View source for Sheetrock All Purpose Joint Compound

== Description ==
[USG] A registered trademark for a ready-mix limestone-based all-purpose joint compound. Sheetrock All Purpose Joint Compound is used to bridge joins and repair imperfections on drywall and plaster. It is recommended for use with USG Sheetrock Brand Paper Joint Tape for applying drywall filling and finishing coats. It may also be used to hand-apply simple textures on drywall surfaces.<ref>[https://www.usg.com/content/dam/USG_Marketing_Communications/united_states/product_promotional_materials/finished_assets/sheetrock-all-purpose-joint-compound-submittal-J1969.pdf USG(2016) USG Sheetrock Brand All Purpose Joint Compound Submittal Sheet]</ref>

== Personal Risk ==
Health hazard statement: This material may cause cancer by inhalation. It may cause damage to organs (lungs) through prolonged or repeated exposure.

This material is a Category 1A carcinogen (known to have carcinogenic potential for humans). On the basis of evidence from studies in experimental animals, this substance can be presumed to have the potential to be harmful to human health following single exposure (Specific Target Organ Toxicity, repeated exposure, Category 2 – Lungs)

Inhalation of dust may cause respiratory irritation. Prolonged and repeated exposure to airborne respirable crystalline silica can cause silicosis and/or lung cancer.

USG: [https://www.usg.com/content/dam/USG_Marketing_Communications/united_states/sds/usg-sheetrock-all-purpose-joint-compound-ready-mixed-sds-en-61000010001.pdf SDS].

== Environmental Risk ==

== Collection Risk ==
[http://www.conservation-wiki.com/wiki/Oddy_Test_Results:_Case_Construction_Materials#USG Oddy Testing] performed by the Metropolitan Museum of Art (07/05/2018) indicated USG Sheetrock All-Purpose Joint Compound as unsuitable for use with collections.

[http://www.conservation-wiki.com/w/images/2/20/2189_GCMS.pdf Gas Chromatography-Mass Spectrometry] performed on the volatile organic compounds emitted from the material indicated the presence of acetic acid, a known collection hazard (catalyzes corrosion of metals, degradation of organic materials). 

Several other potentially hazardous compounds were also detected aldehydes (can convert to acids with heat or exposure to UV light) and acids (lower pH, corrosive to metals, degrade organic materials)
VOC content: 2g/L

== Working Properties ==
USG Sheetrock All Purpose Joint Compound should be applied in a thin layer over a joint to embed paper tape, with a margin of approximately 1/32 in. of compound. Edges should be feathered.<ref>[https://www.usg.com/content/dam/USG_Marketing_Communications/united_states/product_promotional_materials/finished_assets/sheetrock-gypsum-panels-installation-guide-en-J371.pdf USG(2015) USG Sheetrock Brand All Purpose Joint Compound Installation and Finishing Guide]</ref>
The compound should be let dry and then sanded lightly. A second coat should be applied and feathered 2 inches beyond the margin of the first coat. Once dry, the second coat should be lightly sanded to remove tool marks. A third coat should be applied, again terminating 2 in. beyond the previous coat and feathered. Once dry, the third coat should be sanded.  
Finish fastener heads, corner bead and inside corners as required with at least three coats of joint compound, feathered out onto panel faces and finished to a smooth surface. 

Joint compound should be applied at temperatures of at least 55°F (13°C). Adequate ventilation should be provided to remove excess moisture as the compound dries.

Cleanup: Wash tools with warm, soapy water, and wipe dry to prevent rusting. 

== Exhibit Construction Reviews/Tips/Case Studies ==

== Forms and Sizes ==
The product is available in the following sizes: 1.75 pt, 3.5 qt, 3.5 gal (plastic tubs)

== Resources and Citations ==
* USG: [https://www.usg.com/content/usgcom/en/products/walls/drywall/joint-compound/conventional-weight-joint-compounds/sheetrock-all-purpose-joint-compound.html Sheetrock All-Purpose Joint Compound]
* Jennifer Mikes, contributed information, MWG group, 2020.

[[Category:Materials database]][[Category:MWG]][[Category: Putty/Filler]]