Innovation Challenge Spotlight: Wallboard
The Challenge: Create a building product that is safe, healthy, affordable, effective, and designed to be returned safely to nature or industry after use. This blog, posted weekly leading up the announcement of the Innovation Challenge winners on November 15, spotlights the key issues with conventional building materials and how the ten finalists’ innovations stand out. This week, we focus on wallboard.
The main component of traditional wallboard is gypsum (calcium sulfate). In rare but troubling cases, hydrogen sulfide can outgas from wallboard into homes. Affected homeowners have reported issues including breathing problems, eye irritation, and corroding copper pipes and wires.1 This corrosion can ruin appliances and heating/cooling systems, and it can be dangerous if it corrodes copper pipes used to transport natural gas.2 The Consumer Product Safety Commission advises homeowners who discover their houses contain toxic drywall to remove all the drywall and replace fire safety equipment and many electrical components3—a staggering expense.
Most reports and lawsuits about toxic drywall focus on imported drywall from China. The Consumer Product Safety Commission received nearly 4,000 complaints about imported drywall installed between 2001 and 2008.4 However, while fewer, there are also lawsuits and complaints about similar problems with American wallboard.5
While gypsum is a naturally occurring mineral that companies mine, more recently, people began creating it synthetically from a coal-fired power plant waste product.
Specifically, coal plants emit sulfur dioxide, which causes acid rain.6 When the Environmental Protection Agency started regulating sulfur dioxide emissions, many coal plants installed a kind of sulfur scrubbing technology called Flue Gas Desulfurization (FGD). This process sends a mixture of limestone, water, and air into the gases coal plants emit. These ingredients react with the sulfur dioxide, trapping the sulfur in a new form: calcium sulfate (gypsum).7 The same compounds that once produced acid rain now produce drywall! This is an exciting way to convert a harmful waste into a useful product, and it reduces the need to mine fresh gypsum.
However, there is some concern that low levels of the heavy metals present in coal might appear in synthetic gypsum. Synthetic gypsum drywall has not been proven to damage indoor air quality, but it can introduce toxic chemicals into water when it is landfilled or when it is used as a soil amendment. Drywall is 15% of demolition and construction waste, so this is an important consideration.8
These two important and highly charged controversies make wallboard decisions difficult. There is some risk of sulfide outgassing, which can cause major home damage and possible health effects. Synthetic gypsum wallboard has great environmental benefit in that it is a reclaimed waste product, yet it may also leach heavy metals.
How the finalists stand out
Stormwall Industries presents a drywall substitute called Stormwall to the Challenge. Stormwall is not made from gypsum, so it avoids the above-mentioned tradeoffs and controversies altogether. It is a composite wood product painted with a VOC-free, GREENGUARD-certified paint. While a common problem with composite wood products is binder-related formaldehyde emissions, Stormwall meets European formaldehyde standards (<8mg/100g).9 It is accredited with the following:
- GREENGUARD Gold
- Green Seal
- International Building Codes (IBC & IRC)
- LEED credits MR 4, 4.4, 5 & 7.
1 Consumer Product Safety Commission. (2009). Executive Summary of November 23, 2009 Release. Retrieved from http://www.cpsc.gov//PageFiles/114700/nov2009execsum.pdf
2 Virginia Department of Health: Division of Environmental Epidemiology. (2010). Frequently Asked Questions about Drywall Imported from China. Retrieved from http://www.vdh.virginia.gov/epidemiology/DEE/PublicHealthToxicology/documents/pdf/chinese%20drywall%20FAQ%20final.pdf
3 Consumer Product Safety Commission. (Date Unknown). What Should I Do if my Home Has Problem Drywall? Retrieved from http://www.cpsc.gov/Safety-Education/Safety-Education-Centers/Drywall/Topics/What-should-I-do-if-my-home-has-problem-drywall/
4 Centers for Disease Control and Prevention. (2011). Imported Drywall and Your Home. Retrieved from http://www.cdc.gov/nceh/drywall/imported_drywall_and_your_home.html
5 Sapien, J. & A. Kessler. (2010). American-Made Drywall Emerges as Potential Danger. Retrieved from http://www.propublica.org/article/american-made-drywall-emerges-as-potential-danger
6 Unknown Author (2010). Synthetic Gypsum. Environmental Building News, 19(8). Retrieved from http://www.buildinggreen.com/auth/article.cfm/2010/7/30/Synthetic-?CFID=997925&CFTOKEN=67823645
7 Wendt, A. (2009). Drywall Problems Escalate. Environmental Building News. Retrieved from http://www.buildinggreen.com/auth/article.cfm/2009/7/21/Drywall-?CFID=997925&CFTOKEN=67823645
8 Solomon, M. (2012). Gypsum Board: Are Our Walls Leaching Toxins? GreenSpec. Retrieved from http://greenspec.buildinggreen.com/blogs/gypsum-board-are-our-walls-leaching-toxins
9 Unknown Author. (2008). Update on Formaldehyde Release from Wood-Based Panels. Retrieved from http://www.chimarhellas.com/wp-content/uploads/2008/07/formaldehyde_2008.pdf