ToughRock Mold Guard Moisture Resistant Drywall
ToughRock MoldGuard Moisture Resistant Drywall Gypsum Board
Moisture-Resistant Drywall Gypsum Board

ToughRock® Mold-Guard™ Gypsum Board

  • Moisture and mold-resistant treated facings1
  • Moisture-resistant1 treated, non-combustible core (when tested in accordance with ASTM E136)
A mold-resistant wall board ideal for high-humidity interior residential and commercial applications.

Manufactured to meet ASTM C1396 Section 7; CSA-A82.27-M and Federal Specifications SS-L-30D, Type VII Grade W. ToughRock® Mold-Guard™ Gypsum Board is designed to provide extra protection against mold and mildew compared to traditional paper-faced gypsum board products. When tested, as manufactured, per ASTM D3273 (“Standard Test Method for Resistance to Growth of Mold on the Surface of Interior Coatings in an Environmental Chamber”), ToughRock Mold-Guard Gypsum Board achieved a score of 10 – the best possible score for this test.1 It’s ideal for high humidity interior areas such as kitchens, bathrooms, basements and laundry rooms. This board may be used in wet areas behind tile, such as tub and shower areas, when C1396, Section 7 is allowed by local building code in such applications.2

1The score of 10 in the ASTM D3273 test, indicates no mold growth in a 4-week controlled laboratory test. The mold resistance of any building product when used in actual job site conditions may not produce the same results as were achieved in the controlled, laboratory setting. No material can be considered mold proof. When properly used with good design, handling and construction practices, ToughRock® Mold-Guard™ Gypsum Board provides increased mold and moisture resistance compared to standard paper-faced wallboard products. However, the product is not intended for immersion in water or prolonged exposure to moisture. As with any building material, avoiding water exposure during handling, storage and installation, and after installation is complete, is the best way to avoid the formation of mold or mildew.

2Georgia-Pacific recommends DensShield® Tile Backer for tile applications in wet areas such as showers where 2006 or later IBC or IRC are referenced.

Moisture Resistance

Superior moisture resistance in high humidity interior areas


Physical Properties

nominal inches: 1/2″ (12.7 mm), ±1/64″ (0.4 mm)


nominal: 4′ (1220 mm) ±3/32″ (2.4 mm)


standard: 8’ (2440 mm) to 16’ (4880 mm) ± 1/4( (6.4 mm)


lbs/sq. ft. nominal (kg/m²): 1.7 (8.3)1

R Value

°F•ft2•hr/BTU (m2•K/W): 0. .45 (0.08)2

Humidified Deflection

10/8″ (32 mm)3

1Represents approximate weight for design and shipping purposes. Actual weight may vary depending on manufacturing location and other factors. 2Per Gypsum Association document GA-235. 3Specified minimum values are as defined in ASTM C1396.

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Product Resources

3-Part Specs
Tech Guides
Safety Data

Product FAQs

Can ToughRock® Mold-Guard™ Gypsum Board be used in wet areas?

ToughRock® Mold-Guard™ is manufactured to meet ASTM C 1396 section 7 for moisture resistant gypsum board. If your local code allows for the use of ASTM C 1396 section 7 in wet areas, then ToughRock Mold-Guard may be used in this application.

What should we do if the gypsum board gets wet?
Can ToughRock Mold-Guard Gypsum Board be used in pre-rock conditions?
How often is a control joint required?
Should gypsum board be installed vertically or horizontally?

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