All Things Gypsum
Common Myths About Gypsum Board
The following myths that arise from time to time relative to gypsum board, other areas of the gypsum industry, and business in general can be dealt with and put to rest for what they are: myths.
Tall talesMyth #1: The gypsum industry doesn’t recycle. For more than half a century, visionaries in the gypsum industry have served as environmental stewards. Gypsum board manufacturers have developed the technology to recycle in-plant production wastes; many older plants have also been fitted to recycle new construction gypsum board waste that is returned to the plant for this purpose.
Synthetic gypsum is chemically identical to regular gypsum ore but is a byproduct from other manufacturing processes, such as the manufacture of paint or the desulfurization of flue gases in fossil-fueled power plants. By using what would otherwise be a waste product, the industry reduces the stream of solid wastes going to landfills and extends the natural gypsum ore reserves. Products that contain synthetic gypsum are manufactured to the same standards and quality as products made from naturally occurring sources. The gypsum industry continually strives to support manufacturing and construction practices that help to mitigate the impact of building on the environment.
Myth #2: The face paper on gypsum board has changed. Paper manufactured from recycled sources has been used on gypsum board for more than 40 years. Long before recycling became popular, the gypsum industry was recycling newspaper and other paper products to manufacture the face and back paper for gypsum board. Today, nearly 100 percent of the paper used in gypsum board production is made from post-consumer waste paper. The next time someone claims that a bad paint job is due to “gypsum board manufactured with face paper made from old newspapers,” take a moment to explain the facts: Maybe the paint doesn’t cover walls like it used to but it’s not a change in the gypsum board paper that’s causing the difficulty.
Myth #3: You can’t install gypsum board outside—it will freeze! A common misperception about gypsum board is that it can’t be installed where it might be exposed to cold temperatures, such as the underside of a soffit on the exterior of a building. The water that provides gypsum board with its natural fire resistance is chemically combined in the gypsum crystal and is unaffected by freezing temperatures.
Gypsum board can be installed where it is exposed to occasional cold temperatures as long as the board is located in a weather-protected location and does not become wet. However, due to normal expansion and contraction caused by the weather, long expanses of gypsum board exposed to outside temperatures on an ongoing basis may need to have “control” joints incorporated.
Myth #4: Once the building is enclosed, you don’t have to worry about water damage. Unwanted water or unintended high levels of moisture can cause damage in all types of structures. Widespread awareness currently surrounding the undesirable effects of moisture in buildings makes it imperative that we understand that water damage to gypsum board and other construction materials poses a greater problem than just a temporary concern during the construction phase.
Exposure to water during the construction period can cause problems in buildings but is not always the main source of serious water damage. The insurance industry has reported that the overwhelming majority of water damage claims (including mold on walls, floors, and ceilings resulting from water or moisture) is the result of leaks in existing buildings. Leaking roofs and pipes have been identified as the leading sources of water from which damage and mold claims result.
Myth #5: If the walls are heated, joint compound will dry faster. All contractors walk a fine line when it comes to finishing the drywall with compound. When the need to finish a job on time is coupled with inconsistent or extreme environmental conditions, pressure to accelerate the joint compound application process can become overpowering. However, artificially overheating drywall surfaces or applying joint compound over a layer that has not had sufficient time to dry, may create a potential liability situation that is unnecessary. Superheating a surface finished with compound, or applying wet compound to a joint not yet dry, may not cause an immediately discernable problem; however, it will increase the possibility that joint problems will surface in the future. The preferred solution is to allow joint compound to dry naturally under suitable environmental conditions.
Myth #6: Gypsum board is soft; masonry is required to build a “real” wall. Gypsum board is a sturdy and durable material. A two-sheet application of 5/8-inch thick type-X gypsum board applied to 2x4 wood studs will resist the impact of a 50-pound bag of sand dropped from a height of almost 6 feet. Adding an extra layer of gypsum board to a single-layer system will increase the impact resistance by more than 100 percent.
This means that the durability of basic interior partitions can be improved by the addition of one more layer of gypsum board; a coat of veneer plaster will make partitions even more durable and attractive, and can greatly reduce the project’s finishing schedule. Contractors who work with architects may wish to emphasize this cost-effective feature because it means that multi-layer gypsum board systems can be used in public areas to provide an economical alternative to masonry materials, while generating savings for the building owner.
Myth #7: Because of its paper face, gypsum board can’t be used in noncombustible construction. Model building codes typically require materials to comply with the extremely difficult ASTM E 136 test to be considered noncombustible. Although the gypsum core will not burn, because of its paper facing, gypsum board technically cannot meet the stringent requirements of this test. Alternative standards are also accepted by building codes to determine the approval of building materials that can be used in rated construction.
These alternative criteria require the core of the material to pass the E 136 test and the material’s surfacing to be less than 1/8-inch thick while possessing a very low flame spread rating. Gypsum board meets these alternate criteria because its core complies with the E 136 requirements and its thin paper facing has a flame spread that is considerably less than the 50 that is allowed.
Myth #8: It’s all wallboard. A couple of columns ago, I discussed the variety of generic products produced by the gypsum manufacturing industry. This relatively long list of specific product names can at first be confusing; however, if gypsum board products are to be used correctly and in places where they are allowed, the terms and definitions must be understood.
For example, gypsum wallboard, gypsum sheathing board, gypsum lath, gypsum shaftliner board, gypsum base for veneer plasters, water-resistant gypsum backing board, exterior gypsum soffit board, predecorated gypsum board and gypsum ceiling board are all distinct products that are included in the family of paper-faced products properly known as gypsum board. In addition to gypsum board, the gypsum industry manufactures products that may be unfaced or faced with something other than paper. These and the gypsum board family of products are all known as gypsum panel products—an umbrella term that includes all the unfaced and nonpaper-faced products as well as all gypsum board products.
Myth #9: Local politics don’t influence how you do business. As the representative of the gypsum board manufacturing industry in the United States and Canada, the Gypsum Association actively participates at the national, state/provincial, and local levels of building code and standards deliberations. We continually search for new and effective ways to become more involved in these processes.
It is a way to look after the best interests of our members and to learn more about specific issues. Contractors obviously have the same right as citizens to be in touch with legislators, both at the local and federal levels. It is one of the easiest and most effective ways to become involved in the legislative process. Not only that, but public officials actually value the information provided by their constituents, i.e., taxpayers, contributors to the state’s economy, and the people most likely to be affected by legislation under consideration.
Legislators, mayors and other public officials are intimately involved with issues in their communities—and the ability of local business people to work effectively in their community directly relates to the economics of the area. Attending city- or county-level council meetings or occasionally state-level legislative sessions will help develop important contacts with the officials and familiarity with the issues. Sometimes, a relationship with a local official will lead to an entree at a higher level, even the federal level. Thomas Jefferson once said, “The government is the strongest of which every man feels himself a part.” Becoming involved locally can be worthwhile for contractors, their companies and their future.
Help the gypsum industry maintain its reputation as a great industry: Help us dispel the myths wherever and whenever they materialize.