Fast, Reliable Duct Repair & Sealing Across Chicago
Duct repair and sealing in Chicago typically costs $280-$650 for most residential jobs, with larger three-flat trunk repairs running $800-$1,400. We’re usually on-site within 24 hours across the city, and most repairs finish in a single visit. Call (844) 685-6342 for a free estimate with upfront pricing before any work begins.
We’ve been serving Chicago homeowners since 1984, and we know the city’s heating systems like we know the lakefront in winter. From Pilsen brick two-flats to Loop loft conversions, Chicago buildings present ductwork challenges you won’t find in suburban markets. Our technicians carry the equipment to handle century-old galvanized trunks, asbestos-wrapped plenums, and the patchwork sealing jobs left behind by decades of quick fixes. We don’t do bait coupons or scare tactics. One honest price, shown before we start. That’s how we’ve operated for 42 years.
Why Bellows Air Duct & Vent Co. Is Chicago’s Preferred Duct Repair & Sealing Company
Ray Castillo built this company on a simple standard: the job gets done right, or we come back and make it right. No paperwork, no arguing. That 90-Day Done Right Promise is stamped on every invoice we write in Chicago, and it’s why homeowners in Bridgeport, Pilsen, and the Near North Side call us back when something else needs attention.
Our reviews from Chicago customers consistently mention the same things: we show up when we say we will, we explain what’s actually wrong before touching a tool, and the price on the phone matches the price on the bill. Calls are answered by a live person, 24 hours a day. Not a voicemail tree. Not an app.
We understand Chicago’s heating season, that stretch from October through April when furnaces in older buildings run almost continuously against sub-zero wind chills off Lake Michigan. That kind of load exposes every weak seam, every failed tape joint, every flex duct pulled loose by decades of vibration. Our Duct Repair & Sealing team knows what to look for in these conditions because we’ve worked through 42 of Chicago’s winters.
Most Chicago jobs complete in one visit. Our technicians are background-checked, uniformed, and equipped with Rotobrush and Abatement Technologies gear sized for residential and light commercial ductwork. Before we leave, we camera-inspect the repair so you see the result, not just hear about it.
Our Duct Repair & Sealing Services in Chicago
Duct Sealing
Sealing is where most Chicago buildings need help. Those original gravity-furnace trunks in 60607 and 60608 were never designed for forced-air pressure. When gas systems were retrofitted in the 1950s through 1970s, contractors often extended existing ductwork without proper sealing at branch takeoffs or plenum connections. We find significant air loss at these points in nearly every older building we inspect. Our crew uses foil-backed butyl tape and professional-grade mastic to restore airtightness at joints, seams, and register boots. Camera verification before and after documents the improvement.
Mastic Sealant Application
Mastic is the right choice for old metal ducts with uneven surfaces or oily dust residues that tape won’t adhere to. In Chicago’s pre-1930 buildings, we regularly apply flexible mastic along longitudinal trunk seams and around plenum connections where thermal cycling has cracked older sealant. The product we use is rated for the temperature swings these systems see, from summer humidity to winter supply air at 140°F. A typical mastic sealing job in Chicago runs $340-$580 for a single-family or two-flat system.
Metal Duct Repair
Original galvanized trunk ducts in Chicago’s three-flats can last a century, but they don’t last without attention. Seam failures along the bottom of horizontal runs are common where condensation and debris have corroded the metal or where the original longitudinal lock has simply fatigued. We repair these with mechanical reinforcement and sealing, preserving the trunk rather than replacing it. In Bridgeport and Pilsen, preserving that original trunk matters. Replacement would require asbestos abatement, structural modification, and costs that start at $2,500. Repair is usually $650-$1,100.
Duct Insulation
Chicago’s summer humidity off Lake Michigan creates condensation inside poorly insulated basement and sub-floor duct runs. We’ve found mold contamination in uninsulated supply trunks in Near North Side basements and West Town crawl spaces. We install fiberglass duct wrap with proper vapor barrier, or closed-cell foam where space is tight. Insulation also reduces the heat loss that makes upper-floor vents barely lukewarm in January, a complaint we hear constantly from owners of Chicago’s older brick buildings.
What happens when you call
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A real person answersNo phone trees - you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Chicago
We stock parts and specify equipment from Rotobrush, Abatement Technologies, and Aprilaire, the same brands serious HVAC contractors use when they’re not cutting corners. For Chicago’s older housing stock, that matters. A residential duct vac won’t clear compacted dust from a 16-inch gravity-furnace trunk. We bring the right equipment for the building, not the easiest tool for the truck. Parts availability in Chicago is solid for these brands, so we don’t leave you waiting while something ships from out of state. Most repairs are same-day because we planned for what your building actually needs.
Common Duct Repair & Sealing Problems We See in Chicago Homes
- Failed mastic and tape along basement trunk seams. Chicago’s heating season runs six months with furnaces cycling hard. The thermal expansion at the furnace plenum eventually cracks old sealant. We see this most in buildings where the original 1950s or 1970s retrofit sealant has never been refreshed.
- Improper flex duct connections at branch takeoffs. Retrofitted forced-air systems in two-flats and three-flats often have flex duct jammed onto takeoffs with inadequate mechanical fastening. Air leaks here pull debris from basements and wall cavities into the system, and they waste the heat you’re paying for through February.
- Asbestos insulation on original ducts. The gray corrugated pipe wrap on those 1920s trunks is not removed by our crew. We photograph it, disclose its condition to the homeowner, and seal or cover professionally without disturbing the material. Untrained technicians who tear into this create an abatement situation that costs thousands.
- Condensation and mold in uninsulated sub-floor runs. Summer humidity in Chicago hits basement ductwork hard. We’ve opened systems in Cicero and Belmont Cragin where the bottom of galvanized trunks were lined with mold growth from years of condensation dripping off uninsulated supply air.
Pricing for Duct Repair & Sealing in Chicago, IL
We’re upfront about numbers because we’ve seen what bait-and-switch pricing does to trust. Here’s what duct repair and sealing costs in Chicago’s market:
| Service | Typical Range in Chicago |
|---|---|
| Single register boot sealing (1-2 boots) | $180-$260 |
| Branch duct sealing (flex or metal) | $280-$450 |
| Mastic sealing of basement trunk seams | $340-$580 |
| Metal trunk repair with reinforcement | $650-$1,100 |
| Large three-flat gravity-furnace trunk repair | $800-$1,400 |
| Duct insulation (basement trunk wrap) | $420-$780 |
What moves the price: accessibility of the ductwork, extent of asbestos wrap requiring documentation, whether we can reach the seam without demolition, and the condition of the existing metal. We inspect with a camera before quoting, so the number you get is the number on the invoice. No surprises on the bill. We also honor our standing offers: $50 off any repair over $250, free second opinion on any written estimate, and a permanent 5% senior and veteran discount.
Call (844) 685-6342 for your free estimate.
We Also Serve Cities Near Chicago
Our service area extends across the metro, including Chicago neighborhoods like Near North Side and West Town, plus Cicero and Belmont Cragin. Same response standards, same upfront pricing, same 90-Day Done Right Promise. If you’re unsure whether we cover your address, call and ask. A live person will answer.
Serving Chicago, IL - Our Local Coverage Area
We’re based in the Chicago area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs - Duct Repair & Sealing in Chicago
We do not remove asbestos-containing insulation. Our protocol is to photograph the material, disclose its condition to you in writing, and complete our sealing work without disturbing the wrap. If removal is necessary for other reasons, we refer you to a licensed abatement contractor. This protects your health, your liability, and your wallet. Call (844) 685-6342 to schedule an inspection - estimates are free.
Yes, this is one of the most common complaints we hear in Chicago’s pre-1930 buildings. Leaky basement trunk seams and failed branch connections bleed heated air into unconditioned spaces before it reaches the second or third floor. Sealing those leaks typically restores adequate airflow without replacing equipment. We’ve solved this exact problem in dozens of Near North Side and West Town two-flats. Call (844) 685-6342 for a camera inspection.
Yes, we specialize in preserving these original trunks rather than replacing them. We recently sealed a 100-year-old brick three-flat in Bridgeport where the original gravity-furnace trunk had a longitudinal seam failure along its bottom, creating a six-foot gap. Using Rotobrush tools and mastic sealant, we reinforced the seam with foil-backed butyl tape and applied flexible mastic to restore airtightness, all while documenting asbestos wrap for the homeowner’s disclosure. Repair preserved the system and avoided a $3,000+ replacement project.
Water-based flexible mastic is our standard for Chicago’s older galvanized ducts. It adheres to surfaces that tape won’t grip, fills irregular gaps, and remains flexible through the thermal cycling these systems experience. For high-vibration areas near the furnace plenum, we add mechanical reinforcement with foil-backed butyl tape before mastic application. The combination lasts. Call (844) 685-6342 and we’ll show you exactly what we mean on your system.
Repair it, unless the metal itself is perforated with rust holes or structurally compromised. Original 12-16 inch galvanized trunks are robust, and replacement in Chicago’s three-flats triggers asbestos abatement, permit complications, and structural modifications that start at $2,500. Most seam failures, loose connections, and even localized corrosion are repairable for $650-$1,100. We’ll camera-inspect and give you an honest assessment. No scare tactics. Call (844) 685-6342 for a free second opinion if another contractor has told you replacement is your only option.
Written by Ray Castillo, Owner at Bellows Air Duct & Vent Co., serving Chicago since 1984.