Johns Manville Attic Insulation: The Los Angeles Owner’s Guide
We stock and install Johns Manville attic insulation across Los Angeles, with most full-attic blow-in jobs running $1,450 to $3,200 installed depending on square footage and current R-value. Same-day or next-day installation is available in most LA neighborhoods, and we carry the full Johns Manville line on our trucks: ComfortTherm batts, Climate Pro blown-in fiberglass, and Attic Protector loose-fill. Homeowners usually discover a problem the same way every summer: the upstairs bedrooms won’t hold temperature, the AC runs constantly, and the July electric bill lands like a punch. Sometimes it’s not a failure at all, just old R-19 batts in a city that needs R-38 or higher to handle the heat.
If you’re here because someone told you your Johns Manville insulation needs replacing, or you’ve looked up at your own attic and wondered whether what’s up there is still doing its job, this page will give you the straight answer on what it costs, what fails first, and whether it’s worth doing yourself.
Which Johns Manville Models This Applies To
Johns Manville makes three main attic insulation lines, and we install all of them. ComfortTherm is their kraft-faced batt insulation, wrapped in a plastic film that keeps the fiberglass contained. Climate Pro is their blown-in loose-fill fiberglass, typically the best value for an open attic floor. Attic Protector is the premium loose-fill, formulated with a slightly higher R-value per inch and better handling characteristics for tight spaces.
Here’s what matters for compatibility: Johns Manville batt insulation follows standard 16-inch and 24-inch joist spacing, but the kraft facing must face the living space in an attic floor install. If your previous installer flipped it, which we see more often than we’d like in Los Angeles, the vapor direction works against your LA climate and traps moisture against the drywall. Blown-in products are model-specific at the equipment level, not the compatibility level. Fiberglass loose-fill goes in with any standard blowing machine; the difference between Climate Pro and Attic Protector is coverage per bag, which affects your final cost by a few hundred dollars on a large attic. One gotcha worth knowing: if your attic has existing Johns Manville batts from before 2000, they’ll measure as R-19 or R-13. Current California Title 24 energy code wants R-38 minimum in most of Los Angeles. We don’t just top off with new fiberglass; we document what’s there, note what needs to come out, and write the R-value target on your estimate before any work begins.
Signs Your Johns Manville Attic Insulation Is Failing
- Upstairs rooms run 8 to 12 degrees warmer than downstairs. This is the classic symptom in Los Angeles ranches and two-story homes. When fiberglass insulation settles, compresses, or was under-installed in the first place, the heat load from the attic simply overpowers the AC in the upper half of the house.
- Your cooling bill keeps climbing year over year. LA summers are getting hotter, but a house with R-38 or better in the attic shouldn’t see a dramatic jump. If your July usage trend looks like a staircase, the insulation has likely settled or shifted.
- You can see the joist tops through the existing insulation. In an attic floor, the joists should be fully covered by loose-fill. If the 2×6 or 2×8 tops are clearly visible, your effective R-value has dropped below what the product label says.
- Rodent or water damage has matted down sections. Rats love fiberglass, and a leak around a roof penetration soaks the insulation and crushes its loft. Compressed fiberglass loses most of its insulating ability; the manufacturer’s R-value only holds at full thickness.
- Dust from the attic is migrating into the house. If you see fiberglass fibers collecting around can lights or ceiling fixtures, the insulation envelope has gaps, and air is moving through them. That’s both an energy problem and an indoor air quality issue.
Replacement Cost & What’s Included
For Los Angeles attics, here’s what we quote most often, including labor, cleanup, and disposal of the old material if needed:
- Blown-in Climate Pro, 1,000 sq ft, R-38: $1,450 to $1,900
- Blown-in Attic Protector, 1,000 sq ft, R-38: $1,700 to $2,200
- Full batt replacement, ComfortTherm R-38: $2,200 to $3,200 depending on joist spacing and access
- Remove old fiberglass and re-insulate: add $400 to $750, mostly for the vacuum-out labor and disposal runs
Every quote is written down before the first bag comes off the truck. That’s the Aspen way, and it’s non-negotiable. The price covers the material, the install, the cleanup, and a full 365-Day Done Right Promise: if something’s not right within a year, we come back and fix it free. No re-trip charge, no argument. You’ll also know exactly who’s walking in your door, because we send the technician’s name and photo before the visit. Same person, marked uniform, photo ID at the door. That’s the Threshold Standard, and we’ve held it since 2002.
DIY or Call Us?
You can safely check your attic insulation level yourself. Grab a flashlight, poke your head up there, and look for joist tops. If you see them, the insulation is thin. That check costs you nothing and tells us a lot on the phone.
Where DIY goes wrong is the actual install. Blowing fiberglass looks easy on video, but running a commercial blower in a 130-degree LA attic while walking joists and managing the hose is honest work that shows up in coverage quality. Batt installation looks foolproof until someone cuts around a recessed can light wrong and creates a fire hazard, or blocks the soffit vents and turns the attic into an oven. We also see homeowners buy batts, install them, and miss the California vapor-barrier direction entirely, which costs them a drywall repair down the road. If you’d rather skip the August attic sauna, call us at (213) 376-3824 and we’ll handle it from start to finish.
FAQs
Fiberglass insulation itself doesn’t wear out the way a mechanical part does, but blow-in loose-fill loses R-value over 15 to 25 years as it settles, absorbs dust, and gets disturbed. In a Los Angeles attic, the bigger factors are heat, rodents, and roof leaks, which can cut the effective life to a decade or less. Call (213) 376-3824 and we’ll tell you what yours has left.
Usually yes, as long as the existing material is dry, not matted, and not full of rodent waste. We top off with blown-in fiberglass to reach the target R-value. If the old insulation is damaged or contaminated, it has to come out first. We’ll tell you which one applies after a quick look.
Most Los Angeles attics are done in one day. Blow-in jobs typically run 4 to 6 hours, batt removal and replacement 6 to 8 hours. We bring enough material on the truck to handle any attic up to 2,500 square feet, so there’s no waiting on a second run.
We stock Climate Pro, Attic Protector, and ComfortTherm on our trucks year-round, along with materials from Owens Corning, Knauf, Rockwool, CertainTeed, Icynene, Demilec, GreenFiber, and Reflectix. The right product goes in based on what your attic needs, not what we have left over. Call (213) 376-3824 and we’ll tell you exactly what we’d put in yours.
Get a Straight Answer on Your Attic
Garrett Sloane likes to say: “Tell me what’s in your attic and I’ll tell you exactly what it needs, no guesswork, no upsell.” That’s how we quote. If you suspect your Johns Manville insulation is done, call (213) 376-3824 and we’ll walk you through what’s up there, what it costs to fix, and who’ll be at your door. No pressure, just a real answer from someone who’s been doing this in Los Angeles since before the 2022 code changes made R-38 the floor, not the ceiling.
Written by Garrett Sloane, Owner, Aspen Attic Insulation Los Angeles at Aspen Attic Insulation Los Angeles, serving Los Angeles and nearby areas.