Demilec Crawl Space Encapsulation & Vapor Barrier in West Hollywood: What to Know First
We provide independent Demilec crawl space encapsulation and vapor barrier service in West Hollywood, typically completing diagnostic-to-cleanup jobs in one to two days. Most Demilec crawl space systems we encounter in this market run between $2,800 and $5,400 depending on whether we’re addressing a failing open-cell application, a compromised vapor barrier, or full encapsulation with conditioned-air integration. This page is for homeowners who’ve found Demilec spray foam, rigid board, or vapor barrier products in their crawl space and need to know whether the existing work can be salvaged or needs complete replacement. Call us at (213) 306-2607 for a free written estimate - we read what you have before we quote, and the price you get is the price you pay.
How Demilec Products Fail - and How We Fix Them
- Demilec SEALECTION 500 open-cell crawl space applications absorbing ground moisture. SEALECTION 500 is a water-blown open-cell foam - meaning the cells are intentionally interconnected - and in West Hollywood’s clay-heavy soils around the Norma Triangle and Spaulding Square, capillary rise can wick moisture into the foam substrate. We’ve pulled SEALECTION that weighed three times its installed mass. Our fix: remove the saturated foam back to dry substrate, install a proper 6-mil or thicker polyethylene ground vapor barrier first, then re-apply only if the crawl space is fully encapsulated with dehumidification.
- Demilec Heatlok XT rigid board delaminating from crawl space stem walls. Heatlok XT is a closed-cell spray foam that can be applied as rigid board or in-place, but when board stock is adhesive-mounted to below-grade concrete in older West Hollywood bungalows, seasonal soil expansion against shallow footings cracks the bond line. We see this most on homes north of Santa Monica Boulevard with original 1920s-40s foundations. Our fix: mechanical fastening with masonry-capable fasteners, not adhesive alone, plus a termination seal to the wall using compatible Demilec flashing or, where the board is too compromised, full replacement with mechanically secured new stock.
- Demilec 500 Demilec vapor barrier polyethylene failing at seams and penetrations. The factory-laminated 6-mil and 10-mil rolls Demilec distributed through the mid-2010s carried a 10-year warranty, but the pressure-sensitive seam tape - especially on the 6-mil product - degrades in crawl spaces with seasonal RH swings above 70 percent. West Hollywood’s winter marine layer pushes many crawl spaces into that range December through March. Our fix: full seam re-tape with butyl-based tape rated for below-grade use, or complete barrier replacement with cross-laminated scrim-reinforced product that won’t tear on re-entry.
- Demilec closed-cell applications applied over unsealed rim joists creating double trouble. We find this in flipped properties where a prior contractor sprayed Demilec closed-cell directly over dirty, unsealed framing - the foam bonds to dust and rodent debris, not wood, and the rim joist leaks continue behind a now-concealed surface. Our fix: surgical removal of the compromised foam section, mechanical cleaning of the substrate, air-sealing the rim joist with compatible sealant, then re-application with proper substrate preparation documented in the photo record.
- Demilec HFO-blown formulations (Heatlok HFO High Lift) shrinking in constrained crawl spaces. The HFO blowing agent in newer Heatlok formulations can exhibit slight dimensional change during full cure, which becomes a problem in West Hollywood’s tight 24-inch-clearance crawl spaces where the foam is constrained between joists and can’t expand freely. We see 3-5 percent linear shrinkage creating gaps at the stud edge. Our fix: specify lower-lift passes in constrained spaces, or switch to a two-component pour-in-place application where access permits, with each pass thickness controlled to manufacturer spec.
Our Demilec Crawl Space Encapsulation & Vapor Barrier Process
- 1
Call and scope. A live person answers - no voicemail - and we schedule a diagnostic visit, usually within 48 hours in West Hollywood. You receive a text with your technician’s name when they’re en route.
- 2
On-site diagnostic with photo documentation. We enter the crawl space with full PPE, identify the Demilec product line and installation date where visible, and photograph every compromised area. We test for moisture content in wood substrates and ambient relative humidity.
- 3
Written price before any work starts. Under Haven Standard Clause 1, you get a flat price, written scope, and written warranty before anyone lifts a tool. No exceptions. We also offer a Free Second Opinion on any competing written estimate.
- 4
Parts decision: OEM Demilec vs. quality aftermarket. For vapor barrier replacement, we source cross-laminated polyethylene from multiple suppliers - no proprietary lock-in. For foam removal and re-application, we use Demilec-compatible chemistry or, where the homeowner prefers, equivalent-performance products from Icynene or Johns Manville. We explain the trade-offs in writing.
- 5
Execution with air-sealing priority. Seal the leaks first. Then insulate. The R-value on the bag assumes you did it in that order. We air-seal rim joists, sill plates, and penetrations before any new insulation or barrier goes in. On applicable jobs, we run a blower-door test - pressurizing the house to 50 pascals - to quantify the envelope improvement.
- 6
Cleanup, documentation, and guarantee. Every job closes with a Documented Photo Record: before, during, after. On air-sealing jobs, before-and-after blower-door numbers are included. The 365-Day Done Right Promise applies to all work. If it’s not done right, we make it right.
Before
AfterWhat Demilec Crawl Space Encapsulation & Vapor Barrier Costs in West Hollywood
Most Demilec crawl space jobs we handle in West Hollywood fall into these ranges:
- Vapor barrier repair/replacement only (Demilec 6-mil or 10-mil polyethylene): $1,800-$3,200 for 800-1,200 square feet of crawl space, including seam re-tape with butyl-based product or full barrier replacement with scrim-reinforced material.
- Partial encapsulation (barrier + rim joist air sealing, no foam): $2,800-$4,200. Price moves with accessibility - 18-inch clearance adds labor hours versus 36-inch clearance.
- Full encapsulation with conditioned-air integration (barrier, air sealing, dehumidification, new Demilec or equivalent closed-cell foam): $4,200-$5,400. Homes south of Melrose with active sump pumps or drainage issues may need pre-encapsulation drainage work, which we quote separately.
- Saturated foam removal and replacement: Add $800-$1,400 to any encapsulation scope for surgical removal of compromised SEALECTION 500 or Heatlok XT, substrate drying, and re-application.
What moves the price: crawl space clearance height, active moisture sources requiring drainage remediation, extent of existing Demilec product failure, and whether the home has a post-2020 Title 24 energy compliance requirement that affects material specification. Call (213) 306-2607 for a free written estimate - we read your crawl space before we name a number.
Why West Hollywood Homeowners Call Topside Attic Insulation West Hollywood for Demilec Work
We’ve been inside crawl spaces from the Sunset Strip to West Hollywood West since 2016, and we’ve learned that Demilec products fail in predictable ways when the prep work is skipped. Our technicians are background-checked, uniformed, and trained to identify Demilec-specific installation errors - not generic “bad foam” diagnoses. We also service Reflectix radiant barrier systems, which matters in West Hollywood’s mixed housing stock where a prior owner may have layered multiple products. Every job gets the Haven Standard treatment: written price first, documented photo record at close, and the 365-Day Done Right Promise backing the labor. We’re independently owned and operated - not a franchise - and Wes Okafor reviews every Demilec remediation scope personally before it goes to the crew.
FAQs
Demilec’s product warranties cover material defects, not installation labor, and they do not require manufacturer-authorized service for the material warranty to remain valid. Our work is covered by our own 365-Day Done Right Promise and written warranty. If you have a valid Demilec material claim, we document the failure and help you file it - but we do not represent Demilec. Call (213) 306-2607 and we’ll review what coverage you have.
We typically schedule diagnostics within 48 hours for active moisture intrusion or compromised vapor barriers, and we carry common Demilec-compatible materials on our trucks for same-day stabilization when the scope permits. True emergencies - structural saturation threatening floor joists - get priority scheduling. Call (213) 306-2607 for availability.
Repair is cheaper when less than 30 percent of the vapor barrier is compromised and the foam substrate is dry and well-bonded. Full replacement becomes cost-effective when we find multiple failure modes - saturated open-cell foam, delaminated rigid board, and failed seam tape - because addressing each separately exceeds the cost of clean removal and proper re-installation. We quote both paths when both are viable. Call for a free written estimate.
We can match the thermal performance and air-sealing characteristics of existing Demilec closed-cell or open-cell foam, but exact visual match is not guaranteed - aged foam yellows and oxidizes, and new product will appear different. We specify the replacement chemistry in writing and ensure the new-to-old transition is properly sealed. For homeowners pursuing Title 24 compliance, we verify the replacement meets current code requirements, which may differ from the original installation spec.
You receive a written scope completion checklist, a Documented Photo Record of all work areas, and on air-sealing jobs, before-and-after blower-door readings showing the measured improvement. The 365-Day Done Right Promise and our written warranty are included in the packet. This is Haven Standard - have it in writing - and it’s how we’ve closed every one of our 9,000-plus jobs since 2016.
Written by Wes Okafor, Owner, Topside Attic Insulation West Hollywood at Topside Attic Insulation West Hollywood, serving West Hollywood and nearby areas.