The Gypsum Association (GA, www.gypsum.org) publishes the gypsum industry reference guide GA-236-2016: Joint Treatment Under Extreme Weather Conditions, about the application and drying of gypsum materials and gypsum joint compounds and adhesives in weather conditions. The two-page special recommendation highlights proper procedures during the application and drying of joint compounds and adhesives to ensure compliance with GA-216-2016: Application & Finishing of Gypsum Panel Products. Weather conditions and weather events, such as wet and humid weather, impact the drying times of gypsum joint treatment materials.
Wet and humid weather slow drying times and increase risk of freezing of gypsum materials and gypsum joint compounds and adhesives. Further, changes in humidity can cause movement in wood framing, effecting the application and finishing of gypsum materials and gypsum panel products. GA-236-2016: Joint Treatment Under Extreme Weather Conditions recommends a series of preventive measures, not corrective actions, to compensate for or minimize the effects of wet and humid weather, and to avoid potential problems with gypsum materials and gypsum panel products.
Maintaining recommended environmental conditions before, during, and after the application and finishing of gypsum panel products are all important factors in minimizing the effects of wet and humid weather on gypsum materials and gypsum joint compounds and adhesives. The gypsum industry reference guide GA-236-2016: Joint Treatment Under Extreme Weather Conditions notes the following five preventive measures and best practices for gypsum joint treatment under relative humidity (RH):
- Allow each coat of joint compound to thoroughly dry before the application of subsequent coats.
- Refer to the Joint Compound Drying Time chart for drying rates.
- Do not rely on moisture meters or visual observations to check for joint dryness.
- Select setting-type compounds, when conditions are cold and wet.
- Store joint tape and powder compounds off the ground and in a dry area.
For more information, see GA-236-2016: Joint Treatment Under Extreme Weather Conditions, Joint Compound Drying Time chart and table, showing how temperature and relative humidity (RH) effect drying time for each coat of joint compound at a 1/16-inch (1.6 mm) thickness. In the chart and table, green shaded areas represent the best drying conditions, and red shaded areas represent environmental conditions to avoid. Where poor or slow drying conditions exist, drying times can exceed three days, causing finishing problems.
(Source: Gypsum Association, GA-236-2016: Joint Treatment Under Extreme Weather Conditions)
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