Johns Manville Crawl Space Encapsulation & Vapor Barrier Nationwide | Walt’s Insulation

Johns Manville Crawl Space Encapsulation & Vapor Barrier in Santa Monica: What to Know First

Johns Manville crawl space encapsulation and vapor barrier work in Santa Monica typically runs $2,800 to $9,500 depending on square footage, access, and how much moisture damage already exists. We handle the full scope: vapor barrier installation, encapsulation, insulation, moisture control, and cleanout. Most jobs are done in one to two days, and every one of them is backed by our lifetime Done Right Promise. If you own a Johns Manville product and your crawl space is damp, musty, or showing signs of moisture problems, call us at (424) 396-5828 and a live person answers. This page is for Santa Monica homeowners who want straight answers about their Johns Manville crawl space, not a sales pitch.

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How Johns Manville Products Fail - and How We Fix Them

Johns Manville makes solid insulation and vapor barrier products, but nothing lasts forever in a Santa Monica crawl space. The marine air off the Pacific pushes moisture into every gap, and we see the same failure patterns year after year. Here’s what actually happens, model by model:

• Johns Manville ComfortTherm Batts in crawl space ceilings: The kraft facing traps moisture against the subfloor when Santa Monica’s coastal humidity sits above 70% for weeks at a time. We find soggy batts sagging onto pipes and ductwork. The fix is removal, proper air sealing, and reinstalling with the facing oriented correctly against the conditioned side. We pull and replace these regularly.
• Johns Manville AP Foil-Faced Polyiso in rim joist bays: The foil facing can delaminate over time when exposed to repeated condensation cycles. Once the facing separates, the insulation loses its air-barrier function and the rim joist starts sweating. We cut out the delaminated sections, treat the framing, and install new polyiso with sealed edges.
• Johns Manville Spider (spray-in fiberglass) in crawl space walls: Spider is a good product, but if it was installed without proper netting tension, it slumps. In a high-moisture crawl space, slumped Spider leaves bare wall sections that conduct cold and collect condensation. We re-densify or remove and replace with a system that holds its shape in damp conditions.
• Johns Manville vapor barrier liners (6-mil and 10-mil): The thin stuff tears. We’ve seen 6-mil poly shredded by rats, punctured by rocks, and pulled apart at the seams. A torn vapor barrier in a Santa Monica crawl space means ground moisture goes straight into your floor framing. We remove and replace with reinforced 10-mil or thicker, overlapped and taped at every seam, run up the foundation walls, and sealed at piers.
• Johns Manville insulation board on crawl space walls: If the board was installed without a proper drainage plane behind it, water wicks through the concrete and saturates the board from the back. Once saturated, it loses R-value and grows mold. We remove the wet board, address the drainage or grading issue, and reinstall with standoff channels that break the capillary path.

Our Johns Manville Crawl Space Encapsulation & Vapor Barrier Process

We treat every Johns Manville job as a system, not a patch job. Here’s how it goes when you call us in Santa Monica:

1. 1
   You call (424) 396-5828. A live person answers. We ask about your crawl space, your Johns Manville product, and what you’re seeing: damp insulation, standing water, musty smells, pests.
2. 2
   We inspect. A uniformed, background-checked technician comes out, checks the crawl space, measures humidity, checks the condition of your existing Johns Manville materials, and gives you an honest assessment. No trip charge inside our service county.
3. 3
   We quote upfront. You get a written, itemized price before any work starts. If you already have a written estimate from another company, bring it in. We’ll give you a free second opinion.
4. 4
   We decide on materials together. For Johns Manville replacement, we’ll show you OEM vs. quality aftermarket options. Some aftermarket vapor barriers outperform OEM at the same price point, and we’ll tell you when that’s true. We also work with Reflectix for radiant barrier applications where it makes sense.
5. 5
   We do the work right. Removal, cleaning, air sealing, insulation, vapor barrier, encapsulation, all done to spec. No shortcuts on seams, no leaving old soaked material in place.
6. 6
   We walk you through it, then guarantee it. We show you photos of the finished job. If it’s not done right, we make it right. That’s the Done Right Promise, and it’s for the life of the work.

What Johns Manville Crawl Space Encapsulation & Vapor Barrier Costs in Santa Monica

Here are the ranges we quote most often for Johns Manville work in Santa Monica:

• Vapor barrier replacement (6-mil to 10-mil, basic crawl space): $2,800 – $4,200
• Full encapsulation (vapor barrier, wall insulation, rim joist sealing, door seal): $5,500 – $9,500
• Crawl space insulation removal and replacement (Johns Manville batts or Spider): $1,800 – $3,800
• Moisture control package (vapor barrier plus dehumidifier and drainage improvements): $4,000 – $7,500
• Crawl space cleanout and prep before encapsulation: $600 – $1,500

What moves the price: square footage, crawl space height, how much old material needs to come out, and whether pests have done damage. We carry a permanent 10% discount for seniors and veterans, and $40 off any repair over $200. Call (424) 396-5828 for an exact quote. Estimates are free.

Why Santa Monica Homeowners Call Walt’s Insulation for Johns Manville Work

We’ve been working crawl spaces in Santa Monica since the early 2000s, from older bungalows near Montana Avenue to newer builds closer to the water. Walt Brenner grew up in San Antonio and learned the trade at St. Philip’s College before heading west and never quite leaving. Our company has been locally owned and owner-operated since 2000, with a published address and license number. Not a franchise, not an 800 number. When you call, a real person picks up, 24/7. The technicians who show up are background-checked and in uniform, and they know Johns Manville products because they’ve spent years pulling soggy batts and torn vapor barriers out of Santa Monica crawl spaces. As an independent Johns Manville service provider, we’re not tied to one manufacturer’s line. We install what actually works for your crawl space, whether that’s Johns Manville, Owens Corning, Rockwool, Knauf, CertainTeed, Icynene, Demilec, GreenFiber, or Reflectix. Do it right once. Everything else is just a second invoice.

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