Johns Manville Radiant Barrier Installation: The Pomona Owner’s Guide
Johns Manville radiant barrier installation in Pomona typically runs $1.80 to $2.40 per square foot installed, with most attic jobs landing between $1,400 and $2,800 depending on roof pitch and accessibility. We stock JM AP Foil-Faced and ComfortTherm radiant barrier rolls on our trucks, and we can usually inspect and quote same-day. Most Pomona homeowners discover their radiant barrier is compromised when upstairs rooms won’t cool below 78°F even after the AC runs continuously, or when they spot dust-coated, torn, or sagging foil sections during a routine attic check.
Which Johns Manville Models This Applies To
We install and replace Johns Manville radiant barrier systems across three product lines: the AP Foil-Faced series (R-8 to R-21 batts with factory-attached radiant barrier), ComfortTherm batts with kraft or foil facing, and the standalone Reflective Systems rolls (typically 500 sq. ft. rolls, 48-inch width). The critical compatibility gotcha in Pomona’s 91766, 91767, and 91768 ZIP codes is matching the existing facing type - kraft-faced batts installed in 2015-2019 construction often delaminate in our inland heat, and swapping to foil-faced without verifying attic ventilation rates can trap moisture against roof decking.
Identification is straightforward: check the printed tape strip on any exposed batt edge for the Johns Manville logo and R-value, or measure roll width and note whether the facing is perforated (breathable) or solid vapor barrier. For OEM-versus-aftermarket, we source JM direct for batt replacements to maintain original fire ratings and warranty chain, but for standalone radiant barrier rolls we also stock Reflectix as a quality equivalent when the application is non-conditioned attic space only. We never mix facing types within the same roof plane - that’s a code violation that will fail Title 24 compliance on any permitted work in Los Angeles County.
Signs Your Johns Manville Radiant Barrier Installation Is Failing

- Upstairs rooms stay hot past 9 PM. The radiant barrier’s emissivity has degraded - the foil surface oxidized or collected dust - so it’s no longer reflecting 95% of radiant heat back toward the roof deck. In Pomona’s climate, this shows up first in south-facing bedrooms.
- Visible tears, sagging, or batts pulled from top plates. Attic heat cycling and rodent activity stress the facing adhesive. We see this most in pre-1980s homes near Ganesha Park where original kraft facing has become brittle.
- Water stains on ceiling drywall below the attic. A perforated radiant barrier installed where a solid vapor barrier was required allows winter moisture migration. The facing type must match the assembly’s drying direction.
- AC runs 20+ minutes longer than neighbors’ homes of similar age. Your cooling load calculation assumed a functioning radiant barrier. When it fails, the roof deck radiates heat into conditioned space all afternoon.
- Blower-door test shows high attic bypass leakage. Radiant barrier alone doesn’t stop air leaks - and in many Pomona ranches, we find the barrier was installed over unsealed top plates, so conditioned air escapes around the material entirely.
Before
AfterReplacement Cost & What’s Included
| Component | Typical Range (Pomona) |
|---|---|
| JM AP Foil-Faced batt removal + replacement | $1.80 - $2.20 / sq. ft. |
| Standalone radiant barrier roll (new install or overlay) | $1.40 - $1.90 / sq. ft. |
| Attic air sealing (top plates, cans, penetrations) - prerequisite | $450 - $850 (typical 1,200 sq. ft. attic) |
| Blower-door test (before/after) | Included on applicable jobs |
What drives the range: roof pitch above 6/12 adds labor time, limited attic access (hatch under 22 inches square), and whether we find existing insulation that must be removed first. Every job gets a Written Price Before Any Work Starts under Haven Standard Clause 1 - flat price, written scope, written warranty before anyone lifts a tool. The 365-Day Done Right Promise covers installation workmanship; materials carry manufacturer’s warranty direct.
DIY or Call Us?

What you can safely check: confirm your attic hatch is sealed, look for obvious tears or sagging from the hatch opening with a flashlight, and photograph any product labels you can reach. Do not walk the attic - many Pomona homes built 1945-1975 have 2×4 ceiling joists spaced 24 inches on center with no decking, and a misstep puts you through the drywall.
Where DIY goes wrong: radiant barrier facing type must match the assembly’s vapor profile, and installing the wrong one traps moisture. More critically, working in an unventilated attic during Pomona’s summer months creates heat-stress conditions that send homeowners to the ER annually. We carry respirators, hydration protocols, and thermal monitors for a reason. Seal the leaks first. The insulation is just the last layer of the answer. Call (562) 242-7569 and we’ll run a blower-door test to show you where the air is actually escaping before we quote any material.
FAQs
In Pomona’s inland heat - 90+ days per year over 90°F - foil-faced radiant barriers maintain effective emissivity for 15 to 25 years if the attic stays ventilated and dust-free. Dust accumulation is the silent killer; we see 30% performance loss in attics near the 10 Freeway corridor within 8 years due to particulate loading. Call (562) 242-7569 for an attic inspection and we’ll show you current condition with our documented photo record.
Small tears in standalone foil rolls can be taped with foil tape, but this is a temporary fix - the emissivity loss is usually systemic. Batt products with delaminated facing require replacement; the facing is integral to the product’s thermal performance and fire rating. We offer free second opinions on any written estimate if you’re weighing repair versus replace.
Most Pomona attic radiant barrier replacements are completed in one day, assuming air sealing is done first. A typical 1,500 square foot attic with removal of degraded material, sealing, and new JM installation takes 6 to 8 hours. We deliver your Documented Photo Record and before-and-after blower-door numbers before we leave.
Yes - we carry JM AP Foil-Faced batts in common R-values and 48-inch reflective rolls on every Pomona-area truck. For less common widths or specialty facings, we pull from our Ontario warehouse with same-day availability. Topside Attic Insulation Pomona is an independent service provider, not affiliated with Johns Manville.
Written by Wes Okafor, Owner, Topside Attic Insulation Pomona at Topside Attic Insulation Pomona, serving Pomona and nearby areas.