Johns Manville Wall Insulation in Santa Monica: What to Know First
Johns Manville wall insulation work in Santa Monica typically runs $1.80 to $4.50 per square foot depending on whether we’re doing drill-and-fill injection into existing walls or insulating open cavities during a remodel. Most jobs are done in one day, sometimes two for larger retrofit projects. We’re an independent Johns Manville service provider, not a factory dealer, which means we tell you straight when a JM product is the right call and when something else fits better. If you own a Santa Monica home with Johns Manville insulation already in the walls, or you’re planning to put it in, call us at (424) 396-5828. You’ll get a live person, not a phone tree.
How Johns Manville Products Fail - and How We Fix Them
We’ve been inside enough Santa Monica walls to know exactly where Johns Manville materials hold up and where they don’t. Here’s what we actually see:
- ComfortTherm batts with torn kraft facing. The kraft paper vapor barrier on ComfortTherm batts gets shredded during sloppy installs, especially around electrical boxes and plumbing penetrations. Once that facing is compromised, moisture from Santa Monica’s marine air gets into the fiberglass and the R-value drops. We pull the damaged batts, re-frame the cavity properly, and reinstall with the facing sealed tight. If the tear is minor, we’ll tape it with JM-approved facing tape rather than replacing a perfectly good batt.
- Spider blown-in fiberglass settling in closed walls. Johns Manville’s Spider insulation works great when installed with the right binder and moisture content, but we’ve opened walls in older Santa Monica bungalows where it settled six to eight inches in ten years. That gap at the top of the wall cavity is a thermal hole. Our fix is dense-packing the cavity with JM Spider or a compatible blown-in product at the correct density, not just topping it off. Topping it off hides the problem for a year; dense-packing solves it.
- AP Foil-Faced polyiso with air gaps behind it. In retrofit exterior wall applications, Johns Manville AP Foil-Faced sheathing sometimes gets installed with small gaps between the foam board and the stud cavity. Those gaps let air move behind the insulation, which kills the effective R-value. We pull the board, flash and seal the cavity properly, and reinstall. It’s tedious work, but it’s the difference between insulation that insulates and insulation that just looks like it does.
- Formaldehyde-free fiberglass losing loft after rodent activity. Santa Monica has rats. They love fiberglass. When rodents nest in JM batts, they compress the material and leave waste throughout the cavity. We see this most often in crawlspace-adjacent walls and around garage headers. The fix is removal, sanitizing the cavity, sealing the entry point, and reinstalling fresh Johns Manville material. Leaving old contaminated batts in place is a health issue, not just an efficiency one.
- Moisture-compromised MR-Faced batts in bathrooms and laundry walls. The moisture-resistant facing on JM MR batts isn’t waterproof. In Santa Monica homes near the beach, we regularly find these batts saturated because someone skipped a proper vapor barrier or the exterior stucco is cracked and letting fog drift in. Wet fiberglass loses nearly all R-value and breeds mold. We replace the batts, address the moisture source, and recommend the right facing for the specific wall assembly.
Our Johns Manville Wall Insulation Process
Here’s how a typical Johns Manville wall insulation job goes with us, from the first call to the final look-over:
- 1
You call, a person answers. We talk through what you’re noticing: drafts, hot rooms, noise, energy bills. We’ll ask about the age of the house and whether you know what’s in the walls now.
- 2
We inspect the wall cavities. We use a borescope through a small access point to see what’s actually in there: what type of Johns Manville product, what condition, what depth. In Santa Monica’s older homes, surprises are the rule, not the exception.
- 3
We give you a written price before work starts. No vague ranges. The number on the estimate is the number you pay. We’ll also tell you if another brand like Rockwool or CertainTeed would serve you better for your specific situation. We install them all.
- 4
We do the work. For drill-and-fill, we drill small exterior or interior access holes, dense-pack the cavity with JM Spider or equivalent, and plug and finish the holes. For open cavities in remodels, we install batts with the facing oriented correctly for Santa Monica’s climate zone.
- 5
We test and verify. We check cavity fill with thermal imaging where it makes sense and walk the job with you before we leave.
- 6
You’re covered. Every job carries the Done Right Promise, our lifetime workmanship guarantee. If it’s not done right, we make it right. No runaround, no arguments.
What Johns Manville Wall Insulation Costs in Santa Monica
Here are honest price ranges for common Johns Manville wall insulation scenarios in Santa Monica:
- Drill-and-fill with JM Spider in existing walls: $2.50 to $4.50 per square foot of wall area, including plugging and finish work.
- Open-cavity ComfortTherm batt install during remodel: $1.80 to $3.20 per square foot.
- Rodent damage remediation plus re-insulation: $3.50 to $6.00 per square foot, depending on contamination level and access difficulty.
- Exterior wall insulation with AP Foil-Faced sheathing: $3.00 to $5.00 per square foot installed as part of a re-siding project.
What moves the price: wall height, access (interior vs. exterior drilling), existing insulation removal, and whether we’re matching an existing Johns Manville system or starting fresh. Older Santa Monica homes with lath-and-plaster walls are slower to work on than drywall. You’ll know your exact number before we start. Call (424) 396-5828 for a free estimate.
Why Santa Monica Homeowners Call Walt’s Insulation for Johns Manville Work
Walt Brenner started this company in 2000 after learning the trade at St. Philip’s College, and he’s been crawling through Santa Monica walls ever since, from the older bungalows near Montana Avenue to newer builds closer to the water. He knows what the marine air off the Pacific does to a wall cavity if the envelope isn’t tight. That’s why we run a business with a published address, a real license number, and a live person on the phone 24/7, not an answering service in another state. If we install Johns Manville and it fails due to our workmanship, the Done Right Promise covers it for as long as you own the house. We also work with Reflectix and other brands, so we’re not married to one product line. Do it right once. Everything else is just a second invoice.
FAQs
No, properly installed Johns Manville insulation carries the manufacturer’s material warranty regardless of which licensed contractor installs it, and our workmanship is covered separately by our lifetime Done Right Promise. As an independent Johns Manville service provider, we follow JM installation specs so the product warranty stays intact. Call (424) 396-5828 if you want us to check your existing warranty paperwork before we quote the job.
In most Santa Monica homes, repairing specific problem areas costs 40 to 60 percent less than a full replacement, but if the insulation is wet, rodent-contaminated, or settled more than three or four inches, replacement is the honest recommendation. We’ll show you what we’re seeing with a borescope before you spend a dollar. Get a free second opinion on any written estimate you’ve received.
Most drill-and-fill jobs on a standard Santa Monica home are completed in one day. Larger homes or jobs requiring removal of old insulation take two days, sometimes three if we’re also air sealing. We’ll give you a firm schedule when we give you the price, and there’s no trip charge inside our service county.
For closed existing walls, we recommend dense-packed JM Spider because it fills irregular cavities in older Santa Monica framing better than batts. For open walls in remodels, ComfortTherm with the right facing orientation handles our humidity swings well. The honest answer depends on your wall assembly, and we’ll tell you if a non-JM product like Rockwool makes more sense for your specific house.
Yes, we match existing Johns Manville products by type and R-value so the thermal performance is consistent across the wall. In some older Santa Monica homes, the original product is discontinued, in which case we’ll recommend the closest current equivalent and explain the difference before ordering anything.
Contact Walt’s Insulation
If you’re in Santa Monica and need Johns Manville wall insulation installed, repaired, or evaluated, call us at (424) 396-5828. A live person answers, day or night. We’ll give you a straight answer, a written price, and no pressure. Seniors and veterans always save 10 percent. That’s just how we do business.
Written by Walt Brenner, Owner, Walt’s Insulation at Walt’s Insulation, serving Santa Monica and nearby areas.