisture — the wrong direction for a house already fighting dampness
- Moisture-permeable cores are more sensitive to neglect than HRV cores
Which one should you choose?
Choose an HRV when
Your home shows any sign of winter dampness — fogged windows, a humid basement, or musty closets on exterior walls — or it's simply a typical Puget Sound house of average tightness. Heat-only recovery plus active moisture exhaust is exactly what this climate calls for, and it's the configuration local energy-code guidance leans toward. If you're unsure, the HRV is the safe default here; the ERV is the special case.
Choose an ERV when
You have a very tight envelope — a new townhome, a Passive-House-adjacent build, or a remodel with serious air sealing — and the household complains about dry winter air, static, or cracking trim. In that scenario the ERV's moisture return solves a real comfort problem the HRV would make slightly worse. It's also worth a look if summer humidity intrusion bothers you during our increasingly warm Augusts.
Also consider: fixing spot ventilation first
If bath fans are weak, unvented, or dumping into the attic, upgrading them costs far less than a recovery ventilator and removes a large share of household moisture at the source. We check spot ventilation before recommending either box.
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: Indoor air quality services →
- Book: Humidity control →
- Book: Financing options →
- Compare: Humidifier or Dehumidifier: Which Does Your PNW Home Actually Need? →
- Compare: Whole-Home vs Portable Air Purifier: Which Handles Smoke Season Better? →
- Compare: Ductless Mini-Split vs Central HVAC: The Whole-Home Decision →
- Indoor air quality basics for Puget Sound homes →
- How ductwork moves air through your home →
- All heating & air comparisons →
Common questions
Does Washington's energy code require an HRV or ERV?
The code requires mechanical ventilation in new and substantially remodeled homes, and it increasingly favors heat-recovery ventilation in tight construction because exhaust-only fans waste heated air. Which recovery type you pick is your choice — the code cares that fresh air arrives continuously and efficiently.
My new Ballard townhome feels stuffy — is this why?
Very likely. Tight new construction traps cooking odors, CO2, and moisture that older, leakier houses exhaled through their walls. That stuffiness is the classic symptom that mechanical ventilation is undersized or switched off — check that the existing system is actually running before assuming you need new equipment.
Will an HRV help with window condensation in winter?
Yes — persistent condensation means indoor moisture has nowhere to go, and an HRV exhausts it around the clock while recovering the heat. It's one of the most effective fixes for winter window sweat in tight Puget Sound homes, though single-pane glass will still fog before double-pane does.
Do HRVs and ERVs run all the time, and what does that cost?
They're designed for continuous low-speed operation, and the fans are small — think tens of watts, a few dollars a month at PSE's roughly $0.12/kWh. The heat the core recovers typically outweighs the fan energy many times over in winter.
Last updated: 2026-07-05