Whole-home duct cleaning
Dryer vent cleaning
Camera inspection
Sanitizing & deodorizingWhole-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.
Trusted Duct Sealing for Dallas Homeowners
Leaky ducts in a Dallas home don’t just waste conditioned air. They pull attic heat into your living space in August, drag dust and fiberglass particles through your supply vents, and force your HVAC system to run harder than it should. That’s the problem duct sealing solves. Hollis Air Duct Dallas has handled Duct Sealing in Dallas since 2004, led by Roy Castellanos. We arrive inside the quoted window, write the price down before we touch anything, and back the work with our 365-Day Done Right Promise. Call (361) 309-6223 and you’ll talk to a live person, not a voicemail tree.
We use professional-grade equipment from Rotobrush, Nikro, and Abatement Technologies, and we explain what we’re doing in plain English before we start. Every job gets a written price, a written guarantee, and a clean work site when we leave.
Duct Insulation
Duct Insulation is the thermal jacket around your ductwork that prevents conditioned air from losing its temperature before it reaches the rooms you’re trying to heat or cool. In Dallas, where attics routinely hit 130 degrees in July, uninsulated or poorly insulated ducts can lose 20 to 30 percent of your cooling output before a single degree reaches your living room. When ducts run through unconditioned spaces like attics, crawl spaces, or garages, insulation isn’t optional; it’s the difference between paying to cool your house and paying to cool the underside of your roof. Hollis Air Duct Dallas inspects existing duct insulation for compression, moisture damage, and gaps, then repairs or replaces it with materials rated for North Texas conditions. Typical duct insulation work in Dallas runs $400 to $1,800 depending on how much linear footage needs attention and whether we’re replacing existing wrap or insulating previously bare ducts.
Attic Duct Wrap Replacement
Heat breaks down old fiberglass wrap over time, especially in Dallas attics where temperatures swing from below freezing to over 120 degrees in the same year. We remove the degraded material, seal the duct surface, and install new insulation with a vapor barrier that stands up to humidity and heat. The goal is an R-value that actually matches what your system was designed for.
Uninsulated Duct Remediation
Some older Dallas homes, particularly those built before the 1990s in areas like Lake Highlands and Oak Lawn, have bare sheet metal ducts running through unconditioned attics. These ducts sweat, rust, and leak temperature through the metal itself. We wrap them properly so the air leaving your blower is close to the same temperature when it reaches the register.
Styles & brands we work with
HVAC Duct Sealing
HVAC Duct Sealing is the process of closing every hole, seam, and disconnected joint in your ductwork so that conditioned air actually reaches the rooms it’s supposed to reach. Over time, tape dries out, connections loosen, and the pressure from your blower pushes air through any gap it can find. In a typical Dallas home, 15 to 25 percent of conditioned air escapes through duct leaks, which means you’re paying for air you never feel. Hollis Air Duct Dallas locates those leaks and seals them with mastic and appropriate mechanical fasteners, not duct tape, which fails within a few years. HVAC duct sealing in Dallas generally costs $600 to $2,400 depending on system size, accessibility, and the number of leaks we find during inspection.
Supply and Return Leak Sealing
Supply-side leaks push cooled air into your attic before it reaches your vents. Return-side leaks pull hot attic air into your system before it hits the coil. Both are common in Dallas homes, and both force your AC to work harder while making some rooms consistently warmer than others. We seal both sides of the system.
Mastic Application Standards
Mastic is a thick, paste-like sealant that hardens into a flexible, airtight barrier. Unlike tape, it doesn’t peel in heat or dry out in a year. Our technicians apply it at every accessible seam and joint, then test the system pressure to confirm the improvement, because reading the result matters more than claiming it.
Duct Repair
Duct Repair addresses damaged ductwork: crushed sections, disconnected runs, rusted collars, pest damage, and sagging flex duct that has pulled loose from its connections. In Dallas, we regularly see duct runs in attics that have been stepped on by cable installers, chewed by squirrels, or simply separated from age and heat exposure. A crushed section of flex duct can cut airflow to a bedroom by half, while a disconnected return can pull insulation particles and attic dust directly into your air stream. Hollis Air Duct Dallas repairs or replaces damaged duct sections using professional-grade materials and seals every connection to code. Duct repair in Dallas typically costs $350 to $1,900 depending on how much ductwork needs replacement and whether sections are accessible from the attic or require more involved access work.
Crushed and Collapsed Duct Replacement
When a duct is crushed flat, no amount of sealing fixes it. The damaged section needs to come out and a properly sized replacement needs to go in. We match the replacement duct to your system’s airflow requirements, not just whatever’s cheapest on the shelf, because undersized duct reduces efficiency and shortens equipment life.
Disconnected Joint Repair
Heat and vibration work duct connections loose over time. A separated joint can dump a room’s worth of conditioned air into your attic for months before you notice the room getting warmer. We reconnect, seal, and test every joint we touch, including the ones upstream and downstream of the apparent failure.
Air Duct Sealing
Air Duct Sealing focuses on the interior air path: making sure the air moving through your ducts travels only where the registers allow it to go. This matters as much for air quality as for efficiency. When return ducts draw from the attic, they pull in whatever’s up there: fiberglass particles, dust, rat droppings, old insulation. Sealing the returns closes that pathway. When supply ducts leak into wall cavities, the air you paid to condition ends up behind drywall while your rooms stay warm. Hollis Air Duct Dallas inspects the full air path and seals the leaks that actually move the needle on your utility bill and your comfort. Air duct sealing in Dallas typically runs $500 to $2,200 for a standard single-family home, depending on duct configuration and access.
Return Side Air Duct Sealing
Most homeowners never look at their return ducts. That’s where we often find the biggest problems: separated flex duct pulling attic air, loose plenum connections, and gaps where the return meets the air handler. Sealing the return side protects your indoor air quality and improves system pressure balance.
Plenum and Boot Sealing
The plenum is the metal or fiberboard box that distributes air from the blower. The boots are the fittings that connect ductwork to your floor or ceiling registers. Both are common leak points, especially in older Dallas homes where the original connections were never properly sealed in the first place. We seal them at every accessible point.
Duct Sealing Services
Duct Sealing Services covers everything from single-leak repairs to full-system sealing for homes throughout the Dallas area, including Lake Highlands, Highland Park, Oak Lawn, and the surrounding suburbs like Duct Sealing in Garland. Every job starts the same way: a thorough inspection of the accessible ductwork, a written list of what we found, and a flat price for the work before we begin. No per-vent pricing games, no price that changes when the technician gets a closer look. Hollis Air Duct Dallas provides duct sealing services with equipment from Nikro and Abatement Technologies, which means we can test airflow before and after the work to verify the improvement. Full-system duct sealing service in Dallas generally costs $800 to $2,800 depending on home size and duct complexity.
Whole-Home Duct Sealing
For homes with older systems or multiple problem areas, a whole-home approach gives you the best return. We seal every accessible seam, joint, and connection in the system, then test the results. The difference shows up in more consistent room temperatures and a lower cooling bill during the Dallas summer.
Post-Renovation Duct Sealing
Remodels stir up dust and often leave ducts disconnected, crushed, or poorly reconnected. If you’ve had work done recently in Lake Highlands, Highland Park, or Duct Sealing - Richardson and your HVAC hasn’t felt right since, a post-renovation sealing inspection finds what the contractors left behind and puts it right.
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.
Brands We Service
Our technicians work on all major duct and HVAC equipment brands. We’ve sealed and repaired ducts connected to systems from every major manufacturer found in Dallas homes, and we don’t play favorites. What matters is the ductwork configuration and the condition of the connections, not the sticker on the air handler.
We keep professional-grade products from Honeywell and Aprilaire on hand for filtration and air quality work that often goes hand-in-hand with duct sealing. If your system has existing Aprilaire media filters or a Honeywell electronic air cleaner, our team knows how they integrate with the ductwork we’re sealing. Whether you have a top-of-the-line system or a builder-grade unit, we can help with the sealing work your ducts need to perform properly.
See the difference
Before
After
Before
After
Before
AfterSigns You Need a Pro Right Now
- Rooms stay warm no matter how low you set the thermostat. If one bedroom is always 8 degrees warmer than the rest of the house, you likely have a supply duct leak or a crushed run feeding that room. The fix is usually straightforward once we find the failure point.
- Your cooling bill keeps climbing while your comfort stays flat. A duct system leaking 20 percent of its output forces your AC to run longer to hit the same temperature. That extra runtime shows up directly on your Reliant or TXU bill, and it only gets worse as leaks widen.
- You see dust or insulation particles blowing from your vents. Return-side leaks pull attic air into your system. That means whatever is in your attic, including fiberglass particles and dust, is being blown into your living space. Sealing the returns stops that path at the source.
- Your attic feels cool while the house feels warm. If you go up to the attic in August and it feels like a meat locker up there while your living room is stuffy, your supply ducts are dumping conditioned air into the attic. That’s money leaking through your ceiling.
- Rooms smell musty or like the attic after the AC runs. Duct leaks pull unfiltered air through gaps and cracks. What you’re smelling is un-conditioned, unfiltered air entering the air path. Sealing those leaks and checking the duct insulation solves it.
Our Process, Step by Step
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Inspection and airflow testing. We start by examining every accessible section of ductwork, checking connections, looking for crushed or sagging runs, and measuring airflow at key registers. This tells us where the real problems are, not just where the visible ones are.
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Written findings and a flat price. Before any work starts, we put the scope of work and the total price in writing. That price does not change when we get into the attic. No add-ons, no “while we’re here” surprises, no moving targets.
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Sealing and repair work. We apply mastic at every accessible seam and connection, repair or replace damaged duct sections, and re-wrap insulation where heat has degraded it. Every job uses materials rated for Dallas attic conditions.
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Post-work verification. After sealing, we re-test airflow to confirm the improvement. If the numbers don’t show meaningful gains, we keep working until they do. Verification is part of the job, not an upgrade.
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Cleanup and walkthrough. We leave the site cleaner than we found it. That means no debris in the attic, no dust in the hallway, and no mystery materials left in your driveway. Then we walk you through what we did and show you the before-and-after measurements.
How Much Does Duct Sealing Cost in Dallas?
A typical duct sealing job in Dallas runs $600 to $2,400, with most single-family homes landing between $900 and $1,600. The spread depends on several factors. Home size matters: a 3,000-square-foot home in Highland Park has more linear feet of ductwork than a 1,400-square-foot home in Sachse or DeSoto Duct Sealing jobs. Accessibility matters too: ducts in a tall attic with tricky access take longer than ducts in a crawl space with easy reach. The number of leaks we find during inspection is the biggest variable, which is why we inspect before we quote, not after.
What affects the price most is whether the job is sealing only or sealing plus repair. Sealing existing joints is less expensive than replacing crushed or disconnected sections. If your ducts are relatively intact but leaky, the cost stays lower. If they’ve been stepped on, chewed through, or badly installed, the repair portion adds to the total. You’ll know exactly what’s included before we begin, because the price is written down and it doesn’t move.
To avoid overpaying, watch for companies that quote a low teaser price over the phone and then “discover” problems once they’re inside. That’s a sales technique, not an inspection. Our estimate comes from a real inspection of your actual ductwork, and the number we write down is the number you pay. A free estimate from Hollis Air Duct Dallas includes the inspection, the written findings, and the flat price. Call (361) 309-6223 to schedule one.
Our Service Area Near Dallas
Hollis Air Duct Dallas serves homeowners across the Dallas metro area, including Highland Park, Lake Highlands, Oak Lawn, Sachse, Murphy, Rowlett, and the surrounding communities. We also provide Duct Sealing in Garland and Duct Sealing in Richardson for homeowners across the northeast metro. If you’re in DeSoto, Red Oak, or Heath, give us a call; our service area extends throughout Dallas County and the nearby suburbs. Most inspections can be scheduled within a few business days, and we arrive inside the quoted window every time. Check our home page for more on who we are and how we work.
Serving Dallas, TX - Our Local Coverage Area
We’re based in the Dallas area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
Frequently Asked Questions About Duct Sealing in Dallas
Duct sealing is the process of closing air leaks in your ductwork so that conditioned air reaches the rooms it’s meant to reach, not your attic or wall cavities. It involves applying mastic sealant at seams and joints, repairing disconnected sections, and sometimes adding or replacing duct insulation. In Dallas, where cooling season runs from April through October, properly sealed ducts directly reduce your energy waste and improve room-to-room temperature consistency.
A standard duct sealing job in Dallas takes between 4 and 8 hours for most single-family homes. More extensive jobs involving multiple duct repairs or full replacement of damaged sections can take a full day. We give you a clear time estimate in writing before we start, and we honor it.
Most Dallas homeowners pay between $600 and $2,400 for duct sealing, with the average job landing around $1,200. The final price depends on home size, duct accessibility, and the number of leaks found during inspection. You’ll receive a written price before any work starts, and that price doesn’t change. Call (361) 309-6223 for an exact quote; estimates are free.
Yes. Our technicians work on duct systems connected to every major HVAC brand found in Dallas homes, and we don’t limit our work by manufacturer. Where it matters, we keep Honeywell and Aprilaire filtration products on hand for air quality work that integrates with the sealing job. Ductwork is the part of your system we specialize in, regardless of the sticker on your air handler.
We answer the phone with a live person 24 hours a day, 7 days a week, so you can reach us whenever the problem shows itself. Most duct sealing jobs are scheduled within a few business days, but if you’ve got a disconnected return pulling attic air into your home, we’ll get you scheduled as fast as our calendar permits. Call (361) 309-6223 and tell us what’s happening; we’ll give you a straight answer.
Every duct sealing job from Hollis Air Duct Dallas is covered by our 365-Day Done Right Promise, which is a written guarantee, not a verbal one. If the work fails within a year, we come back and make it right at no charge, including a free second visit. That’s the entire point of the guarantee: if it’s not done right, we’re not done.
You don’t need to do much. Clear a path to your attic access or crawl space entry, and keep pets in a separate room while our technicians are working. We bring drop cloths and protective gear, and we leave the site clean when the job is done. Roy Castellanos and our technicians arrive in uniform, background-checked, and ready to explain what they found and what they’re doing about it.
Schedule Your Duct Sealing Service in Dallas Today
Call (361) 309-6223 to schedule a free duct sealing inspection in Dallas. You’ll get a real person on the phone, an appointment inside the quoted window, and a written price before any work begins. If you’ve noticed warm rooms, high cooling bills, or dust blowing from your vents, we’ll find the cause and fix it right. Our 365-Day Done Right Promise covers every job in writing for a full year.
Written by Roy Castellanos, Owner at Hollis Air Duct Dallas, serving Dallas since 2004.