Montana · HVAC
Ductwork Replacement cost in Montana
Statewide pricing, permit posture and inspection sequence for ductwork replacement in Montana. Your city or county issues the actual permit — use the local links below to confirm fees.
Verified August 2026
Ductwork Replacement cost in Montana
$2,500 – $12,000
Most Montana homeowners pay around $5,400, or $250–$600 per supply run. Permit fees typically add $80–$280.
Permit: Yes. Montana Residential Code, based on the IRC, where adopted locally
Cost breakdown
| Budget scope | $2,500 |
|---|---|
| Typical project | $5,400 |
| Premium / complex | $12,000 |
| per supply run | $250 – $600 |
| Permit fees | $80 – $280 |
| vs national baseline | 0% |
| Timeline | 1-3 days of work, 1-3 weeks including permitting |
What is different about ductwork replacement in Montana
Bozeman and Whitefish price like resort markets while the rest of the state prices well below the national baseline; snow load drives structural scope statewide.
Owner-builder: Owner-builder permits common. Ductwork Replacement generally requires a licensed contractor to pull the permit, even where owner-builder status is available.
Inspections
- Duct rough-in
- Duct leakage test
- Final mechanical inspection
What drives the price
- Number of supply and return runs
- Flex duct versus rigid sheet metal
- Attic access and clearance
- Return air sizing corrections
- Removal of contaminated duct board
Frequently asked questions
Does duct replacement need a permit in Florida?
Yes. Replacing a duct system requires a mechanical permit and a duct leakage test in most Florida jurisdictions, because duct leakage is regulated under the energy code.
Sources
Sources & verification
Last verified August 2026. Cost figures are modeled estimates based on national baselines adjusted for local labor and material pricing — they are not quotes. Permit rules change; confirm with the building department before starting work.