Duct Repair & Sealing in Chicago - Tested First, Written Price Second

Trusted Duct Repair & Sealing for Chicago Homeowners

Most Chicago homes lose 20-40% of heated and cooled air through gaps, disconnected joints, and deteriorated ductwork before it ever reaches the registers. Duct Repair & Sealing in Chicago typically runs $450-$1,800 depending on whether we’re sealing accessible joints with mastic or replacing collapsed flex runs in a Park Ridge crawlspace. We’ve documented the inside of over 52,000 duct systems since 2013, and the photo record we deliver shows exactly where your air is going instead of where you want it.

Call (708) 683-3974

Our crews work across Chicago’s full climate range, from the humidity-driven expansion cycles that loosen tape seals in Hyde Park bungalows to the freeze-thaw stress that cracks metal seams in Norwood Park attics. Every job starts with a written price under Haven Standard Clause 1, and every duct run is photographed before and after. Call (708) 683-3974 for a free estimate with no obligation to schedule.

What Our Duct Repair & Sealing Service Includes

Duct Sealing

Duct sealing closes the gaps and leaks in your supply and return plenum - the main distribution box where your furnace or air handler connects to the branch lines - and along the trunk lines that carry air to each room. In Chicago’s older housing stock, particularly the balloon-frame construction common in Rogers Park and Andersonville, we’ve found that original ductwork often leaks at every joint where decades of vibration have loosened the connections. Our crews use a combination of mastic sealant, metal-backed tape rated for HVAC applications, and mechanical fastening to create a permanent seal, then verify the improvement with a pressure test documented in your photo record.

Flex Duct Repair

Flex duct, the insulated flexible tubing common in additions and retrofits throughout Lincoln Park and Skokie, collapses when crushed by storage items in attics or deteriorates when the inner liner degrades from temperature cycling. We replace damaged flex runs with new R-8 insulated duct sized to the original Manual D specification, support it with proper straps at 4-foot intervals to prevent sagging, and seal every connection with approved clamps and mastic. The photo record shows the old collapsed section beside the new run so you can verify the work without climbing into the attic yourself.

Metal Duct Repair

Galvanized steel ductwork, still standard in most Chicago homes built before 1990, develops rust at low points where condensation collects and separates at seams where the original sealant has hardened. In homes near the lakefront, we’ve documented accelerated corrosion from the higher humidity that penetrates attic and crawlspace environments. Our metal duct repair includes cutting out deteriorated sections, fabricating replacement pieces from 26-gauge galvanized sheet metal, and sealing with mastic and drive cleats rather than relying on tape alone. Every repair is pressure-tested before we leave.

Duct Insulation

Uninsulated or poorly insulated ductwork in unconditioned spaces - attics, crawlspaces, and garages throughout Chicago’s bungalow belt - loses substantial thermal energy and creates condensation that feeds mold growth. We install R-6 or R-8 fiberglass duct wrap with a vapor barrier, secured with metal fasteners and sealed at every seam, to bring your system up to current Illinois energy code requirements. In a recent job in Portage Park, the temperature differential across an insulated trunk line dropped from 14 degrees to 3 degrees, a change we documented with thermal imaging included in the photo record.

Mastic Sealant Application

Mastic is a water-based, fiber-reinforced compound that remains flexible after curing, making it the preferred sealant for joints that experience thermal movement. Unlike foil tape, which can loosen when the adhesive degrades, mastic forms a permanent bond to metal, fiberglass, and flex duct materials. Our crews apply mastic with a brush or caulking gun to every accessible joint, then brush it into a smooth fillet that won’t trap dust or obstruct airflow. The photo record shows the applied mastic while it’s still wet, so you can see complete coverage rather than guessing what happened behind the walls.

Air Leak Repair

Air leaks occur at the interface between ductwork and the building envelope - where supply registers meet drywall, where return air pathways draw from wall cavities, and where penetrations for plumbing and electrical create unintended pathways. In Chicago’s high-rise conversions and vintage courtyard buildings, we’ve found that “ductwork” sometimes consists of building cavities never intended to carry air, leaking into interstitial spaces and between units. Our air leak repair includes sealing these pathways with fire-rated foam and mastic, installing proper return air ducting where needed, and verifying with a blower door test when the scope warrants.

Brands We Service for Duct Repair & Sealing

We’ve worked on duct systems connected to every major HVAC brand installed in Chicagoland since the 1970s. Honeywell zoning systems, common in North Shore homes with multiple thermostats, require careful sealing at the zone dampers to prevent bypass airflow that defeats the temperature control - we’ve serviced hundreds of these installations and stock replacement dampers and actuator motors. Aprilaire whole-home humidifiers and dehumidifiers, frequently added to high-efficiency furnaces in Hinsdale and Oak Park, need sealed bypass ducts and proper drainage that our crews verify as part of any repair scope. Rotobrush equipment is what we use for the negative-pressure extraction and agitation that precedes sealing work, so we know exactly how their brush systems interact with existing duct conditions.

Whether your system was installed by a major Chicago contractor like Four Seasons or a neighborhood shop that’s been gone for twenty years, we can repair and seal it. We don’t require that you know the brand before calling - our diagnostic process identifies the components and documents them in the written scope. If you have Honeywell, Aprilaire, or any other make, we can help.

Before

After

Signs You Need Duct Repair & Sealing Right Now

• Uneven temperatures from room to room. When a bedroom stays 10 degrees colder than the living room despite the register being open, the duct serving that room has likely separated at a joint or collapsed internally. We see this constantly in Chicago two-flats where flex duct was run through unconditioned attic spaces without proper support.
• Dust accumulation immediately after cleaning. If you’ve dusted thoroughly and find a new layer within 48 hours, your return ductwork may be pulling air from a crawlspace, attic, or wall cavity instead of from the conditioned space. The photo record we deliver shows exactly where this unfiltered air is entering the system.
• Utility bills that spike without explanation. A sudden 20-30% increase in heating or cooling costs, especially after a mild shoulder season, often indicates a major duct leak that’s dumping conditioned air into an unconditioned space. We’ve found disconnected trunk lines in Skokie basements that were blowing $400 a month into the dirt.
• Whistling or rushing air sounds. High-velocity noise at registers usually means the duct is undersized for the airflow, but it can also signal a partial collapse or sharp bend that’s forcing air through a restricted opening. Either condition increases static pressure and strains your blower motor.
• Musty odors when the system runs. Smells that intensify when the fan cycles on suggest moisture intrusion through duct leaks, creating mold growth on the duct interior or in the surrounding building cavity. This is particularly common in Chicago’s lakefront neighborhoods where summer humidity runs high and winter stack effect draws that moisture into wall assemblies.

Our Duct Repair & Sealing Process - Step by Step

1. 1
   Visual and photographic documentation of every accessible duct run. Before we touch anything, we photograph the condition of your plenum, trunk lines, branch ducts, and register connections. This baseline becomes page one of your documented photo record and protects both parties from disputes about pre-existing conditions.
2. 2
   Pressure testing to quantify leakage. We seal the registers temporarily and pressurize the duct system to measure total leakage in CFM25 - cubic feet per minute at 25 Pascals of pressure. This number, typically 15-30% of total airflow in Chicago homes we test, gives us a measurable target for improvement and a way to verify our work.
3. 3
   Written scope and price delivered before any work begins. Haven Standard Clause 1 requires that you receive a written price for the exact work proposed, with line items for materials, labor, and any contingencies. No work starts until you’ve approved this document. “Call for a quote” does not exist in our process.
4. 4
   Repair and sealing with trade-verified methods. Our crews use mastic, mechanical fasteners, and replacement duct sections as specified in the scope. Every joint is accessible for future inspection, and we never bury a connection behind drywall without photographic documentation. Equipment on the truck includes Rotobrush negative-pressure systems and Nikro HEPA vacuums for containment during cutting operations.
5. 5
   Post-repair pressure test and photo record delivery. We retest to verify leakage reduction, typically targeting 5% or less of total airflow. The final photo record, including before images, during-work documentation, and after verification, is delivered as a standard job deliverable - not an extra, not available only on request.

How Much Does Duct Repair & Sealing Cost in Chicago?

Duct Repair & Sealing Near Chicago - Our Service Area

We repair and seal ductwork across the full Chicago metro, from the lakefront high-rises of the Gold Coast to the ranch-style homes of Orland Park and the mid-century splits of Glenview. Typical scheduling runs 2-4 business days for standard repairs, with emergency response available for complete system failures during extreme weather. Our crews are familiar with the specific construction types common to each area: balloon-frame bungalows in Berwyn, post-war tract housing in Des Plaines, and new construction flex-duct systems in Downers Grove. We also provide Duct Repair & Sealing in Oak Lawn and Duct Repair & Sealing in Hinsdale with the same written pricing and documented photo record standard.

Frequently Asked Questions - Duct Repair & Sealing in Chicago

Schedule Your Duct Repair & Sealing Service in Chicago Today

Call (708) 683-3974 to speak with a live person and schedule your free estimate. You’ll receive a written price before any work starts, a documented photo record of every duct run, and the 365-Day Done Right Promise backed in writing. No coupons, no urgency theatre, no surprises - just accountable work you can verify.

Written by Tomas Reyes, Owner at CleanRun Duct Repair & Cleaning, serving Chicago since 2013.