2019
- Acquired Nakan, a global compounding solutions business
- Acquired DaVinci Roofscapes
2018
- Listed as a "Fortune 500" company
- Announced expansions in chlor-alkali, PVC and VCM capacities at facilities in Germany and Louisiana
2017
- Completed 250 million pound ethylene expansion in Lake Charles, Louisiana
- Completed 100 million pound ethylene expansion in Calvert City, Kentucky
2016
- Celebrated 30th anniversary worldwide
- Acquired Axiall Corporation
2015
- Acquired additional interest in Suzhou Huasu Plastics Company
- Named a "Forbes Top 100 Most Trustworthy Companies in America"
2014
- Dedicated Geismar, Louisiana Chlor-Alkali Plant
- Established Westlake Chemical Partners
- Acquired Vinnolit Holdings GmbH
- Announced Lake Charles Petro 1 Ethylene Expansion
- Completed Calvert City Expansions
2013
- Acquired CertainTeed's PVC Pipe, Fittings & Foundations business
- Started-up Geismar, Louisiana Chlor-Alkali Plant
2010
- Acquired 50% ownership of Cypress Pipeline
- Commenced construction of a new chlor-alkali plant in Geismar, Louisiana
