Lightweight Mold Tough line at 1.35 lb/sq ft nominal density per USG
Key features
Moisture- and mold-resistant papers with moisture-resistant gypsum core per USG
Tapered long edges for conventional joint finishing per USG
Technical specifications
| R-Value | 0.45 |
|---|---|
| Thickness | 0.5 in |
| Width | 48.0 in |
| Length | 120.0 in |
| Coverage | 40.0 sq ft/pack |
| Material | Moisture-resistant gypsum core with moisture- and mold-resistant recycled papers (UltraLight Mold Tough per USG) |
| Fire rating | Noncombustible gypsum core per typical gypsum-board listings; UL classification for surface-burning characteristics and noncombustibility per USG. Not a Type X (firecode) panel unless a separate Type X SKU is specified—verify UL design listings for rated assemblies. |
| Sound rating | Acoustic performance is assembly-dependent; gypsum finish layers contribute to STC in tested partition assemblies (ASTM E90). |
| Density | Nominal 1.35 lb/sq ft panel weight per USG Mold Tough UltraLight specifications |
| Construction type | ASTM C1396 for 1/2 in. water-resistant gypsum wallboard and 1/2 in. exterior gypsum soffit board categories per USG Mold Tough UltraLight listings |
| Application area | Interior walls and ceilings where enhanced moisture and mold resistance is desired—bath, laundry, and similar areas per typical use; follow USG installation and finishing guidance |
Product details
Ten-foot Mold Tough stock helps moisture-sensitive elevations stay on the Mold Tough paper system while reducing mid-height seams compared with eight-foot lifts—ideal when framed heights land just over ninety-six inches and logistics accept the longer module.
Coverage is forty square feet per sheet; at 1.35 lb per square foot nominal per USG, plan near fifty-four pounds per sheet before fasteners and lifts, noticeably heavier than standard UltraLight but still lighter than many traditional moisture boards at similar thickness.
Documentation parallels the Mold Tough UltraLight story: ASTM C1396 water-resistant categories, ASTM D3273 references, UL classification, and GREENGUARD Gold—keep PDF revision dates with your submittal so inspectors see the current language.
Price-check against your distributor; YEARS may carry proportional estimates from shorter modules—live quotes win every bid.
Always dry-stack indoors when possible; wet kraft or damaged mold-resistant papers compromise both finish quality and the marketing claims you relied on in the spec.
Documents & certifications
Technical data sheet
Manufacturer-tested R-value, coverage, fire notes, and handling—use for submittals, RFIs, and field QA.
Download PDF (opens in new tab)Certifications & compliance
GREENGUARD Gold; UL classification (surface burning / noncombustibility per USG); ASTM C1396; ASTM D3273 mold-surface test per USG
Frequently asked questions
What makes Mold Tough different from standard UltraLight?
What makes Mold Tough different from standard UltraLight?
UltraLight Mold Tough uses a moisture-resistant gypsum core and moisture-/mold-resistant papers; USG states ASTM D3273 chamber testing and ASTM C1396 compliance for the water-resistant board categories listed on its product page.
Can I skip cement board in a wet wall?
Can I skip cement board in a wet wall?
That is an assembly and code decision. Mold Tough is marketed for enhanced moisture/mold resistance, but showers and tub surrounds often still require systems listed for wet areas—confirm with USG details, TCNA guidance, and your AHJ.
Is this panel Type X?
Is this panel Type X?
Not automatically. For fire-resistance-rated assemblies, use the exact board type and UL assembly referenced in the design. Do not substitute Mold Tough UltraLight for Type X unless the listing explicitly allows it.
What weight should crews plan for?
What weight should crews plan for?
USG lists nominal 1.35 lb/sq ft for UltraLight Mold Tough 1/2 in. Multiply by sheet area for nominal pounds before lifts and stocking.