Demilec Wall Insulation in Los Angeles: What to Know First
We provide independent Demilec wall insulation service in Los Angeles, typically scheduling within 48 hours and completing most residential jobs in a single day. Our written price - flat, itemized, delivered before any work starts - runs between $2,800 and $6,400 for standard Demilec injection foam or drill-and-fill wall jobs depending on wall area, cavity condition, and whether existing material needs extraction first. This page is for homeowners who already have Demilec product in their walls and need to know whether it’s failing, what fixing it actually involves, and what documentation they’ll walk away with. Call (628) 226-1097 to schedule a free estimate or bring us a competing written quote for our free second opinion.
How Demilec Products Fail - and How We Fix Them
- Demilec 500 open-cell shrinkage in vented wall cavities. The 500 series - a half-pound open-cell foam - can pull away from framing members in Los Angeles’s combination of dry Santa Ana periods and seasonal marine layer moisture, especially in pre-1980s stucco homes with no interior vapor retarder. We find this most often in Silver Lake and Echo Park bungalows where the original lath-and-plaster was retrofit with Demilec in the 2010s. Our fix: extract the compromised foam with mechanical removal and HEPA-contained vacuum, seal the cavity with closed-cell injection at 2.0 lbs density, then verify with thermal imaging.
- Demilec 2000 closed-cell off-ratio curing in hot-wall conditions. The 2.0 lb closed-cell 2000 series demands precise A-side/B-side temperature control; when installed on west-facing walls in August without drum conditioning, we’ve measured core densities below 1.8 lb/ft³ with accompanying R-value loss. We re-insulate these walls by removing the failed material and re-applying with heated hose sets and real-time density checks - not guesswork.
- Demilec Heatlok HFO shrinkage at top plates and rim joists. Heatlok HFO, Demilec’s newer low-GWP formulation, uses a hydrofluoroolefin blowing agent that can exhibit post-installation shrinkage of 3-5% in the first 90 days if the substrate temperature drops below 60°F during cure. Los Angeles garages and unconditioned knee walls in the Hollywood Hills see this every January. We cut back the shrunken material, prime the substrate, and re-apply in conditioned staging - or switch to a non-HFO alternative if the thermal boundary location makes temperature control impossible.
- Demilec SEALECTION 500 moisture trapping behind vinyl siding. SEALECTION 500 - Demilec’s mid-density open-cell product - is vapor-permeable but not vapor-open enough for walls wrapped in non-breathing vinyl over building paper, a common combination in 1960s-1980s San Fernando Valley tract homes. Moisture accumulates at the sheathing interface, we see OSB swelling at the nail lines. We remove the SEALECTION, install a proper drainable housewrap or switch to a vented rainscreen detail, then re-insulate with a material matched to the new assembly drying potential.
- Demilec Agribalance cellulose-blend settling in balloon-framed walls. Agribalance, Demilec’s soy-based open-cell formulation, was marketed heavily in green-building circles around 2012-2016 and installed in some Los Angeles ADU and addition projects. In balloon-framed walls without fire blocking - still legal in many pre-1960 Los Angeles neighborhoods - the material settles toward the sill plate, leaving a 12-18 inch uninsulated collar at the top of each stud bay. We dense-pack these cavities with stabilized cellulose or inject closed-cell foam depending on the fire-blocking retrofit required by current LADBS code.
Our Demilec Wall Insulation Process
- 1
Call and scope. A live person answers; we schedule a site visit, usually within 48 hours. You receive a text with the technician’s name when they’re en route.
- 2
Blower-door test and thermal scan. We pressurize the house to 50 Pascals - a standard pressure differential that reveals air leakage paths - and record CFM50 baseline. Then we run a FLIR camera to map cavity voids, shrinkage gaps, and moisture anomalies in the Demilec.
- 3
Written price before any work starts. Flat price, itemized scope, written warranty. Haven Standard Clause 1. No work begins until you have it in writing.
- 4
Cavity preparation and material selection. We extract failed Demilec mechanically, never by pressure-washing (that traps moisture in the stud bay). For re-insulation, we select OEM Demilec refill stock or specify an equivalent from Icynene, Johns Manville, or Reflectix depending on assembly requirements and your preference - no proprietary lock-in.
- 5
Installation with real-time verification. For spray applications, we pull core samples and weigh for density. For injection foam, we monitor fill pressure to avoid overpacking that bows drywall or stucco.
- 6
Post-test, photo record, and sign-off. We re-run the blower door and hand you a written summary: before and after CFM50, installed R-value, product data sheets, and a Documented Photo Record of the work. The 365-Day Done Right Promise attaches automatically.
Before
AfterWhat Demilec Wall Insulation Costs in Los Angeles
| Job Type | Typical Range | What Moves the Price |
|---|---|---|
| Demilec injection foam, standard 2×4 wall (per sq ft of wall area) | $4.50-$7.20 | Cavity access method (interior drywall cut vs. exterior drill-and-fill), floor level, scaffolding needs |
| Demilec extraction and re-insulation, single-family home | $2,800-$4,600 | Extent of failed material, hazardous material handling (pre-2012 formulations), disposal weight |
| Demilec 2000 closed-cell, high-R retrofit (per sq ft) | $6.80-$10.50 | Substrate temperature control requirements, multiple lifts for thickness, hot-wall orientation |
| Interior wall soundproofing with Demilec open-cell | $3,200-$5,800 | STC rating target, need for resilient channel decoupling, electrical box sealing detail |
| Exterior wall insulation with drainage plane remediation | $5,400-$8,900 | Housewrap replacement, rainscreen addition, LADBS permit and inspection scheduling |
Most Los Angeles homes in our records fall between $3,400 and $5,200 for a complete Demilec wall insulation job with extraction. Call (628) 226-1097 for an exact written price - estimates are free, and we read competing quotes with you at no charge.
Why Los Angeles Homeowners Call Topside Attic Insulation Los Angeles for Demilec Work
We’ve sealed and insulated over 9,000 homes since 2016, and a growing share of our Los Angeles wall work involves extracting and replacing Demilec installed by others - often green-builders who led with product marketing instead of assembly science. Wes Okafor and our crew run a blower-door test on every applicable job, publish the before-and-after numbers, and hand you the documentation before we leave. We’re not a Demilec dealer; we’re an independent service provider who sources Demilec when it fits, Icynene when it doesn’t, Reflectix for radiant barrier complement, and Rockwool for fire-rated assemblies. The 365-Day Done Right Promise applies to all of it. Calls are answered by a live person, 24/7.
FAQs
No - Demilec’s product warranty covers material defect, not installation, and is unaffected by who performs subsequent service. We document the existing product lot number when visible and photograph cavity conditions before touching anything, so any future material claim has a clear baseline. Call (628) 226-1097 if you want us to review your original installation paperwork with you.
Most residential Demilec wall jobs we complete in Los Angeles finish in one working day; extraction-and-replace projects run two days, with the second day typically shorter. We schedule LADBS inspections when required - usually for exterior wall work or fire-blocking modifications - and coordinate around your availability, not ours. Call for a written timeline with your estimate.
Spot repair is cheaper only when the failure is isolated to one or two stud bays and the remaining material passes density and adhesion testing. In our Los Angeles experience, Demilec shrinkage and off-ratio curing propagate beyond the visible defect; we find that 70% of jobs that start as “repair” become partial or full extraction once we probe adjacent cavities. We quote both paths in writing so you can compare actual numbers, not assumptions.
We can source current-production Demilec formulations - 500, 2000, Heatlok HFO - through our distributor network. Discontinued lines like early Agribalance lots or pre-2018 SEALECTION formulations cannot be matched exactly; in those cases we specify the closest modern equivalent and document the substitution in your written scope. We never represent aftermarket product as OEM.
The clearest sign is a blower-door number that hasn’t improved since installation, or has degraded - we see this in Los Angeles homes where the original installer skipped pre-test documentation. Other indicators: cold wall surfaces in January despite heating, musty odor at baseboards, or visible shrinkage gaps at electrical boxes. We run the diagnostic test for free during your estimate and show you the thermal imagery in real time. Call (628) 226-1097 to schedule.
Seal the holes first. Then measure the R-value. In that order.
Ready to fix your Demilec wall insulation the right way? Call (628) 226-1097 to speak with a live person now, or text us to schedule your free estimate and written price. We serve Los Angeles and nearby areas including Pasadena, Glendale, Culver City, and the San Fernando Valley.
Written by Wes Okafor, Owner & Lead Insulation Technician, Topside Attic Insulation Los Angeles at Topside Attic Insulation Los Angeles, serving Los Angeles and nearby areas.