FREQUENTLY ASKED QUESTIONS

Fire (25)

What is the difference between Class A and Firecode® branded materials?

Class A signifies that a panel attained a flame spread index of 25 or less (based on 100 for untreated red oak) when tested in accordance with the Standard ASTM E 84. The Firecode® brand signifies that the panel has been classified as a protective membrane in a floor-ceiling or roof-ceiling assembly in accordance with the Standard ASTM E 119. All Firecode® protective membranes offered by USG have attained a Class A rating.

Does the ceiling tile and grid system alone provide a fire-rated assembly?

No. The ceiling system achieves a time rating based on the entire assembly which includes roof deck or floor deck assembly.

Industry Terms and Definitions (15)

Why is CAC important?

CAC is important when there is a need for privacy between spaces.

What is CAC?

CAC stands for Ceiling Attenuation Class. It is the measure of the blocking of sound through one ceiling plane, into the plenum above, and back through the other ceiling plane to an adjacent space.

Installation and Application (184)

Can fiberglass tape be set with drying-type compounds?

No. When using fiberglass tape, only setting-type joint compounds like Sheetrock® Brand Durabond® and Sheetrock® Brand Easy Sand™ should be used for the first coat over the tape. Ready-mixed drying-type compounds can be used for subsequent finishing coats.

What is the best way to store ready-mix compound for another use?

Clean sides and lid of container so no dried compound falls into the mixture. Level joint compound surface with a knife and cover container tightly. If storing, cover leveled surface of joint compound with approximately 1/2" of clean water and cover container tightly. Pour off water before reusing joint compound. Do not store in direct sunlight and protect from extreme heat and cold. The shelf life of an unopened container is up to nine months under proper storage conditions.

Product Specific (99)

How many acoustical panel types does USG offer?

USG offers four major types of acoustical panels as well as Gypsum based panels for special applications. They are: Wet-Felted, Cast, "X" Technology and Fiberglass.

What is the best way to store ready-mix compound for another use?

Clean sides and lid of container so no dried compound falls into the mixture. Level joint compound surface with a knife and cover container tightly. If storing, cover leveled surface of joint compound with approximately 1/2" of clean water and cover container tightly. Pour off water before reusing joint compound. Do not store in direct sunlight and protect from extreme heat and cold. The shelf life of an unopened container is up to nine months under proper storage conditions.

Residential (14)

What is the best way to store ready-mix compound for another use?

Clean sides and lid of container so no dried compound falls into the mixture. Level joint compound surface with a knife and cover container tightly. If storing, cover leveled surface of joint compound with approximately 1/2" of clean water and cover container tightly. Pour off water before reusing joint compound. Do not store in direct sunlight and protect from extreme heat and cold. The shelf life of an unopened container is up to nine months under proper storage conditions.

What is the best way to remove the protective masking on the back of USG Sheetrock® Brand Pre-masked L-Trim?

Relax the serrated edge by pre-creasing or folding the strip. This ensures smooth removal of the masking and results in a clear tear that will not damage the trim.

Specialty Uses (13)

What is the minimum NRC recommended for open office plan environments?

It is best to use a minimum of .70 NRC and up to .80 - .90 NRC panel for this type of application.

What does gypsum do for my soil?

Gypsum will provide calcium and sulfur to your soil and won't buffer the pH of your soil like limestone products. Gypsum can also help open air and moisture channels in the soil, improving soil struture and reducing run-off. Gypsum can also act to counter damage caused to plants by salt.

Sustainability (3)

Isn’t fly ash bad for concrete and isn’t it a potential hazardous product?

Fly ash often is used as a filler in concrete. When used at excessive levels, fly ash and concrete has been cited as one of the reasons for excessive moisture in concrete slabs.

In Durock™ EcoCap™ Self-Leveling Underlayment, the fly ash is not used as filler but rather as a source of aluminum and silicon in the geopolymer reaction that takes place. In this case, the fly ash contributes significantly to the strength, self drying and setting characteristics of the product due to the geopolymer reaction.

What is the recycled content of Durock™ EcoCap™ Self-Leveling Underlayment?

75% of the cementitious binder is recycled material.

Technical (77)

Why do stains appear when retexturing a wall or ceiling?

Over time stains settle into a wall or ceiling. When that area is retextured the stains photograph through causing a yellowing or browning effect. The best way to prevent staining is to apply a stain blocker, primer, and sealer.

What is the difference between Class A and Firecode® branded materials?

Class A signifies that a panel attained a flame spread index of 25 or less (based on 100 for untreated red oak) when tested in accordance with the Standard ASTM E 84. The Firecode® brand signifies that the panel has been classified as a protective membrane in a floor-ceiling or roof-ceiling assembly in accordance with the Standard ASTM E 119. All Firecode® protective membranes offered by USG have attained a Class A rating.

Product Storage (13)

How far in advance can I order ceiling panel before installation?

Storage time of materials at the job site should be as short as possible, and environmental conditions should be as near as possible to those specified for occupancy. Excess humidity during storage can cause expansion of material and possible warp, sag, or poor fit after installation. Chemical changes in the mat and/or coatings can be aggravated by excess humidity and cause discoloration during storage, even in unopened cartons. Cartons should be removed from pallets and stringers to prevent distortion of material. Long-term (6-12 months) storage under uncontrolled environmental conditions should be avoided.

What is the shelf life of a texture product?

The shelf life of an unopened container is up to nine months from the date of manufacture under protected storage conditions.

Warranty (6)

What is the warranty for USG Sheetrock® Brand Paper-Faced Metal Tape-On and Nail-On Bead and Trim?

The warranty is effective for 30 years from the date of the installation in the structure. See complete warranty for details:

What is the standard warranty of grid?