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 Boulder City
Duct sealing in Boulder City typically runs $400 – $950 for a whole-home system, with most jobs completed in a single day. We dispatch from our Las Vegas office and route crews to Boulder City homes inside our quoted arrival window, whether you’re in the Historic District off Nevada Way, up in Boulder City Heights, or out toward Lakeview along the bench. Call (361) 326-5060 for a free written estimate.
We’ve been working on Boulder City’s unique housing stock long enough to know the difference between a quick seal on modern flex duct and the real retrofit work this town demands. The 1931 Boulder Canyon Project Act froze new construction here for decades, so most of what we touch isn’t new at all. It’s 1930s – 1950s galvanized sheet-metal floor ducts, gravity furnace remnants, and mid-century ranch systems that were never designed to hold the static pressure your modern air handler generates. Our Duct Sealing team treats every Boulder City job as a custom assessment, because out here, the ductwork is almost always older than the cooling equipment connected to it.
Why Hollis Air Duct Cleaning Is Boulder City’s Preferred Duct Sealing Company
Hollis Air Duct Cleaning has been part of the Garrison Partners family since 2004. We operate under The Garrison Standard, which means written prices before any work starts, arrival inside the quoted window, and a 365-Day Done Right Promise backed in writing on every job. If the seal fails within a year, we come back and make it right at no charge, including a free second visit.
Our technicians are background-checked, uniformed, and equipped with professional-grade tools from Rotobrush, Nikro, and Abatement Technologies. We don’t send hardware-store tape and a prayer. We send mastic, mesh reinforcement, and negative-air containment systems sized for the job. Phones are answered by a live person 24 hours a day, seven days a week. No voicemail loops. No callback queues.
What separates us in Boulder City specifically is that we’ve seen enough of these legacy systems to know where they hide their leaks. Covered floor registers buried under decades of carpet. Evaporative cooler connections that were never properly integrated. Joints that were hand-folded in 1947 and haven’t been touched since. We document every job with before-and-after photos of your actual ducts, not stock images. You see what we sealed, and you see the static pressure improvement.
Duct Repair in Boulder City
Duct Repair in Boulder City usually means addressing the physical damage that decades of desert cycling have done to galvanized steel, or fixing the botched connections left by previous owners who tried to adapt gravity-furnace ductwork to forced-air systems. A typical repair here runs $250 – $600 depending on whether we’re patching a single branch run or rebuilding a plenum connection. Most calls come from the Historic District and Lakeview, where original floor ducts have corroded at the seams, been crushed by foundation settling, or had registers covered and forgotten.
When Repair Beats Replacement
Galvanized sheet metal from the 1940s and 50s is heavy-gauge stuff. If the metal itself is intact, we can often rebuild the joint, patch the hole, or rehang a sagging run for far less than a full replacement. We make that call with a camera inspection, not a guess. You’ll see the footage. We’ll explain what failed and why. Then we write the price down before we touch anything.
Common Botched Repairs We Fix
Foil tape over dirty joints. That’s the big one. Someone peeled back the carpet, slapped tape on dust-caked galvanized steel, and called it sealed. Six months later the tape’s curling and the system’s leaking 30% of its airflow into the crawl. We strip it back, clean the joint with agitation tools and negative air, then seal it with mastic and mesh. The Garrison Code says do it by the book, or don’t do it.
Air Duct Sealing in Boulder City
Air Duct Sealing in Boulder City is almost never the same job you’d get in a Henderson tract home. Here, we’re typically sealing legacy galvanized floor ducts that were originally sized for gravity furnaces, not modern air handlers. The static pressure requirements are completely different. A typical whole-home seal in Boulder City runs $400 – $950, with Historic District homes often landing at the higher end due to access challenges and the amount of pre-cleaning required. We seal with mastic and fiberglass mesh, not tape, because tape fails on the temperature swings these old metal ducts see.
The Pre-Seal Cleaning Step
Sealing over dust is building on sand. Boulder City’s desert dust is fine, gypsum-like stuff that embeds in every joint and seam. We run rotary brush agitation through the branch runs first, capture the debris with Nikro negative-air machines, then seal. Skip this step and your mastic is bonding to dust, not metal. We’ve had to redo other companies’ seal jobs because they skipped the prep. We don’t skip steps.
Static Pressure Testing After Sealing
We test before and after. Every job. The numbers go on your invoice. If the static pressure at the air handler doesn’t drop into manufacturer spec after we seal, we keep working until it does. That’s part of the 365-Day Done Right Promise. No hand-waving. No “it should be better now.” Numbers.
Trusted Brands We Service in Boulder City
We carry sealing and filtration products from Honeywell, Aprilaire, and Abatement Technologies, and our equipment roster includes Rotobrush rotary brush systems and Nikro negative-air machines. For Boulder City homeowners, this means we don’t wait on parts shipments from out of state. We stock mastic, mesh, register boots, and transition fittings sized for the oddball dimensions common in pre-1960 ductwork. A standard register boot from a big-box store won’t fit a 1952 round floor register without modification. We carry the adapters, or we fabricate them on site. Turnaround matters when your July electric bill is climbing and the system is leaking conditioned air into the dirt under your crawl.
Common Duct Sealing Problems We See in Boulder City Homes
- Sealing mastic applied over uncleaned galvanized joints. The dust and gypsum fines in Boulder City’s desert environment prevent proper adhesion. The seal looks fine in October. By February it’s cracking and peeling. We clean first, seal second, test third.
- Covered floor registers in Historic District homes. Registers buried under 1970s shag carpet or bedroom furniture aren’t delivering air to the living space, but they’re still pulling return air through the carpet fibers. The system leaks static pressure through the carpet itself. We locate, expose, and properly seal or cap these abandoned runs.
- Monsoon humidity wicking through evaporative-cooler-connected ductwork. July through September, humidity spikes loosen mastic on unsealed seams and can grow mold behind the seal. We seal cooler connections with moisture-rated products and verify with visual inspection.
- Gravity-furnace ductwork adapted to forced-air without resizing. The original 1930s – 1950s floor ducts are too large for modern air handlers, creating turbulent airflow and pressure drops at every unsealed joint. We seal what we can and flag where duct modification or replacement is the honest recommendation.
Pricing for Duct Sealing in Boulder City, NV
A typical whole-home duct sealing in Boulder City runs $400 – $950. Single-branch repairs or partial seals start around $250. Historic District homes with original floor ducts and covered registers usually run $750 – $950 because of the additional access work and pre-cleaning required. Mid-century ranches off Buchanan Boulevard with evaporative cooler connections typically fall in the $500 – $750 range.
What moves the price: how many branch runs need sealing, whether we need to expose covered registers, the condition of existing joints (clean metal seals better than corroded), and whether the system has a cooler connection requiring moisture-rated materials. We don’t do per-vent pricing. That’s a teaser game. We price per system, in writing, before we start. The number on the page is the number at the door.
Call (361) 326-5060 for a free estimate. We’ll inspect the system, show you the camera footage, and write the price down. No charge for the visit if you don’t move forward.
We Also Serve Cities Near Boulder City
Our crews route regularly to Henderson, Las Vegas, Nellis AFB, and North Las Vegas from the Las Vegas dispatch office. If you’re in Boulder City proper, you get the same crew, the same equipment, and the same written guarantee. We don’t subcontract outlying calls to random vans. Every Hollis job is a Hollis technician in a Hollis uniform with Hollis tools.
Serving Boulder City, NV - Our Local Coverage Area
We’re based in the Boulder City 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 Boulder City
Most 1940s galvanized floor ducts in Boulder City can be sealed if the metal is structurally sound. We camera-inspect first. If the metal is intact, we clean the joints with rotary brush agitation and negative air, then seal with mastic and mesh. Replacement only makes sense if the duct is crushed, severely corroded, or improperly sized for your current air handler. Call (361) 326-5060 and we’ll show you the footage before you decide.
Historic District homes require more access work. Covered registers must be located and exposed. Decades of dust and debris must be removed before sealing. The original hand-folded joints often need reinforcement, not just sealing. A 1990s Henderson tract home with exposed flex duct takes half the time. The extra labor and prep in Boulder City’s legacy homes account for the higher end of our $400 – $950 range. We write the specific price for your home before we start.
Ask for before-and-after static pressure readings. If the previous contractor didn’t test, you don’t know. We offer a verification inspection: camera the runs, pressure-test the system, and document any leaks the remodel crew missed. Common misses on Buchanan Boulevard ranches include cooler connections left unsealed and original floor registers capped with tape instead of proper plugs. The inspection runs $150, credited toward any sealing work we do.
Yes. The fine gypsum-like dust prevents mastic adhesion if joints aren’t cleaned first. July – September humidity spikes wick through unsealed evaporative cooler connections and can re-wet seams, loosening mastic and promoting mold growth behind the seal. We use moisture-rated products on cooler connections and always clean before sealing. The 365-Day Done Right Promise covers seal failure from either cause – we come back and make it right at no charge.
We can, but it requires specific materials and technique. Cooler-connected ducts see seasonal wet-dry cycles that standard mastic isn’t rated for. We seal these connections with moisture-rated mastic and reinforced mesh, then verify with visual inspection after the first monsoon season. If you’re running a cooler in summer and a furnace in winter, the duct sees more stress than a standard forced-air system. We factor that into our material choice and our guarantee. Call (361) 326-5060 to schedule an assessment.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Boulder City and the greater Las Vegas valley since 2004.




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