All Things Gypsum: The Sustainability of Gypsum
If a program such as LEED is in effect, a project constructed under the auspices of a government entity at the local, state, or federal level will require that a new or renovated building must meet a certain level of sustainability as determined by a given point system. To be awarded a government construction contract, a bid must demonstrate that a building has been designed and will be constructed per the criteria set forth by the specified green building standard. LEED, for example, identifies three levels-Silver, Gold, and Platinum-of qualification. Other similar standards, such as the proposed Green Globes standard, use similar classification methods.
All of the green accounting schemes factor in a variety of criteria in their point systems, such as how much energy is expended acquiring, manufacturing, and delivering the materials used in a construction project; how much recycled material is incorporated into those materials; how much water will be consumed or conserved by the building, and so on.
The idea of “Sustainability” was originally intended to focus design professionals on using renewable resources, such as bamboo, turf roofing, and solar heating. However, that idea has been broadened to include using materials that are readily available and will last for the life of the building. This concept has in turn led to the science of Life Cycle Assessment which, though still in its infancy, is intended to eventually enable design professionals to determine which materials will last the longest in a particular setting with the least amount of maintenance, thus enhancing the sustainability of a new building.
So, now producers of building materials find themselves identifying and enumerating the characteristics of their wares in terms of their sustainability. Fortunately for the gypsum industry, we have plenty of ammunition for this contest, and knowing these attributes will no doubt serve the general contractor and the drywall contractor well in the days ahead.
BUILDING GREEN WITH GYPSUM PRODUCTS
Using gypsum products, primarily gypsum board but also joint treatment and gypsum plaster, can earn green points for a project in several categories:
- Recycled content
- Locally available material/transportation
- Life cycle assessment and building life service
- Construction waste diversion and on-site debris disposal
- Manufacturing facilities
Building materials must contain either pre-consumer or post-consumer recycled components, or both, to qualify for recycled content green building credits. In the 1950s, gypsum product manufacturers began recycling newsprint and other paper products to make the facing and backing paper on gypsum board and similar products. Today nearly 100 percent of the facing and backing paper on those products is recycled material.
The gypsum industry also uses the majority of the available synthetic gypsum produced in the United States – a by-product of the flue gas desulphurization process used to remove sulphur dioxide produced by the burning of fossil fuels for power generation and other smokestack industries-in the manufacture of gypsum products. Much of the synthetic gypsum, which is chemically identical to natural gypsum, would otherwise wind up in the nation’s landfills were it not used in the manufacture of gypsum products.
LOCALLY AVAILABLE MATERIAL/TRANSPORTATION
Green building standards offer credits for using locally available (indigenous) building materials. Some standards also offer credits for transporting those materials using a means other than trucking.
Historically, gypsum manufacturing facilities have been sited near the source of the gypsum ore or near a port that facilitated over water shipment of ore. The finished products were then sent via rail or truck to customers or distribution points. With the increased use of synthetic gypsum, manufacturing plants are now increasingly located closer to market areas, particularly in the eastern United States, where they can transport their finished goods by rail, which is perhaps the most energy efficient means for moving products over medium to long distances.
LIFE CYCLE ASSESSMENT AND BUILDING LIFE SERVICE
Life cycle assessment uses multiple criteria to evaluate how a building material will perform for the life expectancy of the building. This process enables specifiers to compare how various building materials will impact the environment and how expensive use of the different materials for the same application will likely be.
Gypsum products score very well in life cycle cost analyses because their in-place construction costs are very low and their anticipated life-span is quite long. Building systems finished with gypsum-based products typically require minimal routine maintenance and are easily repaired without extensive or costly procedures. If installed and maintained in a proper environment, gypsum-based products will perform acceptably for decades.
In most contemporary green standards, a plan that identifies the expected life span of materials and systems installed in or incorporated into the structure of a building will earn building life service credits. Under normal conditions, gypsum panels and gypsum plaster products have an expected service life exceeding 50 years. Also, gypsum’s inherent fire-resistant properties will protect a building and its many systems from damage in the event of a fire or heat-related incident.
CONSTRUCTION WASTE DIVERSION AND ON-SITE WASTE DISPOSAL
Most green building standards allow credits for using materials that can be recycled using conventional techniques. Clean (as in unpainted or not generated during demolition) gypsum construction waste, depending upon jurisdictional requirements, can be recycled and used to manufacture new gypsum products.
Ground gypsum also can be used as a soil enhancement. Studies have shown that ground gypsum, spread at an even rate over or mixed with the top layer of soil, may be applied at a rate of up to 22 tons per acre on building lots. Machinery specifically designed to pulverize the gypsum to an acceptable size for this application are available to facilitate this process.
Green building standards also allow points for energy conservation and recycling by manufacturers. Newer gypsum plants have been designed for maximum energy efficiency, and several existing plants have been upgraded to improve their energy efficiency. For instance, many gypsum production facilities use co-generated electrical power or heat in their manufacturing processes.
Some manufacturing plants recycle water used in the manufacturing process and are nearly self-sustaining in water use. In addition, several manufacturing plants are certified as meeting green standard requirements for implementing environmental management systems. Again, facility compliance should be examined on a plant-by-plant basis and verified by specific product manufacturers.
Gypsum plants win awards for their green operation. Several gypsum manufacturing facilities in North America have received recognition for their environmentally sound practices from groups as diverse as the Wildlife Habitat Council, and the Mine Safety Health Administration.
So, when faced with a project that requires meeting the provisions of a green building standard in the name of “sustainability,” rest assured that using gypsum products will help contribute to earning the points necessary for satisfying those provisions. W&C