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.
Rotobrush Duct Sealing & Repair: The Dallas Owner’s Guide
Rotobrush-compatible duct sealing and repair in Dallas typically runs $340-$780 for a full system, depending on access and linear footage, and we stock the mastic, metal tape, and collar fittings for same-day completion on most residential jobs. Homeowners usually discover the problem when a room stays stubbornly hot in July despite the AC running nonstop, or when their energy bill spikes $80-$150 in a single summer month with no explanation. The camera doesn’t lie: we find separated joints, crushed flex runs, or dried mastic at the plenum (the main distribution box where air splits to each duct run) that was installed when the house was built and hasn’t been touched since.
Which Rotobrush Models This Applies To
Rotobrush builds three distinct equipment lines that touch duct sealing work, and the parts are not interchangeable between them. The Beast series (model numbers starting RB-9, including the RB-9.5 and RB-10) uses 8-inch diameter brush assemblies with keyed shafts; if your unit was manufactured before 2018, check the shaft collar for a single set-screw rather than the current splined design. The BrushBeast line (BB-8, BB-10) upgraded to a quick-release coupler that accepts standard 8-inch and 10-inch brushes but requires a different adapter for negative-pressure extraction ports. The aiR+ XP and aiR+ XP2 portable units use a 6-inch brush with a proprietary snap-ring retention; we’ve seen homeowners force-fit standard 6-inch aftermarket brushes and destroy the drive coupler in the process.
For duct sealing specifically, the Rotobrush negative-air machine (the HEPA-filtered vacuum unit that creates suction during sealant application) matters more than the brush model. The Nikro PM2000 and Rotobrush’s own portable HEPA units both interface with standard 4-inch and 6-inch collar fittings, but the hose diameter determines which mastic injection nozzles fit. We carry both OEM Rotobrush sealant collars and aftermarket equivalents from Abatement Technologies that match the thread pitch and gasket spec. The aftermarket collars save roughly $40-$60 per job and carry the same temperature rating to 200°F, which is what matters in a Dallas attic in August.
CleanRun Air Duct Cleaning Dallas is an independent service provider, not affiliated with Rotobrush. We stock parts for Lennox, Trane, and Carrier systems as well.
Signs Your Rotobrush Duct Sealing & Repair Is Failing

- Uneven room temperatures. One bedroom runs 6-8 degrees warmer than the thermostat reading while the living room freezes. This usually means a separated duct run above the ceiling, often at a flex-to-metal transition where the zip-tie or clamp has worked loose after years of vibration.
- Dust blowing from registers right after cleaning. If you had duct cleaning done six months ago and the registers are already coating your furniture, the vacuum may have dislodged debris without extracting it fully, or more likely, a gap in the return duct is pulling attic dust into the airflow. The camera shows fibrous insulation particles that only exist in attics, not inside finished walls.
- Whistling or roaring at specific registers. High-velocity noise means air is escaping before it reaches the vent, creating a pressure drop that pulls the remaining air through a smaller opening faster. We measure with a manometer: a 0.3-inch water column drop across a single register indicates a leak upstream.
- Musty smell that returns within days of any treatment. The antimicrobial spray hit the duct surface, but moisture is still entering through a gap in the plenum or a disconnected condensate line. In Dallas, where attic humidity hits 70% in shoulder seasons, that gap is a mold incubator.
- Energy bill climbing year over year with no rate change. Oncor’s rate structure hasn’t shifted, but your HVAC runtime has. A 15-20% leak in the supply duct means the system runs longer to hit the same temperature, and the compressor works harder. We see this pattern most in Preston Hollow and Lakewood homes built 1985-2005 with original flex duct.
Before
AfterReplacement Cost & What’s Included
| Scope | Typical Range | What’s Included |
|---|---|---|
| Single duct run repair (flex replacement, sealing) | $340-$520 | Parts, labor, photo documentation, 365-Day Done Right Promise |
| Partial system (3-5 runs, plenum reseal) | $580-$780 | All materials, negative-pressure verification test, written scope |
| Full system seal with Aeroseal or manual mastic | $1,800-$2,800 | Pre/post leakage test, register-by-register photo record, written warranty |
The range depends on three factors: attic access (a 140°F crawl in a Dallas August adds labor time), linear footage of damaged duct, and whether the plenum itself needs resealing or replacement. Metal plenums in older Dallas homes near the Design District often have original mastic that has dried to powder; we scrape to bare metal and reapply, then photograph the bead before it skins over. Haven Standard Clause 1 requires the written price before any work starts, and that price includes every fitting, every foot of tape, and every minute of labor. No per-vent add-ons, no “we found another problem” surprises.
The 365-Day Done Right Promise applies to all sealing work. If a joint we sealed separates or a collar we replaced fails within a year, we return and make it right. The promise is printed on the job record, not stated and forgotten.
DIY or Call Us?

Here’s what you can safely check yourself: remove a register and shine a flashlight up the duct. Look for disconnected flex, visible gaps at joints, or debris that shouldn’t be there. You can also feel for airflow at the plenum while the system runs, though attics in Dallas are not pleasant places to spend time in summer.
Here’s where DIY goes wrong. Duct sealing in a negative-pressure system requires verifying that the sealant actually holds under operating conditions, not just at rest. Mastic applied to a dirty or oily surface will fail in 90 days. More critically, many Dallas attics have asbestos-containing duct tape on pre-1990 systems; disturbing it without testing is a health hazard and a Texas Department of State Health Services violation. We test before we touch. Finally, the Rotobrush negative-air machine is not a Shop-Vac; it pulls 2,000+ CFM and requires proper HEPA filtration to avoid contaminating your living space. We’ve been called to jobs where a homeowner’s DIY “sealing” actually increased leakage by collapsing flex duct with excessive vacuum.
If you’re holding a Rotobrush part number and aren’t sure it matches your unit, call us at (469) 405-6133. We’ll cross-reference the serial number and tell you what fits before we schedule anything.
FAQs
Properly applied mastic with metal reinforcement lasts 15-20 years, but Dallas’s thermal cycling shortens that by roughly 20%. Attics here hit 140°F in July and drop to 40°F in January; that expansion and contraction stresses joints at the plenum and register boots first. We inspect these stress points specifically and use fiberglass-reinforced tape at transitions. Call (469) 405-6133 for a free estimate - we’ll show you exactly which joints are at risk.
Yes, if the flex duct itself is intact and the leak is at a joint, collar, or puncture under 2 inches. We patch with UL-181-rated foil tape and mastic, then pressure-test. If the flex is brittle, oil-soaked, or has multiple punctures, replacement is the only repair that lasts. We photograph the damage and explain which category you’re in before quoting. Call (469) 405-6133 for an exact assessment.
A single-run repair takes 2-3 hours; a partial system takes 4-6 hours; full Aeroseal injection takes a full day including pre-test and cure time. We don’t rush the cure: mastic needs 24 hours to reach full hardness, and we schedule return-air testing accordingly. The photo record is delivered by email within 24 hours of completion. Call (469) 405-6133 to schedule.
We carry sealant collars, mastic, reinforced tape, and flex duct in 4-inch, 6-inch, 8-inch, and 10-inch diameters on every truck, plus the adapters to interface with Rotobrush, Nikro, and Abatement Technologies negative-air machines. For Rotobrush-specific brush assemblies or drive components, we order OEM or verified aftermarket with 24-48 hour turnaround. Call (469) 405-6133 with your model number and we’ll confirm what’s in stock.
Tomas Reyes has a habit he picked up from years in the trade: show the duct first, talk about the solution second. The camera footage from your plenum doesn’t need embellishment. In Dallas properties near the Design District, where buildings from the 1960s still have original galvanized duct with failing joints, we’ve found that the debris pattern alone tells the story of what’s been breathing into the living space for decades. Tomas grew up in Queens, NY, learned the basics at Suffolk County Community College, and spent the better part of two decades learning what actually lives inside residential ductwork before bringing that standard to Dallas in 2013. He still writes every job note in plain language, and he still grows tomatoes in the backyard when he’s not running a camera through somebody’s return air.
Written by Tomas Reyes, Owner, CleanRun Air Duct Cleaning Dallas at CleanRun Air Duct Cleaning Dallas, serving Dallas and nearby areas.




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