Designing for Gypsum Board Abuse Resistance

Within the last decade, gypsum board manufacturers have focused a great deal of research on understanding the nature of abuse that gypsum partitions may face during day-to-day service life.

This analysis has led to an understanding that there are three distinct components of abuse resistance. They are:

• Surface Damage – This encompasses abrasion or incidental indentation of the partition face from high traffic under normal use.
• Penetration – This is defined as penetration through the facing material into the stud cavity resulting from the impact of a blunt object (such as a kick or a hammer blow) or from a sharp object (such as a screwdriver or a knife). It also includes a blow from a softer object that covers a large surface area of the wall. When penetrated, systems without a stud cavity tend to undergo failure of the entire partition.
• Security – This is a breach of the entire assembly from either forced entry or ballistics.

To aid architects in determining which gypsum panel designs best meet these various abuse-resistance conditions, the following abuse categories have been developed:

• Category One (Light Duty) – A basic upgrade of standard drywall that provides improved resistance to incidental surface and impact damage.
• Category Two (Moderate Duty) – Ideal for areas such as multifamily stairwells and retail corridors that require an upgraded resistance to incidental surface and impact damage.
• Category Three (Heavy Duty) – Ideal for freight elevator walls and other areas that require resistance to heavy surface and impact damage.
• Category Four (Extreme Duty) – For even stronger protection against heavy surface and impact damage.
• Category Five (Security) – For protection against forced entry and ballistics.

For a typical office building, the shaft wall design may require a category one or two level of abuse resistance. Hospitals and other institutional facilities may require heavy to extreme abuse resistance (categories three or four). And where security is a consideration, category five abuse resistance may be required. One such building, the Broward County Judicial Center, in Broward County, Fla., was designed by Michael Schiff & Associates in the early 1990s with shaft walls made from high-strength solid plaster. As security in building design continues to grow in importance, wall security testing recently promulgated by the U.S. Department of State (ST-STD-01.01 and ST-STD-01.02) may be of particular interest.

One Cautionary Note:

When designing shaft walls for abuse resistance or for any other secondary consideration, life safety considerations should never be compromised. Independently verified system performance always comes first.