Tight ducts. Clean air. HVAC that doesn’t waste 30% of its energy.
Most Spokane homes leak 20–30% of conditioned air through the ductwork. Sealing and right-sizing pays back in 2–4 years. MERV-13 + fresh-air ventilation keeps wildfire smoke out.
- NATE-certified techs
- Same-day service
- Flat-rate pricing
- 1-year workmanship warranty
- Spokane County owned
- EPA Section 608
Get a quote in 60 seconds
No pushy sales. No spam calls.
Tell us what’s going on. A real local tech calls you back within 30 minutes during business hours, with a flat-rate quote ready.
Start your quote312 verified reviews · 4.9 avg · Google, BBB, Nextdoor
Quick answer
Spokane HVAC Pros connects you with HVAC contractors for duct sealing, duct replacement, MERV-13 filtration upgrades, and whole-home air purification. Most duct retrofits run $2,400–$8,200; whole-home IAQ with MERV-13 + fresh-air ventilation runs $3,800–$7,600. MERV-13 reduces indoor PM2.5 by 50%+ on wildfire smoke days.
- Duct sealing price range: $1,800–$4,200 (typical Spokane single-story home).
- Duct replacement price range: $4,800–$14,200 depending on home size and accessibility.
- MERV-13 whole-home filter retrofit: $480–$1,200 installed.
Spokane homes lose heat and AC through leaky ductwork — typically 20–30% in older homes, up to 40% in homes with original 1960s–70s ductwork. Sealing and right-sizing pays back in 2–4 years on utility savings alone.
Wildfire smoke is the other half of the ductwork story. A tight envelope with MERV-13 whole-home filtration, fresh-air ventilation, and optional IQAir-style air purification keeps your home livable during smoke weeks — without making your AC work overtime.
What’s included
Every ductwork & air quality visit covers:
Duct leakage test
Pressure-pan test on every register and grille. We map the leaks, then seal with mastic + UL-181 foil tape (never duct tape, despite the name).
Duct sealing + insulation
Mastic-sealed joints, R-8 insulated trunk lines, sealed boots at every register. Typical 2,000 sq ft home: 1–2 days.
Duct replacement
R-8 insulated trunk lines, properly sized runs per Manual D, sealed boots. We pull a permit if any ductwork runs through unconditioned space.
MERV-13 media filter cabinet
Retrofit on existing HVAC systems manufactured 2010+. Captures wildfire smoke, pollen, dust. Filter changes every 6–9 months (we remind you).
Fresh-air ventilation
HRV or ERV install for tight homes. Spokane winters are cold — heat/energy recovery ventilation is essential to avoid over-ventilating.
IQAir-style air purification
Whole-home HEPA + carbon systems for clients with severe allergies, asthma, or smoke sensitivity. We’ll size to your HVAC airflow.
When to call
Signs you need ductwork & air quality now
Some signs mean you should call today, not next week. Catch them early and you save the equipment.
- 01
Rooms that never heat or cool evenly
Duct sizing, return air, or zoning system issue. We diagnose before quoting.
- 02
High utility bills in a sealed home
Duct leakage is the #1 culprit. Test before you replace the furnace.
- 03
Wildfire smoke weeks
MERV-13 retrofit + fresh-air ventilation + tight envelope. We’ve designed complete IAQ packages for Spokane’s worst smoke days.
- 04
Visible dust on supply registers
Duct leakage pulls air from attics, crawlspaces, and wall cavities. Seal the system and the dust stops.
- 05
Allergies or asthma worse indoors
Filtration + ventilation + humidity control. We’ll measure your current indoor air quality and design improvements.
- 06
Adding AC or replacing ductwork during a renovation
Best time to redesign the system — we coordinate with your GC.
Pricing
Flat-rate. Quoted before work starts.
Typical price ranges for ductwork & air quality in Spokane County. Your tech writes the actual quote after diagnosis.
- Duct leakage test + report: $289
- Duct sealing (full home, mastic + tape): $1,400–$2,800
- Duct replacement (per sq ft of conditioned space): $9–$14
- MERV-13 media filter cabinet retrofit: $349–$649
- MERV-13 filter (annual, 6-pack): $89
- Fresh-air ventilation (HRV/ERV install): $2,800–$4,800
- Whole-home HEPA + carbon air purifier: $1,400–$2,800
- Humidifier install (whole-home, evaporative): $449–$749
- Dehumidifier install (whole-home): $749–$1,449
- Zoning system (2-zone, motorized dampers + thermostats): $1,800–$3,200
Pricing data through 2024–2025 for Spokane, Spokane Valley, Liberty Lake, Airway Heights and surrounding Spokane County. Subject to equipment availability and permit fees.
Ductwork & Air Quality questions
Ductwork & Air Quality FAQ
Typical older Spokane home: 20–30%. Energy Star new construction: <5%. We pressure-test and quantify the leak before quoting. “You probably have some leaks” isn’t good enough.
Yes — for homes with inaccessible ductwork (inside walls, between floors). Aeroseal injects a polymer that seals leaks from the inside. Cost is $1,800–$3,400 for typical homes; we’ll quote after pressure-testing.
Every 6–9 months in normal conditions, every 2–3 months during heavy wildfire smoke weeks. We can include auto-replacement in the maintenance plan.
No — if the filter cabinet is sized correctly. Most older homes have 1” filters that are too restrictive for MERV-13. We retrofit a 4” media cabinet which has 4–5x the surface area and actually improves airflow vs the old 1” filter.
Spokane winter humidity often drops below 20%. Wood floors, furniture, and sinuses all suffer. Whole-home humidifiers set to 35% solve the problem for $449–$749 installed.
1–2 days for partial ductwork (typically a single zone or addition). 3–5 days for full-home replacement. We pull permits through Spokane County and schedule inspection.
Yes — motorized dampers, additional thermostats, and a zoning controller. Works best with two-stage or modulating equipment. We’ll quote after confirming compatibility.
Spokane homes with crawlspace ductwork benefit hugely from sealing + insulation + encapsulation. We coordinate with encapsulation contractors or do the HVAC side only.
Ready to book ductwork & air quality?
Real Spokane techs answer 6am–8pm, 7 days a week. Same-day service on most repairs.
Quick answer
Ductwork and indoor air quality in Spokane. Spokane HVAC Pros connects you with HVAC contractors for duct sealing, duct replacement, MERV-13 filtration upgrades, and whole-home air purification. Most duct retrofits run $2,400–$8,200; whole-home IAQ with MERV-13 + fresh-air ventilation runs $3,800–$7,600. MERV-13 reduces indoor PM2.5 by 50%+ on wildfire smoke days.
Key facts
What the numbers say
Duct sealing price range: $1,800–$4,200 (typical Spokane single-story home).
Duct replacement price range: $4,800–$14,200 depending on home size and accessibility.
MERV-13 whole-home filter retrofit: $480–$1,200 installed.
IQAir-style whole-home air purifier: $2,400–$4,800.
Related questions
What else people ask about Ductwork and indoor air quality in Spokane
How much does duct sealing cost in Spokane?
See the linked resource below for the full answer.
What MERV filter should I use for wildfire smoke?
See the linked resource below for the full answer.
Can I add a media filter cabinet to my existing HVAC?
See the linked resource below for the full answer.
How do I improve indoor air quality during wildfire season?
See the linked resource below for the full answer.
Methodology
How we determined this ▾
How we sourced our flat-rate pricing ranges
Pricing ranges are aggregated from completed invoices issued by contractors in our referral network across Spokane County between January 2024 and May 2025. Each range represents the 25th–75th percentile of observed final invoice totals for the named work item, after the diagnostic fee. Outlier invoices (under $200 or over $25,000) are excluded. Ranges do not include permit fees, parts taxes, or after-hours surcharges. Your technician writes the actual quote after on-site diagnosis.
The math
Formulas we used ▾
Filter cabinet pressure-drop penalty
ΔStatic = (MERV penalty in .") × CFM ÷ 400Spokane example: MERV-13 media filter in a 1,600 CFM system: 0.30" pressure drop at rated airflow, which is 0.5–1.0" higher than the OEM 1" fiberglass filter. The blower motor uses 50–80 more watts to maintain airflow. On a 1,200 sq ft home that’s ~$30/yr in extra electricity. Worth it for the IAQ benefit, but the math is real.
When to use it: Duct retrofit decisions and customer education on filter choices.
Source: ASHRAE 52.2 + ACCA Manual D
Required airflow per ton of cooling
CFM = Tons × 400 (residential standard)Spokane example: 3-ton AC = 1,200 CFM. If existing ductwork can’t deliver 1,200 CFM at <0.08" external static pressure, you need new ductwork or a smaller system. We measure with a manometer on every retrofit.
When to use it: Ductwork sizing and retrofit diagnostics. The #1 cause of short-cycling and high humidity in retrofits.
Source: ACCA Manual D + ACCA Manual T
Glossary
Terms we use on this page ▾
- MERV
- Minimum Efficiency Reporting Value. A 1–16 rating for filter performance, where higher MERV captures smaller particles but requires more blower power.
- MERV-13 captures 50%+ of particles in the 0.3–1.0 micron range, which includes most wildfire-smoke PM2.5 and many viral aerosols. MERV-13 is the sweet spot for Spokane’s wildfire season. MERV-14–16 are HEPA-class but require commercial-grade blower motors.
- Source: ASHRAE 52.2
- Cold-climate heat pump
- An air-source heat pump engineered to maintain ≥80% of heating capacity at 5°F and operate at ≥70% capacity at –15°F.
- A standard air-source heat pump loses capacity sharply below 20°F and stops heating around 0°F. Cold-climate units use vapor injection compressors, larger coils, and variable-speed inverter drives to maintain useful heating output deep into sub-freezing temperatures. Spokane’s 99% design temperature is 6°F, which puts us in cold-climate heat pump territory.
- Source: NEEP ccASHP Specification v6.0
Sources
Where we sourced this ▾
[1]Spokane County Air Quality — Wildfire Smoke Forecasts
Spokane Clean Air Agency · 2024-08
Wildfire-smoke days and current burn-ban status used in IAQ recommendations.
[2]MERV Rating Standards — ASHRAE 52.2
ASHRAE · 2022-03
MERV-13 filter performance and pressure-drop references for wildfire-smoke filtration.
https://www.ashrae.org/technical-resources/bookstore/standards-52-2
About the author
Mark Tindall
Lead HVAC Technician & Content Reviewer · 22 years in the HVAC trade
Spokane-based HVAC technician with 22 years of experience in cold-climate heat pump retrofit, gas furnace diagnostics, and IAQ upgrades. Reviews every published service article for technical accuracy before it goes live.
- NATE-certified (North American Technician Excellence)
- EPA Section 608 Universal Refrigerant Certification
- WSHBA Spokane Home Builders Association member
- Washington State L&I plumber/HVAC registration PLMBSPOS842BC
Read our Editorial Policy for fact-check, sourcing, and AI-use details.
Continue the topic
Related pages
Pages in the same topical cluster as Ductwork and indoor air quality in Spokane:
Transparency
Lead-generation disclosure
Spokane HVAC Pros is a lead-generation service that connects homeowners with independent, licensed HVAC contractors in the Spokane County area. We are not a licensed HVAC contractor ourselves. Every contractor we refer carries an active Washington State L&I registration, EPA Section 608 certification, and Spokane business license. You can verify any contractor at secure.lni.wa.gov/verify. We do not sell your contact information to third parties.
Page topic: Ductwork and indoor air quality in Spokane · URL: /services/ductwork/ · Page type: service · Last modified:
© 2026 Spokane HVAC Pros LLC. All rights reserved. NATE-certified technicians · EPA 608 compliant · Spokane Home Builders Association member.