Ductwork Replacement Cost in Tempe & the East Valley (2026) — Replace, Repair, or Seal
Phoenix attic ducts sit in 150° air for months. What full replacement, partial runs, and sealing cost, how to tell which you need, and why a new AC on bad ducts is money lost.
In most Valley homes the ductwork runs through the attic, where summer temperatures pass 140°. Flex duct sags, seams pull apart, and insulation breaks down. A duct system leaking 20 to 30% of its air into the attic is common in older homes, and it means you're paying to cool your attic.
What it costs
| Seal leaking connections and plenum (accessible attic) | $500–$1,500 | Mastic and tape at boots, joints, plenum |
| Replace individual runs (per run) | $250–$600 | Crushed, torn, or disconnected sections |
| Partial replacement (several runs + plenum) | $1,500–$4,000 | When the trunk is fine but branches failed |
| Full duct replacement, 1,500–2,500 sq ft single story | $5,000–$9,000 | New insulated flex or rigid trunk, new boots |
| Two-story or difficult attic access | Higher | Quoted on site |
Market ranges for the East Valley, pending on-site inspection. Your written quote is firm before work starts.
Signs your ducts are the problem
- One or two rooms always hot, even with a healthy AC
- Dusty house shortly after cleaning
- A system that runs constantly in summer. See AC runs constantly
- High SRP or APS bills compared with neighbors in similar homes
- Visible sagging, crushed or disconnected flex duct in the attic
- Homes from the 1970s and 1980s with original ductwork
Repair, seal, or replace?
Seal if the ducts are in decent shape and the leaks are at the connections. That's most homes built after 2000.
Repair runs if a few sections are crushed or torn, often from attic work, solar installs, or pests.
Replace if the ducts are original to a '70s or '80s house, the insulation is crumbling, or the system was never sized right. It's the right time to do it when you're replacing the AC, because the crew and attic access are already there.
Why it matters at replacement
A new high-efficiency system on leaky, undersized ducts won't deliver its rated efficiency. If we're quoting a new system, we'll look at the ducts and tell you whether they're the weak link. If they're fine, we'll say so and leave them alone.
Rebates
APS and SRP have offered duct sealing and duct test rebates through participating contractors in some years. Programs change; see APS & SRP rebates in 2026.
Questions people ask
How much does it cost to replace ductwork in Phoenix?+
Full replacement on a typical single-story East Valley home runs about $5,000 to $9,000. Sealing runs $500 to $1,500, and individual runs $250 to $600 each.
How long does ductwork last in Arizona?+
Flex duct in a Phoenix attic often lasts 15 to 25 years. Heat breaks down the insulation and jackets faster than in milder climates.
Should I replace ducts when I replace my AC?+
If the ducts are original to an older home or failing, yes. It's the cheapest time to do it. If they test fine, no.