Demilec Blown-In Insulation in West Hollywood: What to Know First
We provide independent Demilec blown-in insulation service in West Hollywood, typically completing attic jobs in one day with a written price delivered before any work starts. Most Demilec top-up or full-replacement jobs in a West Hollywood home this size run between $2,800 and $5,400 depending on existing conditions and air-sealing needs. Call (213) 306-2607 for a free estimate with a written scope, or text us if you prefer.
This page is for homeowners who have Demilec insulation products in their attic or walls and need to add, replace, or troubleshoot blown-in material. You might have Demilec cellulose from a 2015-2020 install that’s settled below label thickness, or you’re pairing Demilec with another system and need to know what’s compatible. Wes Okafor and our crew have worked on Demilec products across the LA basin since before the brand’s acquisition by Huntsman, and we know where the weak points hide.
How Demilec Products Fail - and How We Fix Them
- Demilec Sealection 500 open-cell spray foam adjacent to blown-in zones. In West Hollywood’s Santa Monica Boulevard corridor bungalows, we regularly find Sealection 500 overspray that bridged into attic floor joist bays meant for blown-in cellulose. The foam creates a hard dam that blocks proper fill depth. We cut back the overspray with a flush saw, air-seal the top plates properly, then blow new material to uniform depth.
- Demilec Heatlok HFO Pro closed-cell in kneewalls preventing dense-pack access. Heatlok HFO Pro was spec’d for many West Hollywood second-story additions around 2018-2021. When it shrinks away from studs in kneewall assemblies, the gap becomes a convection channel that undermines any adjacent blown-in wall insulation. We remove the compromised HFO, reseal with compatible foam, then dense-pack the stud cavity with cellulose to the proper density (3.5 pounds per cubic foot for walls).
- Demilec cellulose settling below labeled R-value in vented attics. Demilec’s blown cellulose is treated with borates for fire and pest resistance, but in West Hollywood’s warm-dry climate with significant diurnal temperature swings, we’ve measured 15-20% settlement in attics with inadequate air sealing underneath. The borate treatment is intact; the volume isn’t. We don’t just add more on top. We pull back to the deck, seal all top plates and penetrations, then reinstall to full labeled depth with a depth marker photo every 50 square feet.
- Demilec Agribalance organic-content degradation in rodent-affected attics. Agribalance’s higher organic content makes it attractive to nesting rodents, which we’ve found repeatedly in the Melrose District and Norma Triangle areas where mature trees bridge to rooflines. The fix isn’t more poison. We remove contaminated material, sanitize the deck, install steel mesh at all entry points, then replace with fresh Demilec cellulose or fiberglass depending on the homeowner’s preference and the specific rodent pressure.
- Incompatibility between early Demilec formulations and current blown-in top-ups. Pre-2016 Demilec cellulose used a different fiber treatment chemistry than current production. When homeowners add new blown-in material without checking, the interface can create a density gap that shows up on thermal imaging as a cold stripe. We core-sample through the attic floor, identify the original product year by fiber characteristics and borate concentration, then specify either matched Demilec current stock or a full removal and replacement with documented compatibility.
Our Demilec Blown-In Insulation Process

- 1
Call and scheduling. A live person answers, 24/7. We book a site visit, usually within 48 hours for West Hollywood addresses. You get a text when the technician is en route with a name and photo.
- 2
Attic inspection and blower-door baseline. We pressurize the house to 50 pascals (a blower-door test that shows, in one number, how much air your building envelope is losing) and document the CFM50 reading. We photograph existing Demilec product labels, depth markers, and any compromised areas.
- 3
Written price before any work starts. Under Haven Standard Clause 1, you receive a flat price, written scope, and written warranty before anyone lifts a tool. No exceptions. This includes our air-sealing scope, which is never optional.
- 4
Air sealing first, then insulation. Seal the leaks first. Then insulate. The R-value on the bag assumes you did it in that order. We seal top plates, can lights, plumbing and electrical penetrations, and chimney chases with appropriate fire-rated materials.
- 5
Blown-in installation to labeled depth with density verification. We blow Demilec cellulose or fiberglass to manufacturer spec, checking depth with a ruled probe every 50 square feet and photographing the results. For dense-pack wall work, we verify cavity pressure and install tell-tale tubes where accessible.
- 6
Post-job blower-door test and documented handoff. We run the blower door again, record the new CFM50, and deliver your before-and-after numbers plus a photo record of the completed work. The 365-Day Done Right Promise begins at signature.
Before
AfterWhat Demilec Blown-In Insulation Costs in West Hollywood
| Job Type | Typical Range | What Moves the Price |
|---|---|---|
| Attic top-up (existing adequate depth, partial) | $2,800 - $3,900 | Accessibility, square footage, whether air sealing is needed underneath |
| Full attic replacement with removal | $4,200 - $5,400 | Volume of material to remove, contamination (rodent/water), deck repairs |
| Dense-pack wall insulation (per wall) | $1,800 - $2,600 | Cavity depth, existing insulation state, interior or exterior access route |
| Air sealing scope (standalone or add-on) | $1,200 - $2,100 | Number of penetrations, can light count, chimney chase complexity |
These ranges reflect West Hollywood’s typical 1,200-2,400 square foot homes, many with modified rooflines from the 1980s-2000s additions. We also carry Reflectix and other brands if your project benefits from a hybrid approach. Call (213) 306-2607 for an exact written price - estimates are free, and we offer a Free Second Opinion on any written estimate you’ve already received.
Why West Hollywood Homeowners Call Topside Attic Insulation West Hollywood for Demilec Work

We’re an independent Demilec service provider - not affiliated with or authorized by Demilec - which means we work on what your home actually needs, not what a manufacturer program dictates. Our technicians are background-checked and uniformed; they know the difference between Sealection 500 and Heatlok HFO Pro by sight, and they know why it matters for your blown-in job.
Since 2016, we’ve sealed and insulated more than 9,000 homes. Every one started with a written price and ended with a documented record. On applicable jobs, you get before-and-after blower-door numbers you can reference when your utility bill arrives. The 365-Day Done Right Promise is backed by a written warranty, not a handshake. And when you call (213) 306-2607, a live person answers - no voicemail loops, no callback windows measured in business days.
FAQs
No. Demilec’s product warranties cover material defects, not who installs or services adjacent insulation. Our work is covered by our own 365-Day Done Right Promise and written warranty. If you have a specific Demilec material claim, we document the product batch and installation conditions so you have what you need for that separate process. Call (213) 306-2607 if you want us to review your paperwork with you.
Sometimes. We core-sample to identify the original product year and chemistry. Pre-2016 Demilec cellulose formulations differ from current production in fiber treatment, so a seamless top-up isn’t always possible. When matching isn’t advisable, we quote full removal and replacement with documented compatibility. We also carry Reflectix and other brands if a hybrid system makes more sense for your West Hollywood home.
Repair is cheaper only when the material is uncontaminated, adequately distributed, and the air sealing underneath is complete. In West Hollywood’s older housing stock, we find that two out of three “simple top-up” jobs need significant air sealing first, and about half have rodent contamination or moisture history that makes partial repair a false economy. We quote both paths when possible so you can compare real numbers. Call (213) 306-2607 for a free estimate.
Most attic jobs are one day. Dense-pack wall work or full removal-and-replacement jobs may run two days. We schedule within 48 hours for most West Hollywood addresses, and we don’t book more than we can finish properly. You’ll know the timeline in writing before anyone starts.
A written scope completion checklist, a photo record of the installed work, and on applicable jobs, your before-and-after blower-door test results in CFM50. This is standard on every job, not available on request. Wes keeps a worn copy of the California Energy Code on his truck seat for reference, and the crew finds that funny and practical.
Ready to get a written price before any work starts? Call (213) 306-2607 or text us for a free estimate on your Demilec blown-in insulation project in West Hollywood. We’ll read any competing quote with you - our Free Second Opinion is part of how we work.
Written by Wes Okafor, Owner, Topside Attic Insulation West Hollywood at Topside Attic Insulation West Hollywood, serving West Hollywood and nearby areas.