Whole-system duct and dryer vent check with before-and-after photos - you see exactly what came out of your vents
That "$99 whole-house special" is a bait ad - the real number appears once they are in your hallway, or the "clean" is a shop-vac at the register. We photograph the inside of your ducts before and after instead.
Fast, Reliable Duct Sealing Across Orange
Duct sealing in Orange typically runs $1,200 – $2,800 for a whole-home job, depending on access, duct condition, and whether we’re working with original sheet metal or modern flex duct. Most Orange homeowners see lower utility bills and more even room temperatures within the first billing cycle after sealing. Call (361) 326-5060 for a free written estimate.
We’ve been driving to Orange since our Los Angeles office first opened scheduling for this market. Our crews know the difference between a 1920s bungalow off Chapman Avenue and a 1970s two-story near Santiago Canyon Road. That matters because the ductwork we’re sealing is completely different, and the approach has to be too. In Old Towne Orange, we’re often working with gravity furnace remnants and unlined sheet metal that’s pushing a century old. In east Orange ranch tracts, it’s undersized flex duct from the 1960s that’s crushed in attics or disconnected at the plenum. We don’t guess. We inspect with a camera, write the price down, and seal what we find.
Our Duct Sealing team serves all of Orange, from the historic core to the newer developments near the 55 and 91 freeways. Dispatch and scheduling are coordinated from our Los Angeles office, but the crews on your driveway live and work in this area. They know the Santa Ana wind dust that gets pulled into leaky return ducts every September. They know which east Orange neighborhoods have original asbestos-wrapped duct insulation that can’t be disturbed the standard way. That local knowledge keeps the job clean and keeps your home’s character intact.
Why Hollis Air Duct Cleaning Is Orange’s Preferred Duct Sealing Company
Hollis Air Duct Cleaning has been part of the Garrison Partners family since 2004. In Orange, our reputation is built on showing up inside the window, pricing in writing before we touch anything, and leaving the site clean. That’s The Garrison Standard, and it’s how every Hollis location operates, independently owned and accountable.
Our technicians are background-checked and uniformed. You know who’s walking into your home before they arrive. And our phones are answered by a live person 24 hours a day, 7 days a week. No voicemail loops, no callback queues, no waiting until Monday to schedule.
Every duct sealing job in Orange carries our 365-Day Done Right Promise. If the seal fails or the leak returns within a year, we come back and make it right at no charge, including a free second visit. That’s written on every invoice, not implied. We’ve found that homeowners in Orange, especially those in historic districts, value that kind of accountability because they’ve dealt with contractors who disappear after the check clears.
We recently sealed leaky supply and return ducts at a 1925 Spanish Colonial Revival bungalow off North Glassell Street in Old Towne Orange. After a camera inspection revealed disconnected runs and crushed flex duct in the attic, we used mastic and mesh to seal the joints without cutting into the original plaster walls, then verified with a blower door test that leakage dropped significantly. The homeowner noticed better airflow and no more attic dust smell on startup.
Duct Insulation in Orange
Duct Insulation in Orange is often the missing piece after sealing, especially in homes with original uninsulated sheet metal running through hot attics or damp crawlspaces. Sealing stops the air leak; insulation stops the thermal loss. In Orange’s climate, where attic temperatures can hit 140°F in July and winter rains introduce moisture into crawlspace runs, uninsulated ducts waste serious energy and can grow musty.
A typical Duct Insulation job in Orange runs $800 – $1,800, depending on linear feet of accessible duct, whether we’re wrapping existing metal or replacing degraded fiberglass, and whether the attic or crawlspace allows safe technician access. We use professional-grade materials, including Guardsman insulation products, and we never bury a duct in insulation until the leaks are sealed first. Insulating a leaky duct just hides the problem.
When Insulation Beats Replacement
Many east Orange ranch homes have flex duct from the 1960s or 1970s that’s intact but thin. If the duct isn’t crushed, disconnected, or asbestos-wrapped, we can often seal the joints and add an insulation sleeve for less than half the cost of full replacement. We write both options down and let you decide.
Moisture and Mold Concerns
Orange’s winter rains can soak attic or crawlspace insulation around ducts. We pull back the wrapper, check the liner for mold-like staining, and replace wet insulation before sealing. Trapping moisture against metal ductwork accelerates corrosion and sends musty air into your living space every time the blower cycles.
HVAC Duct Sealing in Orange
HVAC Duct Sealing in Orange is the core fix for rooms that never heat or cool evenly, utility bills that climb every summer, and dust that seems to reappear hours after cleaning. We seal supply and return ducts with mastic, mesh, and mechanical fasteners, then verify with a blower door or duct blaster test so you see the before-and-after numbers. In Orange, where many homes run original ductwork that’s undersized for modern HVAC loads, sealing is often the most cost-effective improvement short of full replacement.
Typical HVAC Duct Sealing in Orange costs $1,200 – $2,800 for a whole-home job. Single-zone repairs or partial sealing of accessible attic runs can run $400 – $900. The price is written down before we start, and it does not move at the door. No per-vent pricing, no add-ons once the van is in your driveway.
Historic Home Considerations
In Old Towne Orange’s historic district, sealing ducts can’t involve cutting into walls or modifying HVAC equipment without triggering historic preservation review, so we document existing conditions and seal from accessible points like attics and crawlspaces using non-invasive methods. We photograph everything before we start, seal what we can reach, and give you a written report for your records. Most leaks in these homes are at the plenum, in attic transitions, or where original gravity furnace ducts were adapted for forced air.
Modern Home Leak Patterns
In 1970s and 1980s two-story homes in southeast Orange, we commonly find disconnected flex duct at second-floor registers and leaky return plenums in garage-adjacent closets. These are accessible, sealable problems that don’t require wall demolition. We reach them from the attic or garage side, seal with mastic, and test.
Trusted Brands We Service in Orange
We seal and insulate ductwork connected to all major HVAC brands, and we carry sealing supplies and compatible insulation from Rotobrush, Nikro, and Guardsman on our Orange-area vans. That means most jobs don’t wait for parts. If your system uses specialized plenum fittings or uncommon duct dimensions, we source from our Los Angeles warehouse and schedule the seal for the next available window. We don’t start a job we can’t finish.
Common Duct Sealing Problems We See in Orange Homes
- Brittle asbestos-wrapped duct insulation in pre-1930 Old Towne homes crumbles during sealing attempts, requiring careful encapsulation rather than standard tape or mastic. We identify this material during camera inspection and adjust our approach before touching it.
- Uninsulated sheet-metal ducts in 1920s – 1950s homes expand and contract with Orange’s hot summers and wet winters, causing sealant to crack and disconnect at joints. We use flexible mastic compounds rated for thermal cycling, not rigid tapes that will split by next August.
- Undersized original ductwork in east Orange ranch tracts often has multiple disconnected runs that cannot be fully sealed without resizing or rerouting, leading to recurring leaks. We tell you honestly when sealing isn’t enough and write a replacement option alongside the seal estimate.
- Santa Ana wind dust infiltration through leaky return ducts is especially bad in September and October, when fine particles from the foothills get pulled into attic return plenums and distributed through the house. Sealing the return side often improves indoor dust more than the supply side.
Pricing for Duct Sealing in Orange, CA
Whole-home duct sealing in Orange typically costs $1,200 – $2,800. Partial sealing of accessible attic or crawlspace runs runs $400 – $900. Duct insulation added after sealing is $800 – $1,800. These are honest ranges for this market, not teaser prices that jump once we’re inside.
What moves the price: how much duct we can access without cutting walls, whether we’re sealing original sheet metal or modern flex duct, the condition of existing insulation that may need removal first, and whether we find asbestos-wrapped material requiring special handling. We inspect with a camera, write the exact price down, and get your approval before sealing anything. The price on the paper is the price on the invoice.
Every estimate is free. Call (361) 326-5060 to schedule.
We Also Serve Cities Near Orange
Our crews work throughout central Orange County. We regularly seal ducts in Orange as well as Santa Ana, Villa Park, Tustin, and Garden Grove. The same written pricing, same 365-Day Done Right Promise, same background-checked technicians at every stop.
Serving Orange, CA - Our Local Coverage Area
We’re based in the Orange 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 About Duct Sealing in Orange
Yes. We seal from accessible points, attics, and crawlspaces without cutting into original plaster walls or modifying visible HVAC equipment. We photograph existing conditions before starting and provide documentation for your records. If we encounter a leak that requires wall access, we flag it in writing and let you coordinate with the city’s historic preservation office before proceeding. Call (361) 326-5060 to discuss your specific home.
Uneven temperatures between rooms, rising summer utility bills despite normal usage, dust that returns within days of cleaning, and musty smells on first blower startup all point to leaks that cleaning won’t fix. In Orange’s older homes, we often find that decades of cleaning have left the ducts physically intact but leaking at every joint. Camera inspection shows the difference. We’ll show you.
Hot, dry summers cause thermal expansion that cracks rigid sealants, while winter rains introduce moisture into attic and crawlspace runs that degrades tape adhesives. We use mastic compounds rated for both conditions, and we schedule follow-up inspections during seasonal transitions for homes with severe leakage histories. The Santa Ana winds also pull fine dust into leaky returns, which sealing blocks at the source.
We do not disturb friable asbestos. If camera inspection reveals brittle, asbestos-wrapped duct insulation, we encapsulate rather than seal with standard mastic or tape, and we recommend a licensed abatement contractor for removal if the material is damaged. We document what we find, explain your options in writing, and only proceed with methods that don’t release fibers. Safety first, always.
We use Rotobrush rotary brush systems for pre-seal cleaning, Nikro negative-air machines for debris control during the job, and Guardsman insulation products for post-seal wrapping. For verification, we run blower door and duct blaster tests with calibrated equipment so you see the actual leakage reduction, not just our word. These are the same tools commercial crews use, maintained and calibrated per manufacturer spec.
Ready to stop heating your attic and start heating your living room? Call Hollis Air Duct Cleaning at (361) 326-5060 for a free written estimate on duct sealing in Orange. We’ll inspect with a camera, write the price down, and seal what needs sealing under our 365-Day Done Right Promise.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Orange and surrounding communities.




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