Trusted Attic Air Sealing for Leander Homeowners
Attic air sealing in Leander typically costs $1,200-$2,800 for a complete job, and most homes we seal show a 30-50% reduction in air leakage on the blower-door test. See our guide to how much Attic Air Sealing costs for a detailed breakdown. We’re usually on-site within 24-48 hours for standard scheduling, with same-day service available when the schedule allows. Call (737) 252-7159 for a written price before any work starts.
We’ve sealed and insulated more than 9,000 homes since 2016, and we’ve learned that Leander’s combination of hot summers, occasional hard freezes, and the Hill Country’s shifting clay soils creates a specific problem: attics here leak conditioned air through gaps that open and close as the house settles. We also offer Cedar Park Attic Air Sealing for homes facing the same challenges just north of Leander. That means your HVAC runs longer in July, your upstairs rooms stay hot in August, and your energy bills climb even after you’ve added insulation. The fix isn’t more insulation over the leaks. It’s sealing the leaks first, then insulating. That’s the sequence we follow on every job, documented with before-and-after blower-door numbers so you can see the difference in CFM50 - the single figure that tells you how much air your building envelope was losing before we started and how much it loses after we’re done.
Wes Okafor has led this operation since day one, and our crews are background-checked, uniformed, and trained to the Haven Standard: written price, written scope, written warranty before anyone lifts a tool. Calls are answered by a live person 24/7. No voicemail loops. No callback windows measured in business days.
What Our Attic Air Sealing Service Includes
Attic Floor Air Sealing
The attic floor is the primary boundary between your conditioned living space and the unconditioned attic. In Leander homes built between 2015 and 2025, we regularly find gaps along the drywall-to-top-plate joint, plumbing and electrical penetrations, and the seams around chimney chases that together leak as much air as an open window. We seal these with attic air sealing in Leander using fire-rated caulk, expanding foam rated for the specific penetration type, and rigid blocking where code requires it. Every gap gets addressed before any insulation goes in. We’ve seen blower-door readings drop by 800-1,500 CFM50 from this step alone on a typical 2,400-square-foot home in the Crystal Falls or Travisso areas.
Top Plate & Penetration Sealing
Top plates are the horizontal framing members where wall studs meet the ceiling drywall, and they’re rarely sealed by builders in the Leander market. Each stud bay creates a small chimney effect, pulling conditioned air upward in winter and drawing superheated attic air downward in summer. We seal every accessible top plate joint with acoustical sealant or low-expansion foam, depending on the gap width and surrounding materials. Penetrations - where wiring, plumbing vents, and HVAC lines pass through - get gaskets or fire-stop foam as appropriate. In neighborhoods like Mason Hills and Bryson, where production builders prioritized speed over envelope tightness, this step often reveals the single largest source of hidden air leakage in the home.
Can Light & Duct Boot Sealing
Recessed can lights are essentially holes in your ceiling, and in Leander’s climate they do double damage: leaking conditioned air year-round and creating thermal bypasses that melt snow on your roof in rare freeze events, leading to ice dam risk. We seal IC-rated cans from above with pre-formed covers or site-built boxes sealed with fire-rated materials, and we replace non-IC cans with sealed, insulated housings where the homeowner approves. Duct boots - the sheet-metal transitions between your ductwork and ceiling registers - often separate from drywall as the house settles on Hill Country clay. We reseat and seal every boot with mastic or foil tape rated for the temperature range, then verify with a smoke pencil or theatrical fog to confirm no bypass. This is standard on every job, not an upsell.
Attic Hatch Sealing
The attic hatch is the most obvious leak in most Leander homes and the most often ignored. A 1/4-inch gap around a standard pull-down stair unit leaks as much air as a 6-inch square hole in your wall. We build site-fitted dams from rigid foam board around hatch openings, seal the dam to the attic floor with low-expansion foam, and install weatherstripping on the hatch itself rated for the temperature swing it will see. For pull-down stairs, we install insulated covers with positive latches that maintain the thermal and air barrier when closed. In Leander’s summer attic temperatures that regularly exceed 140°F, an unsealed hatch is a direct pathway for that heat to radiate into your hallway and force your air handler to run overtime.
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 for Attic Air Sealing
We’ve worked with Owens Corning air-sealing accessories and insulation systems on hundreds of Leander-area jobs, particularly in new construction where the builder spec’d their AttiCat blown-in system but skipped the sealing step. We stock Owens Corning FOAMULAR rigid board for hatch dams and their ProPink sealants for compatible applications, and we know where their system interfaces require supplemental detailing that the original installer missed. For homeowners with Demilec open-cell or closed-cell spray foam in adjacent assemblies, we coordinate our air-sealing strategy to maintain the foam’s vapor profile and avoid creating unintended condensation planes in the mixed-humidity Leander climate.
We also source GreenFiber cellulose for homeowners who want a plant-based insulation topcoat after sealing, and we’ve installed Icynene water-blown open-cell systems in custom homes around Lago Vista and Lakeway where the architect specified a continuous air barrier. Whether your home has Owens Corning, Demilec, GreenFiber, Icynene, or any other make, we can help. Our material familiarity matters because the sealing strategy changes based on what the insulation layer will be - vapor-open, vapor-closed, dense-pack, or loose-fill - and we specify accordingly.
Before
AfterSigns You Need Attic Air Sealing Right Now
- Upstairs rooms stay 5-10°F hotter than downstairs in summer. This isn’t normal in a properly sealed home. In Leander, where afternoon attic temperatures can reach 140-150°F, unsealed top plates and penetrations create a thermal siphon that dumps heat into second-floor bedrooms. Your thermostat is downstairs, so it doesn’t know to call for more cooling. The result is a hot upstairs and an overworked system.
- Your energy bill spikes every July and August despite normal usage. We’ve reviewed utility bills with homeowners in Cedar Park and Leander who saw summer cooling costs drop 20-35% after sealing alone, before any insulation was added. The HVAC isn’t fighting leakage, so it cycles normally instead of running continuously.
- You feel drafts from ceiling fixtures, outlets, or baseboards on exterior walls. These are telltale signs that attic air is being pulled down through the wall cavity due to the stack effect - warm air leaking out the top of the house, replaced by outside air entering at the bottom. In Leander’s older neighborhoods like Old Town Leander, balloon framing makes this worse by providing an uninterrupted path from basement or crawl space to attic.
- Insulation looks settled, stained, or has dark streaks near the edges. Dark streaks on fiberglass batts are dust filtering through air leaks, not mold. The insulation is acting as an air filter because the leak is moving through it. Adding more insulation over this just buries the problem and reduces the new material’s effectiveness by 30-50%.
- Your HVAC system was sized correctly but can’t maintain setpoint on design days. Manual J load calculations assume a certain envelope tightness. If your Leander home leaks at 4,000+ CFM50 when it was designed for 2,500, the system is undersized for the actual load. Sealing brings the load back in line with the equipment capacity, often eliminating the perceived need for a larger unit.
Our Attic Air Sealing Process - Step by Step
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Schedule and arrival. You call (737) 252-7159 and speak to a live person. We book a time that works for you, and you get a text when your technician is en route with a name and photo. Under Haven Standard: Arrive on schedule, you get a named technician. We don’t do four-hour windows.
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Visual inspection and blower-door baseline. We walk the attic with you if you’d like, or document with photos if you prefer. Then we run a blower-door test - a pressurization reading that shows, in one number, how much air your building envelope is losing. This is your baseline CFM50, and it’s the number we’ll beat. We also use an infrared camera to map thermal bypasses that aren’t visible to the eye, particularly around complex roof geometries common in Leander’s custom homes.
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Written price and scope before any work starts. Haven Standard Clause 1: flat price, written scope, written warranty before anyone lifts a tool. You’ll know exactly what we’re sealing, what materials we’re using, what the blower-door target is, and what you pay. No surprises, no “while we were up there” add-ons. If you have a competing quote, bring it - we offer a Free Second Opinion on any written estimate and will read it with you line by line.
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Air sealing execution. We seal in this order: attic hatch, then top plates and penetrations, then can lights and duct boots, then attic floor joints and large bypasses. Each category gets the appropriate material - fire-rated caulk, low-expansion foam, rigid blocking, mastic, or pre-formed covers - and we photograph every critical detail for your Documented Photo Record. In Leander’s climate, we pay particular attention to humidity-sensitive assemblies; we don’t create condensation risks by sealing the wrong side of a vapor profile.
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Blower-door verification and documentation. We run the blower door again. You get the before number, the after number, and the percentage improvement. Most Leander homes we seal show 30-50% reduction in CFM50; some exceed 60% when the builder left significant gaps. You also get your written warranty, your 365-Day Done Right Promise documentation, and a link to your photo record. If it’s not done right, we make it right - that’s in writing too.
How Much Does Attic Air Sealing Cost in Leander?
Most complete attic air sealing jobs in Leander run $1,200-$2,800 for homes between 1,800 and 3,500 square feet. Here’s how that breaks down by scope:
| Scope | Typical Range | What Drives It |
|---|---|---|
| Attic floor sealing only (no hatch, no cans) | $800-$1,400 | Accessibility, number of penetrations, existing insulation depth |
| Complete seal: floor, top plates, penetrations, hatch | $1,400-$2,200 | Home size, attic height, number of plumbing/HVAC penetrations |
| Complete seal + can light covers + duct boot reseal | $2,000-$2,800 | Number of cans, duct configuration, need for IC-rated replacements |
| Large custom home (4,000+ sq ft, complex roof) | $2,800-$4,500 | Multiple attic zones, scissor trusses, conditioned attic strategies |
What moves the price: attic accessibility (a 12/12 pitch with limited headroom takes longer than a walk-up), the number and type of penetrations (a kitchen with six can lights and a vent hood duct is more complex than a bedroom with one light), and whether we need to remove existing insulation to access the leaks. We never quote over the phone without seeing the attic; every price is site-specific and written before work starts.
How to avoid overpaying: get a written scope that specifies what’s being sealed and with what materials. A quote that says “air seal attic” without itemizing the components is a red flag. Ask for the blower-door target; if the contractor doesn’t measure before and after, you’re buying a promise, not a result. At Topside Attic Insulation Leander, the estimate is free, the price is flat, and the documentation is included. Call (737) 252-7159 for your written estimate - we’ll read any competing quote with you as part of our Free Second Opinion.
Attic Air Sealing Near Leander - Our Service Area
We run sealed and insulated jobs across the northern Austin metro corridor, with typical drive times of 15-30 minutes to attic air sealing in Cedar Park and attic air sealing in Brushy Creek. We also regularly service Jollyville, Lago Vista, Georgetown, Round Rock, Wells Branch, Lakeway, Pflugerville, Hutto, and Lost Creek. Response time in Leander proper is same-day or next-day for most requests; outlying areas typically see 24-48 hour scheduling. If you’re unsure whether you’re in our range, call (737) 252-7159 - a live person will confirm availability and book you directly.
Serving Leander, TX - Our Local Coverage Area
We’re based in the Leander area and know this community well, and we also provide Attic Air Sealing in Georgetown for homeowners north of our home base. Use the map below to see our full service coverage - if you’re nearby, we can almost certainly help.
Frequently Asked Questions - Attic Air Sealing in Leander
Attic air sealing is the process of closing gaps, cracks, and penetrations in the ceiling plane and attic floor that allow conditioned air to escape into the unconditioned attic space. At Topside Attic Insulation Leander, we use a blower-door test to measure your home’s leakage in CFM50, then systematically seal top plates, penetrations, can lights, duct boots, and the attic hatch with fire-rated caulk, low-expansion foam, and rigid blocking as appropriate. The result is a documented reduction in air leakage - typically 30-50% - before any insulation is added.
Most residential attic air sealing jobs in Leander take one full day for homes up to 3,000 square feet, and one to two days for larger or more complex roofs. We arrive with a written scope and complete the work without returning for materials. You’ll have your blower-door results, photo documentation, and warranty paperwork before we leave. Call (737) 252-7159 to check current scheduling - we’re typically booking 24-48 hours out.
A typical complete attic air sealing job in Leander costs $1,200-$2,800 depending on home size, attic accessibility, and the number of penetrations to seal. Attic floor sealing alone runs $800-$1,400, while jobs with can light covers and duct boot reseal reach the upper end of the range. Every estimate is free, written, and itemized before any work starts - no verbal quotes, no surprises. Call (737) 252-7159 for your specific price.
Yes. We’ve worked with Owens Corning air-sealing accessories and insulation systems on hundreds of jobs, and we’ve installed and sealed around Icynene water-blown open-cell foam in custom homes throughout the Hill Country. We also coordinate with Demilec and GreenFiber systems where the homeowner has existing material. Whatever brand is in your attic, we know how to seal against it without compromising the assembly. Bring us your concerns - estimates are free.
We don’t treat air sealing as an emergency service because the risks are cumulative, not immediate. However, we do answer calls 24/7 and can often schedule next-day service if you’re experiencing severe comfort issues or preparing for a real estate transaction with a deadline. If you’ve had insulation displaced by rodents or water damage, we also offer attic cleaning and rodent proofing as a related service. Call (737) 252-7159 anytime - a live person will pick up.
Every attic air sealing job carries our 365-Day Done Right Promise: if it’s not done right, we make it right. You also receive a written warranty specific to the materials and scope before work begins. The Haven Standard requires this in writing - no exceptions. If your blower-door result doesn’t meet the target we set in your written scope, we return and correct at no charge. That promise is backed by more than 9,000 completed jobs since 2016.
Clear a path to the attic hatch and remove any stored items within 3 feet of the opening. We need access to all ceiling penetrations, so if you have delicate items under can lights or near ceiling registers, move them. We bring our own lighting, protection for your floors, and containment for the work area. You don’t need to be home for the entire job, but we do a walkthrough with you at completion to review the blower-door results and photo documentation. Call (737) 252-7159 to book - we’ll confirm any site-specific prep when we schedule.
Schedule Your Attic Air Sealing Service in Leander Today
Call (737) 252-7159 now and speak to a live person, 24/7. We’ll schedule your free estimate, provide a written price before any work starts, and document every detail of the job from blower-door baseline to final verification. Wes Okafor and the team at Topside Attic Insulation Leander have sealed and insulated more than 9,000 homes under the Haven Standard since 2016. Your attic shouldn’t leak. Let’s prove it with numbers.
Written by Wes Okafor, Owner at Topside Attic Insulation Leander, serving Leander, Attic Air Sealing in Leander, Cedar Park, Brushy Creek, and the northern Austin metro since 2016.