WESTLAKE CORP

General

We are a vertically integrated global manufacturer and marketer of performance and essential materials and housing and infrastructure products that enhance the lives of people every day. Our products include some of the most widely used materials in the world, which are fundamental to many diverse consumer and industrial markets, including residential construction, flexible and rigid packaging, automotive products, healthcare products, water treatment, wind turbines, coatings as well as other durable and non-durable goods. We operate in two principal operating segments, Performance and Essential Materials and Housing and Infrastructure Products. Performance and Essential Materials includes Westlake North American Vinyls, Westlake North American Chlor-alkali & Derivatives, Westlake European & Asian Chlorovinyls, Westlake Olefins, Westlake Polyethylene and Westlake Epoxy. Housing and Infrastructure Products includes Westlake Royal Building Products, Westlake Pipe & Fittings, Westlake Global Compounds and Westlake Dimex. We are highly integrated along our materials chain with significant downstream integration from ethylene and chlor-alkali (chlorine and caustic soda) into vinyls, polyethylene and styrene monomer. We also have substantial downstream integration from polyvinyl chloride ("PVC") into our building products, PVC pipes and fittings and PVC compounds in our Housing and Infrastructure Products segment.

We began operations in 1986. Since 1986, we have grown rapidly into an integrated global producer of chemicals and building products. We achieved this growth by acquiring existing plants or constructing new plants and completing numerous capacity or production line expansions. We regularly consider acquisitions and other internal and external growth opportunities that would be consistent with, or complementary to, our overall business strategy.

In 2014, we formed Westlake Chemical Partners LP ("Westlake Partners") to operate, acquire and develop ethylene production facilities and related assets. Also in 2014, Westlake Partners completed an initial public offering of common units (the "Westlake Partners IPO"). As of February 18, 2025, Westlake Partners' assets consisted of a 22.8% limited partner interest in Westlake Chemical OpCo LP ("OpCo"), as well as the general partner interest in OpCo. Prior to the Westlake Partners IPO, OpCo's assets were wholly-owned by us. OpCo's assets include two ethylene production facilities at our olefins facility in Lake Charles, one ethylene production facility at our Calvert City site and a 200-mile common carrier ethylene pipeline that runs from Mont Belvieu, Texas to the Longview, Texas site, which includes our Longview polyethylene production facility. We retain a 77.2% limited partner interest in OpCo, a 40.1% limited partner interest in Westlake Partners (consisting of 14,122,230 common units), a general partner interest in Westlake Partners and incentive distribution rights. The operations of Westlake Partners are consolidated in our financial statements. We are party to certain agreements with Westlake Partners and OpCo whereby, among other things, OpCo sells us 95% of the ethylene it produces on a cost-plus basis that is expected to generate a fixed margin per pound of $0.10. We use this ethylene in the production processes of our Performance and Essential Materials segment. For more information, see "—Performance and Essential Materials Business" below.

On November 12, 2019, we completed the acquisition of an additional 34.8% of the membership interests in LACC, LLC ("LACC") from Lotte Chemical USA Corporation, a subsidiary of Lotte Chemical Corporation ("Lotte"), for approximately $817 million (the "Transaction"). Prior to the Transaction, we owned approximately 12% of the membership interests in LACC. On March 15, 2022, the Company completed the acquisition of an additional 3.2% membership interest in LACC from Lotte for approximately $89 million. As of December 31, 2024, we owned an aggregate 50% membership interest in LACC. The LACC ethylene plant has 2.2 billion pounds per year of ethylene production capacity and is adjacent to our chlor-alkali facility in Lake Charles. We receive our proportionate share of LACC's ethylene production on a cash-cost basis, which is expected to benefit our integrated downstream operations.

On June 20, 2021, we, through one of our wholly-owned subsidiaries, entered into an Equity Purchase Agreement (the "Boral Purchase Agreement") by and among Boral Building Products Inc., a Michigan corporation, Boral Stone Products LLC, a Delaware limited liability company, Boral Lifetile Inc., a California corporation, Boral Windows LLC, a Utah limited liability company, Boral Industries Inc., a California corporation ("Boral Industries"), and, solely for the limited purposes set forth therein, we and Boral Limited, an Australian corporation ("Boral"). Pursuant to the terms of the Boral Purchase Agreement, we agreed to acquire from Boral Industries all of the issued and outstanding equity interests of certain subsidiaries of Boral Industries engaged in Boral's North American building products businesses in roofing, siding, trim and shutters, decorative stone and windows (the "Boral Target Companies"). On October 1, 2021, we completed the acquisition of the Boral Target Companies. The total consideration was $2,140 million in an all-cash transaction. The assets acquired and liabilities assumed and the results of operations of this business are included in the Housing and Infrastructure Products segment.

On August 19, 2021, we completed the acquisition of, and acquired all of the equity interests in LASCO Fittings, Inc. ("LASCO"), a manufacturer of injected-molded PVC fittings that serve the plumbing, pool and spa, industrial, irrigation and retail markets in the United States from Aalberts U.S. Holding Corp. and Aalberts N.V. (the "LASCO Acquisition"). The total consideration was $277 million. The assets acquired and liabilities assumed and the results of operations of LASCO are included in the Housing and Infrastructure Products segment.

On September 10, 2021, we completed the acquisition of, and acquired all of the equity interests in, DX Acquisition Corp. ("Dimex"), a producer of various consumer products made from post-industrial-recycled polyvinyl chloride, polyethylene and thermoplastic elastomer materials, including, landscape edging; industrial, home and office matting; marine dock edging; and masonry joint controls The total consideration was $172 million. The assets acquired and liabilities assumed and the results of operations of Dimex are included in the Housing and Infrastructure Products segment.

On February 1, 2022, we completed the acquisition of the global epoxy business of Hexion Inc. ("Westlake Epoxy") for a total consideration of $1,207 million. The assets acquired and liabilities assumed and the results of operations of Westlake Epoxy are included in the Performance and Essential Materials segment. During the fourth quarter of 2023, the Westlake Epoxy business's sales volumes and prices, specifically base epoxy resins in Europe, continued to deteriorate. These lower sales volumes and prices were primarily driven by record exports at lower prices of bisphenol-A, epichlorohydrin and base epoxy resins (constituting the epoxy value chain) out of Asia into Europe and North America during the time when demand in the European market was contracting. In addition, Westlake Epoxy operations in Europe experienced sustained high energy and power costs. These factors negatively impacted Westlake Epoxy financial results during 2023. Based on these developments, along with management's outlook for the Westlake Epoxy business over the foreseeable future, we determined, in the fourth quarter of 2023, that the carrying amount of long-lived assets of our base epoxy resin business in the Netherlands and all of the goodwill of the Westlake Epoxy business will not be recoverable. As a result of this assessment, a goodwill impairment charge of $128 million and a non-cash long-lived asset impairment charge related to Epoxy Netherlands base epoxy resin business assets of $347 million were recognized in the fourth quarter of 2023. In July 2024, the Company approved a plan to temporarily cease operations ("mothball") of the allyl chloride (AC) and epichlorohydrin (ECH) units at the Company's site in Pernis, the Netherlands (collectively, the "Units"). The Company continues to operate the liquid epoxy resin (LER) and bisphenol A (BPA) units at the Pernis facility. The Units are expected to temporarily cease operations in 2025.

As a global manufacturer of products in the performance and essential materials and housing and infrastructure products businesses, we continue to build on our core strengths in delivering high-value, essential products for our customers and endeavor to produce and deliver these products in increasingly-sustainable ways. To further these objectives, we endeavor to reduce the environmental footprint of our operations and enhance the circularity in more of our products, including continuing to focus on recycling opportunities within our businesses, reducing waste at our facilities, incorporating more recycled content into our products, and seeking to incorporate renewable and bio-based materials. We established a target 20% reduction in our Scope 1 and Scope 2 CO2 equivalent ("CO2e") emissions intensity per ton of production by 2030 from a 2016 baseline (CO2e Emissions Intensity Goal). For the purposes of tracking performance results over time for our CO2e Emissions Intensity Goal, we use a combination of standard and site-specific emission factors (EPA or industrial). These factors, when combined with operational data such as natural gas usage, allow us to calculate an equivalent carbon dioxide emissions total for our operations. These Scope 1 emissions, when combined with Scope 2 emission information from our utility suppliers, allow same-basis comparisons to the base year. As of December 31, 2023, we had achieved a total reduction of approximately 16% in Scope 1 and Scope 2 GHG emissions intensity from our 2016 intensity baseline. Relatively higher emissions intensity in 2023 as compared to the prior year primarily occurred due to lower production rates. Although our progress against our CO2e emissions Intensity Goal is and will continue to be measured according to our calculation methodology used to set the intensity goal in order to maintain comparability, we have also reported Scope 1 and Scope 2 emissions starting January 1, 2023, according to the methodology set forth in the Greenhouse Gas Protocol Corporate Accounting and Reporting Standard.

Performance and Essential Materials Business

Products

Principal products in our integrated Performance and Essential Materials segment include ethylene, polyethylene, styrene, chlor-alkali (chlorine and caustic soda), chlorinated derivative products, ethylene dichloride ("EDC"), vinyl chloride monomer ("VCM") and PVC. We manage our integrated vinyls production chain to optimize product margins and capacity utilization.

We manufacture ethylene through three of the OpCo plants and our portion of LACC's production capacity located in Lake Charles and Calvert City. Chlor-alkali materials are produced at our three plants located in Lake Charles, two plants located in Germany and one plant each located in Calvert City, Plaquemine, Geismar, Natrium, Longview and Beauharnois. Our VCM is produced at our two plants in Lake Charles, two plants located in Germany and one plant each at Calvert City, Plaquemine and Geismar. Our PVC is produced at our four plants located in Germany and one plant each at Calvert City, Plaquemine, Geismar and Aberdeen. Polyethylene and associated products are produced at our two polyethylene plants in Lake Charles and three polyethylene plants and a specialty polyethylene wax plant at our Longview site. Our chlorinated derivative products are primarily produced at our plants in Lake Charles and Natrium. Styrene monomer is produced at our plant located in our Lake Charles facility. Epoxy Specialty Resins are produced at two plants located in Germany, two plants in the United States, one plant in Spain and one plant in South Korea. Base Epoxy Resins and Intermediaries are produced at our plants in Pernis, the Netherlands and Deer Park, United States. Our other Asian manufacturing facilities are located near Shanghai, in China, and in Kaohsiung, Taiwan, through our 95%- and 60%-owned joint ventures, respectively, where we produce chlor-alkali, PVC and associated products. As of February 18, 2025, we (directly and through OpCo, our investment in LACC, and our 95%- and 60%-owned joint ventures in China and Taiwan, respectively) had approximately 43.3 billion pounds per year of aggregate production capacity at numerous manufacturing sites in North America, Europe and Asia in our Performance and Essential Materials segment.

The following table illustrates our Performance and Essential Materials segment production capacities at February 18, 2025 by principal product and the end uses of these products:

(1) EDC, a VCM intermediate product, is not included in the table.

(2) Includes capacity related to our 95%- and 60%-owned Asian joint ventures.

(3) Includes production capacity in Lake Charles and Calvert City owned by OpCo and our portion of LACC's production capacity in Lake Charles. For additional information on OpCo, see "Ethylene" below.

(4) Except as noted in notes (5) and (6) below, we own each of these facilities.

(5) We lease the land on which our Gendorf, Burghausen, Knapsack, Cologne and Esslingen, Germany facilities, Pernis, Rotterdam, The Netherlands facility, Longview and Deer Park, Texas facilities and Argo, Illinois facility are located. We also lease the Esslingen, Germany building.

(6) We lease a portion of the land on which our Aberdeen and Calvert City facilities are located.

(7) In July 2024, the Company approved a plan to temporarily cease operations of the AC and ECH units at the Pernis facility during 2025. Annual capacity of 155 million pounds associated with ECH production at the Pernis facility is included in this table.

Ethylene. Ethylene is the world's most widely used petrochemical in terms of volume. It is the key building block used to produce a large number of higher value-added chemicals including polyethylene, EDC, VCM and styrene. OpCo has the capacity to produce approximately 3.0 billion pounds of ethylene per year at our Lake Charles site, and we have the capability to consume all of OpCo's production that we purchase at Lake Charles to produce EDC, VCM, polyethylene and styrene monomer. In addition, we (through OpCo) produce ethylene co-products including chemical grade propylene, crude butadiene, pyrolysis gasoline and hydrogen. We (through OpCo) sell our entire output of these co-products to external customers. The ethylene from OpCo's facility in Calvert City and LACC is utilized to produce VCM at our facilities. We obtain the remainder of the ethylene we need for our business from third party purchases. The use of ethane feedstock by our ethylene plants enables us to enhance our low-cost materials chain integration.

Chlorine and Caustic Soda. We are the second-largest chlor-alkali producer in the world. We have the capacity to produce approximately 7.4 billion pounds of chlorine and 8.1 billion pounds of caustic soda. We combine salt and electricity to produce chlorine and caustic soda, commonly referred to as chlor-alkali, at our Lake Charles, Plaquemine, Natrium, Calvert City, Geismar, Beauharnois, Longview (WA), Gendorf, Knapsack and Kaohsiung facilities. Our Lake Charles, Plaquemine and Natrium cogeneration assets have the capacity to generate approximately 845, 240 and 100 megawatts of electricity, respectively, per year. We use our chlorine production in our VCM and chlorinated derivative products plants. We currently have the capacity to supply all of our chlorine requirements internally. Any remaining chlorine is sold into the merchant chlorine market. Our caustic soda is sold to external customers who use it for, among other things, the production of pulp and paper, organic and inorganic chemicals and alumina.

VCM. VCM is used to produce PVC, solvents and PVC-related products. We use ethylene and chlorine to produce EDC, which is used in turn, to produce VCM. We have the capacity to produce approximately 6.3 billion pounds and 1.6 billion pounds of VCM per year at our North American and European facilities, respectively. The majority of our VCM is used internally in our PVC operations. VCM and EDC not used internally are sold externally.

PVC. PVC, the world's third most widely used plastic, is an attractive alternative to traditional materials such as glass, metal, wood, concrete and other plastic materials because of its versatility, durability and cost-competitiveness. PVC is produced from VCM, which is, in turn, made from chlorine and ethylene.

We are the second-largest PVC producer in the world. With the completion of our previously announced expansion projects at our Geismar and Burghausen plants in 2019, we have the capacity to produce approximately 6.8 billion pounds and 1.0 billion pounds of commodity and specialty PVC per year, respectively, at our various facilities globally. We use some of our PVC internally in the production of our building products, PVC pipes and fittings and PVC compounds in the Housing and Infrastructure Products segment. The remainder of our PVC is sold to downstream fabricators and the international markets.

Polyethylene. Polyethylene, the world's most widely consumed polymer, is used in the manufacture of a wide variety of film, coatings and molded product applications primarily used in packaging. Polyethylene is generally classified as either LDPE, LLDPE or high-density polyethylene ("HDPE"). The density correlates to the relative stiffness of the end-use products. The difference between LDPE and LLDPE is molecular, and products produced from LLDPE, in general, have higher strength properties than products produced from LDPE. LDPE exhibits better clarity and other physical properties and is used in end products such as bread bags, food wraps, milk carton coatings and food packaging. LLDPE is used for higher film strength applications such as stretch film and heavy-duty sacks. HDPE is used to manufacture products such as grocery, merchandise and trash bags, rigid plastic containers, plastic closures and pipe.

We are a leading producer of LDPE by capacity in North America and predominantly use the autoclave technology (versus tubular technology), which is capable of producing higher-margin specialty polyethylene products. In 2024, our annual capacity of approximately 1.5 billion pounds of LDPE was available in numerous formulations to meet the needs of our diverse customer base. We also have the capacity to produce approximately 1.1 billion pounds of LLDPE per year in various formulations. We produce LDPE and LLDPE at both the Lake Charles and Longview (TX) facilities. Our Lake Charles and Longview facilities also have the capability to produce HDPE. We sell polyethylene to external customers as a final product in pellet form.

Chlorinated Derivative Materials. Our chlorinated derivative products include ethyl chloride, perchloroethylene, trichloroethylene, tri-ethane® solvents, VersaTRANS® solvents, calcium hypochlorite, hydrochloric acid ("HCL") and pelletized caustic soda. We have the capacity to produce approximately 2.2 billion pounds of chlorinated derivative products per year, primarily at our Lake Charles, Natrium, Beauharnois and Longview (WA) facilities. The majority of our chlorinated derivative products are sold to external customers who use these products for, among other things, refrigerants, water treatment applications, chemicals and pharmaceutical production, food processing, steel pickling, solvent and cleaning chemicals and natural gas and oil production.

Styrene. Styrene is used to produce derivatives such as polystyrene, acrylonitrile butadiene styrene, unsaturated polyester and synthetic rubber. These derivatives are used in a number of applications including consumer disposables, food packaging, housewares, paints and coatings, building materials, tires and toys. We produce styrene at our Lake Charles plant, where we have the capacity to produce approximately 570 million pounds of styrene per year, all of which is sold to external customers.

Epoxy Specialty Resins. With the acquisition of the Westlake Epoxy business, Westlake is now one of the leading producers of epoxy specialty resins, modifiers and curing agents in Europe, the United States and Asia with a global reach to our end markets. Epoxy resins are the fundamental component of many types of materials and are often used in the automotive, construction, wind energy, aerospace and electronics industries due to their superior adhesion, strength and durability. Epoxy specialty resins are used for a variety of high-end coating applications that require superior adhesion, corrosion resistance and durability of epoxy such as protective coatings that are used for construction, flooring and transportation, among others. Epoxy-based surface coatings are among the most widely used industrial coatings due to their long service life and broad application functionality combined with overall economic efficiency. Our epoxy specialty resins are also used for electrical applications such as generators, bushings, transformers and medium and high voltage switch gear components. In composites, our specialty epoxy products are used either as replacements for traditional materials such as metal, wood and ceramics, or in applications where traditional materials do not meet demanding engineering specifications. We are also one of the leading producers of resins that are used in fiber reinforced composites. Composites are used in a wide variety of applications ranging from wind energy, automotive, aerospace, construction and industrial applications. We produce epoxy specialty resins at our Duisburg and Esslingen plants in Germany, Barbastro plant in Spain, Onsan plant in South Korea, and Lakeland and Argo plants in the United States. We have the total capacity to produce approximately 580 million pounds of epoxy specialty resins per year, all of which is sold to external customers.

Base Epoxy Resins and Intermediaries (BERI). We are a leading supplier of Liquid and Solid Epoxy Resin. These base epoxies are used in a wide variety of industrial coatings applications. In addition, we are a major producer of bisphenol-A ("BPA"), a key precursor in the downstream manufacturing of basic epoxy resins and specialty resins. We internally consume the majority of our BPA, which ensures consistent supply of our required intermediate materials. We produce base epoxies and intermediaries at our Deer Park, United States and Pernis, the Netherlands plants, where we have the capacity to produce approximately 1,280 million pounds per year.

Product and Application Development. Our product and application development activities are geared towards developing and enhancing products, processes and applications. Facilities where we perform such activities are located in the United States, Germany, China and the Netherlands.

Feedstocks

We are highly integrated along our materials production chain. We (through OpCo) produce most of the ethylene required to produce our polyethylene and styrene. Ethylene can be produced from either petroleum liquid feedstocks, such as naphtha, condensates and gas oils, or from natural gas liquid feedstocks, such as ethane, propane and butane. Both of OpCo's Lake Charles ethylene plants use ethane as the primary feedstock. Pursuant to a feedstock supply agreement between us and OpCo, OpCo receives ethane feedstock at our Lake Charles site through several pipelines from a variety of suppliers in Texas and Louisiana. We own a 50% interest in a 104-mile natural gas liquids pipeline from Mont Belvieu to our Lake Charles site. OpCo owns a 200-mile ethylene pipeline that runs from Mont Belvieu to our Longview (TX) site. Additionally, through OpCo, we produce most of the ethylene required at our Calvert City facility utilizing ethane feedstock. The LACC ethylene facility is located adjacent to our chlor-alkali facility in Lake Charles and has an ethylene production capacity of 2.2 billion pounds per year. During the third quarter of 2019, the LACC ethylene plant began its commercial operations. At December 31, 2024, we, through one of our subsidiaries, owned 50% of the membership interests in LACC. We receive our proportionate share in ethylene production on a cash-cost basis and primarily use it to produce VCM. In Germany, we have access to, and partially own, an ethylene pipeline.

We acquire butene and hexene to manufacture polyethylene and benzene to manufacture styrene. We receive butene and hexene at the Lake Charles site and hexene at the Longview (TX) site via rail car from several suppliers. We receive benzene via barges, ships and pipeline pursuant to short-term arrangements. We purchase butene and hexene pursuant to multi-year contracts.

The salt requirements for several of our larger chlor-alkali plants are supplied internally from salt domes we either own or lease and the salt is transported by pipelines we own. We purchase the salt required for our other chlor-alkali plants pursuant to long-term contracts. Electricity and steam for one of our Lake Charles facilities and our Plaquemine facility are produced by on-site cogeneration units. A portion of our Natrium facility's electricity requirements is produced by our on-site generation unit, and the remainder is purchased. We purchase electricity for our remaining facilities under long-term contracts. We purchase VCM for our Asian PVC plant on a contract and spot basis.

The raw materials that we primarily use to manufacture our epoxy products include chlorine, caustic soda, phenol and acetone, all of which are available from more than one source. Prices for our main feedstocks are generally driven by the underlying petrochemical benchmark prices and energy costs, which are subject to price fluctuations.

Sustainability

We continued our efforts to deliver high-value products in increasingly sustainable ways in 2024. For instance, having introduced lower-carbon caustic soda and PVC products since early 2021. In October 2022, we expanded our GreenVin® bio-attributed PVC, which is produced in Germany with renewable power (under European Guarantees of Origin) and renewable ethylene. The renewable ethylene is derived from second-generation waste biomass. GreenVin® bio-attributed PVC is both International Sustainability & Carbon Certification PLUS and REDcert2 certified, using the mass balance approach. Bio-attributed GreenVin® PVC is approximately 90% less carbon intensive compared with conventionally produced Westlake PVC in Germany, based on a cradle-to-gate product carbon footprint study by Sustainable AG, tested by TÜV Rheinland, in accordance with the ISO 14067 standard, taking biogenic CO2 fixations into account.

Another example of our efforts to improve the sustainability of our products is our incorporation of higher volumes of recycled materials in our polyethylene resin. Our customers use our one-pellet polyethylene compound, PIVOTAL®, a product line that contains a blend of post-consumer-recycled (PCR) and virgin polyethylene resins and has obtained GreenCircle certification, to achieve PCR content in their products ranging from 25% to 70%.

In Europe, Westlake Epoxy reformulated certain curing agents to exclude "substances of very high concern" (SVHC) and "carcinogenic, mutagenic or toxic for reproduction" (CMR)-labelled substances in 2023. They are now offered under the new Azures™ name.

Marketing, Sales and Distribution

We have a dedicated sales force for our business, organized by product line and region that sells our products directly to our customers. In addition, we rely on distributors to market products to smaller customers. Our polyethylene customers are some of the nation's largest producers of film and flexible packaging. We and OpCo sell ethylene and ethylene co-products to external customers. OpCo's primary ethylene co-products are chemical grade propylene, crude butadiene, pyrolysis gasoline and hydrogen. We have storage agreements and exchange agreements that provide us and OpCo with access to customers who are not directly connected to the pipeline system that we own. OpCo ships crude butadiene and pyrolysis gasoline by rail or truck. Additionally, we transport our polyethylene and styrene by rail or truck. Further, styrene can be transported by barge or ship.

We use some of our PVC internally in the production of our building products, pipes and fittings and PVC compounds in the Housing and Infrastructure Products segment. The remainder of our PVC is sold to downstream fabricators and the international markets. We have the capacity to use a majority of our chlorine internally to produce VCM and EDC, most of which, in turn, is used to produce PVC. We also use our chlorine internally to produce chlorinated derivative products. We sell the remainder of our chlorine and substantially all of our caustic soda production to external customers. The majority of our products are shipped from production facilities directly to the customer via pipeline, truck, rail, barge and/or ship. The remaining products are shipped from production facilities to third party chemical terminals and warehouses until being sold to customers.

No single customer accounted for 10% or more of net sales for the Performance and Essential Materials segment in 2024.

Competition

The markets in which our Performance and Essential Materials businesses operate are highly competitive. Competition in the materials market is based primarily on price and to a lesser extent, on product availability, product quality and consistency, product performance and customer service. We sell our commodities products in global markets, and the prices at which we sell certain of our products are affected by production and exports from other countries. As a result, our competitive position is affected by trade regulations, international fair trade laws, policies and disputes, trade barriers, tariffs, duties or other taxes.

Our competitors in the ethylene, polyethylene and styrene markets are some of the world's largest chemical companies, including Chevron Phillips Chemical Company, Dow Inc., ExxonMobil Chemical Company, Formosa Plastics Corporation, LyondellBasell Industries, N.V., NOVA Chemicals Corporation and Sasol Limited. We compete in the chlor-alkali and PVC markets with other producers including Formosa Plastics Corporation, INOVYN ChlorVinyls Limited, KEM ONE Group SAS, Olin Corporation, Orbia Advance Corporation, Occidental Chemical Corporation, Shintech, Inc. and VYNOVA Group. Our competitors in the epoxy value chain include Olin Corporation, Nan Ya Plastics Corporation, the Spolchemie Group, LEUNA-Harze GmbH, Aditya Birla Chemicals (Thailand) Ltd., Huntsman Corporation, Swancor Holding Company Limited, Ningbo Bohui Chemical Technology Co., Ltd., Techstorm Advanced Material Co., Ltd., Shanghai Kangda Chemical New Material Group Co., Ltd., Evonik Industries AG, Allnex Management GmbH, Kukdo Chemical Co., Ltd., Kumhu Asiana Group and Chang Chun Plastics Co., Ltd.

Housing and Infrastructure Products Business

Our Brands and Products

We manufacture and sell housing and infrastructure products including residential PVC siding; PVC trim and mouldings; architectural stone veneer; windows; PVC decking; PVC films for various inflatables, wallcovering, tape and roofing applications; polymer composite and cement roof tiles; PVC pipe and fittings for various water, sewer, electrical and industrial applications; PVC compounds used in various housing, medical and automobile products; and a variety of consumer and commercial products such as landscape edging; industrial, home and office matting; marine dock edging; and masonry joint controls.

Our housing and infrastructure products consist of several product groups including: (i) exterior and interior building products, which includes siding, trim and mouldings, stone, roofing, windows and outdoor living products; (ii) PVC pipe, specialty PVC pipe and fittings; and (iii) PVC compounds. Many of our products are made from PVC, including products for water and sewer systems and home and light commercial applications for siding, trim and mouldings, outdoor living products, windows and PVC compounds.

Siding. Our siding products include insulated siding and vinyl siding and accessory products. Additionally, we offer premium siding products such as Celect®Cellular Composite Siding and, TruExterior® Siding. Our siding business is also a leader in non-wood shutters and siding accessories along with an array of specialty tools to aid installation. Our brands include Royal® Siding, Portsmouth® Shake and Shingle, Foundry® Specialty Siding, TruExterior®Siding&Trim, Celect® Cellular Exteriors, Mid-America® Exteriors, Tapco Tools®, and many more.

Trim and Mouldings. We offer a wide variety of trim and moulding products, including exterior and interior products for homes, multi-family and light commercial structures that are used as substitute for wood and wood composite offerings. Our brands include Royal Trim and Mouldings, TruExterior Siding&Trim, and, Kleer Lumber®, among others.

Stone. We are a leader in the masonry stone veneer category, with both mortar applied products and mechanically fastened products that are used as a substitute for stone on exterior walls and accents as well as in interior applications such as fireplaces, kitchens and bathrooms. Our stone brands include Cultured Stone®, Eldorado Stone®, Versetta Stone®, StoneCraft Industries® and Dutch Quality Stone®, among others.

Roofing. Our DaVinci® Roofscapes is a premium composite roofing. Additional product offerings include concrete and clay roof tiles and stone coated steel roofing. Our other major roofing name brands include NewPoint®, Concrete Roof Tile, US Tile®Clay Roofing Products, Unified Steel®, and Stone Coated Roofing among others.

Windows. We are a regional fabricator of vinyl windows in the South and Southeast markets of the United States. Our brands include Legacy Collection™, the Krestmark® Collection, and the Magnolia Collection™.

Outdoor Living Products. Our outdoor living products include Zuri® Premium Decking and Kindred Outdoor kitchens and fire bowls.

PVC Pipe. We manufacture and sell pipe ranging from ½ inch to 36 inches in diameter, in gasketed, solvent welded, and restrained joint configurations. Our pipe products are used in residential water and sewer applications; municipal potable water and sewer infrastructure; plumbing and industrial applications, including drain, waste & vent ("DWV"); electrical duct and conduit; turf irrigation, water well and other major water transport market segments. We manufacture and market pipe for water, sewer, irrigation and conduit pipe products under the Westlake Pipe & Fittings brand name.

Specialty PVC Pipe. Our specialty PVC pipe includes the Certa-Lok® pipe and Certa-Lok CLICTM joining systems, which provide restrained joints with rapid assembly, designed for use in potable water, sewer, fire protection, agriculture, well-casing, electrical conduit and other piping system applications in the residential and various infrastructure markets. Other specialty products include a system for high rise DWV installations that incorporates low smoke and flame properties. Our molecularly-oriented PVC ("PVCO") pipe, AquaMax™, is produced with less PVC than conventional pipe improving our environmental footprint while delivering higher performance. We also manufacture and market specialty pipe under the Certa-Set®, Certa-Flo®, Certa-Com®, Yelomine®, Fluid-Tite®, Kwik-Set® and Sure-Fit® brand names, among others.

Fittings. Our fittings products include a range of injection molded and custom fabricated fittings including: injection mold DWV fittings for residential, low-rise and high-rise commercial installations; molded gasketed and solvent weld sewer fittings up to 12 inches, molded gasketed municipal pressure fittings and molded fittings for the pool, spa, industrial markets and electrical assemblies; and fabricated custom fittings up to 36 inches for municipal and plumbing installations. We manufacture and market specialty fittings under the Westlake Pipe & Fittings brand name.

PVC Compounds. PVC compounds are custom blended formulations made by combining PVC resin with functional additives. They offer specific end-use properties based on customer-determined specifications and are used to produce rigid and flexible PVC applications. Our compounds are processed via extrusion, injection molding, blow molding calendering. Our primary markets are building materials (housing), pipe and fittings, industrial materials, automotive, healthcare, telecommunications and consumer goods. Flexible PVC compounds are used for, but not limited to, the following applications: wire and cable, flooring, roofing, wall coverings, window and door trims, gaskets, industrial applications, automotive interior and exterior trims, footwear and medical applications. Rigid extrusion PVC compounds are commonly used for pipe, window and door profiles, fencing, decking, railing, siding and trim. Injection molding and blow molding PVC compounds are commonly used for pipe fittings, electrical components, industrial applications and packaging for consumer goods. We manufacture and market custom PVC compounds under the Westlake Global Compounds and Nakan brand names.

Recycled Products. Westlake Dimex is aproducer of post-industrial-recycled PVC, PE and thermoplastic elastomer (TPE) compounds in addition to various consumer and professional products made from recycled PVC, PE and TPE materials. These products include landscape edging; industrial, home and office matting; marine dock edging; and masonry control joints.

Raw Materials and Suppliers

Our North American PVC facilities within the Performance and Essential Materials segment supply most of the PVC required by building products for our housing exteriors and PVC pipes and fittings plants. Our raw materials for stone, roofing and accessories, windows, shutters, and specialty tool products are externally purchased. PVC required for the PVC compounds plants is either internally sourced from our North American and Asian facilities within the Performance and Essential Materials segment or externally purchased based on the location of the plants. The remaining raw materials required, including pigments, fillers, stabilizers, and other ingredients, are purchased under short-term contracts, long-term contracts and in the spot market based on prevailing market prices.

Manufacturing

We operate 58 manufacturing locations primarily in the United States and Canada where we produce siding, trim and mouldings, stone, roofing, windows, outdoor living products, PVC pipes, specialty PVC pipes and fittings. In addition, we have 12 manufacturing locations across the world where we produce PVC compounds, including locations in North America, Europe and Asia. The following table illustrates the properties owned and leased by the Housing and Infrastructure Products business:

Marketing, Sales and Distribution

We sell a majority of our siding, trim and mouldings, stone, roofing, windows and outdoor living products, PVC pipe, specialty PVC pipe and fittings through a combination of our internal sales force and some manufacturer's representatives. In North America, we operate 40 leased and 7 owned distribution centers, storage and warehouses that service and supply these products to local customers, contractors and distributors. We also engage in advertising programs primarily directed at trade professionals and homeowners that are intended to develop awareness and interest in our products. In addition, we display our products at trade shows. Additionally, our 12 PVC Compounds manufacturing facilities across the world sell through a combination of our internal sales force and distributors.

No single customer accounted for 10% or more of net sales for the Housing and Infrastructure Products segment in 2024.

Sustainability

We endeavor to continue to focus on manufacturing products in a more sustainable way and developing products with improved sustainable features. For instance, since 2023, we have been planning to expand production of Westlake molecular-oriented polyvinyl chloride ("PVCO") pipe from Canada to the U.S., which offers both enhanced water flow and a lower-carbon footprint due to its lighter weight compared to traditional Westlake PVC pipe. Westlake PVCO pipe provides an approximately 10% increase in internal flow area compared with pipes with the same outside diameter, and approximately 40% less PVC pipe weight compared to traditional Westlake PVC pipe used for distribution of potable water, sewer and other systems. Less material per unit length provides secondary benefits for shipping the product.

We also enhanced circularity of more of our products as discussed in our 2023 Sustainability Report, which is available at our website at www.westlake.com. Following our acquisition of Westlake Dimex, we started to utilize increasing amounts of in-house generated PVC plastic regrind purchased from other Westlake businesses, in addition to purchasing post-industrial recycled materials from third parties. In 2023, Westlake Dimex doubled the tonnage of in-house post-industrial waste received from within Westlake businesses and customers. In 2023, two of our stone veneer products produced at our two facilities incorporated approximately 45% (Versetta Stone) to 55% (Cultured Stone) recycled content. Unless specifically stated herein, documents and information on our website, including our 2023 Sustainability Report, are not incorporated by reference in this Form 10-K.

Competition

The markets in which our housing and infrastructure businesses operate are highly competitive. Competition in the housing and infrastructure products market is based on product quality, product innovation, customer service, product consistency, on-time delivery and price. We compete in the housing and infrastructure products market with other producers and fabricators including Associated Materials LLC., CertainTeed Corporation, Cornerstone Building Brands, Inc., Diamond Plastics Corporation, IPEX Inc., JM Eagle Inc., Trex Company, Inc. and The Azek Company and with producers of PVC compounds including GEON Performance Solutions and Teknor Apex Company, Inc.

Seasonality

Though we generally experience demand for our products throughout the year, our sales, particularly of housing products have historically experienced some seasonality. We have typically experienced moderately higher levels of sales of our residential products in the first half of the year due to inventory restocking and improved weather for construction. Our sales are affected by the individual decisions of distributors and dealers on the levels of inventory they carry, their views on product demand, their financial condition and the manner in which they choose to manage inventory risk. Our sales are also generally impacted by the number of days in a quarter or a year that contractors and other professionals are able to install our products. This can vary dramatically based on, among other things, weather events such as rain, snow and extreme temperatures. We have generally experienced lower levels of sales of our housing products in the fourth quarter due to adverse weather conditions in certain markets, which typically reduces the construction and renovation activity during the winter season.

Environmental

As is common in our industry, we are subject to environmental laws and regulations related to the use, storage, handling, generation, transportation, emission, discharge, disposal and remediation of, and exposure to, hazardous and non-hazardous substances and wastes in all of the countries in which we do business. National, state or provincial and local standards regulating air, water and land quality affect substantially all of our manufacturing locations around the world. Compliance with such laws and regulations has required and will continue to require capital expenditures and increase operating costs.

It is our policy to comply with all environmental, health and safety requirements and to provide safe and environmentally sound workplaces for our employees. In some cases, compliance can be achieved only by incurring capital expenditures. In 2024, we made capital expenditures of $43 million related to environmental compliance. We estimate that we will make capital expenditures of approximately $84 million in 2025 and $116 million in 2026, respectively, related to environmental compliance. The expected 2025 and 2026 capital expenditures are relatively higher than the amounts we have spent related to environmental compliance in recent years in large part due to capital expenditures related to previously existing and new Environmental Protection Agency (the "EPA") regulations, including the EPA's 2024 update to the hazardous organic national emission standards for hazardous air pollutants ("NESHAPs"). The remainder of the 2025 and 2026 estimated expenditures are related to equipment replacement and upgrades. We anticipate that stringent environmental regulations will continue to be imposed on us and the industry in general.

From time to time, we receive notices or inquiries from government entities regarding alleged violations of environmental laws and regulations pertaining to, among other things, the disposal, emission and storage of chemical substances, including hazardous wastes. Pursuant to Item 103 of the SEC's Regulation S-K, the following environmental matters involve a governmental authority as a party to the proceedings and potential monetary sanctions that we believe could exceed $1 million (which is less than one percent of our current assets on a consolidated basis as of December 31, 2024):

•Natrium Facility Discharge Investigation. To resolve alleged violations associated with exceedances of discharge limits under the Natrium facility's National Pollutant Discharge Elimination System ("NPDES") permit effective August 2020, we have entered into enforcement negotiations with the West Virginia Department of Environmental Protection ("WVDEP"). The resolution of this matter may involve a penalty in excess of $1 million.

•Sulphur Brine Dome. Westlake owns and operates salt solution-mining caverns at the Sulphur Brine Dome in Sulphur, Louisiana. The Louisiana Department of Energy and Natural Resources ("LDENR") issued Compliance Order No. IMD 2022-027 and several supplements to that order, the latest in October 2023, in response to pressure anomaly events in two of our brine caverns. These brine caverns were not active, operating wells but were under ongoing, post-operational monitoring requirements. The compliance order and supplements thereto have required us to undertake various activities related to response planning, monitoring, investigation and mitigation of potential impacts in the event of future cavern pressure anomalies or failures. Since December 2022, continuous brine injection has maintained cavern pressure while we continue to pursue active monitoring, studies, groundwater monitoring, modeling and other activities under the compliance order and supplements. In September 2023, the Office of Conservation issued an emergency declaration as a conservative step to ensure ample resources are available to the government in its response and management of the evolving circumstances at the Sulphur Brine Dome. In June 2024, the Company's cavern experienced a pressure event. As a result, the cavern required increased rates of brine injection, which ultimately restored cavern pressure but leveled out at a higher injection rate to maintain cavern stability. Citing the recent pressure event, LDENR ordered the Company to begin construction of a dome-wide containment structure, the planning for which was already underway pursuant to the existing compliance order and supplements thereto. The capital costs and expenditures required to comply with the compliance orders and supplements have been and will continue to be incurred. In response to these orders, the Company reserved approximately $28 million in connection with monitoring wells and other remedial activities. At this time, the Company is unable to estimate the impact that other ongoing expenditures or future injunctive relief ordered by the government could have on the Company's financial condition, results of operations or cash flows.

Also see our discussion of our environmental matters contained in Item 1A, "Risk Factors" below, Item 3, "Legal Proceedings" below and Note 21 to our consolidated financial statements included in Item 8 of this Form 10-K.

Human Capital

Westlake is committed to acting in a safe, ethical, environmentally, and socially responsible manner. We have been a public company for 20 years, but we still think of our employees as members of our extended family. We value the integrity, creativity, dedication and diversity of ideas that our employees bring to work every day.

Diversity and Inclusion (D&I)

As a global company, we recognize the diversity of our employees, customers and communities, and believe in creating an inclusive environment that represents a broad spectrum of backgrounds and cultures. A significant portion of our management team and our Board of Directors comes from diverse backgrounds, and we are focused on hiring and retaining diverse and talented employees. Our Board of Directors has charged the Compensation Committee with oversight responsibility of the Company's D&I efforts.

As an Asian American and Pacific Islander ("AAPI")-controlled business, we feel a special commitment to ensuring that Westlake continues to offer opportunities for employees of all backgrounds and experiences. As of December 31, 2024, approximately 35% of our employees in the United States and Canada self-identified as Black, Indigenous, Hispanic, or AAPI. Although we do not collect race and ethnicity data of our workforces in Latin America, Europe, and Asia, we know that we are a diverse, multinational company.

Training and Professional Development

As part of our retention and promotion efforts, we invest in internal leadership development. Westlake regularly provides its employees with a blend of live, virtual, and digital training opportunities. Depending on an employee's position and job responsibilities, these training opportunities include safety training, technical courses, compliance training relating to company policies, business and professional development training, and professional growth classes. In addition, we periodically conduct employee surveys to gauge employee engagement and identify areas for additional focus.

Headcount

As of December 31, 2024, we had approximately 15,540 employees in the following areas:

Our employees are distributed across 19 countries. As of December 31, 2024, approximately 68% were employed in the United States. Approximately 27% ofour employees are represented by labor unions, including works councils in Europe, and our collective bargaining agreements in Europe, North America and Asia expire at various times through 2026. On November 1, 2024, bargaining unit employees of Local Lodge No. 2781 of the International Association of Machinists and Aerospace Workers (IAM) began a strike at our Calvert City, Kentucky, facility, after the IAM members, who work in the facility's ethylene and chlorine units, did not accept our final offer for a new collective bargaining agreement. The ethylene and chlorine units at Calvert City continued to operate without disruption with the use of management and other salaried personnel. The strike ended on November 8, 2024, after the IAM accepted our offer for a new collective bargaining agreement. This specific work stoppage notwithstanding, we believe that our relationship with our employees and unions is open and positive.

Attracting, developing and retaining talented people is crucial to executing our strategy. Our ability to recruit and retain such talent depends on a number of factors, including compensation and benefits, career opportunities and work environment. We provide our employees with competitive compensation packages, development programs that enable continued learning and growth, and comprehensive and competitive benefit packages worldwide. Our compensation and benefits arrangements generally are tailored to local markets of operation.

Health and Safety

The health and safety of our employees and our operations is our highest priority. Our health and safety programs are designed around global standards with appropriate variations addressing the multiple jurisdictions and regulations, specific hazards and unique working environments of our manufacturing, research and development, and administrative office locations. We require each of our locations to perform regular safety audits to ensure proper safety policies, program procedures, analyses and training are in place.

Our focus on safety starts at the top with our Board of Directors. Safety is a key performance indicator that is reported on and discussed at every Board meeting. Our Health, Safety and Environment ("HSE") team plays a pivotal role in overseeing all related policy protections, risk identification and other aspects of our business.

Several of our U.S. manufacturing sites have been recognized by the U.S. Occupational Safety & Health Administration's ("OSHA") Voluntary Protection Program for their low injury rates, employee engagement, and safety programs. Several of our manufacturing sites have achieved ISO 45001 certification, which are internationally recognized standards for Occupational Health and Safety.

Intellectual Property and Technology

We rely upon both trademark and service mark protection to protect our brands, and have registered or applied to register many of these on a world-wide basis. We have over 1,700 active and pending trademark registrations worldwide for our various business segments. We also rely on a combination of patents and un-patented proprietary know-how and trade secrets to preserve our competitive technology position in the market. We have over 1,300 issued patents and pending-patent applications in the United States and several other countries. While some of our production capacity operates under licenses from third parties, other parts of our production operate under technology that was developed internally. Consequently, we offer our own independently developed technology for licensing when the opportunity makes sense on a commercial basis. Although the Company considers its patents, licenses, trademarks and trade secrets in the aggregate to constitute a valuable asset that provides competitive advantage to us, we do not regard any one of our businesses as being materially dependent upon any single or group of related patents, trademarks, licenses, or trade secrets.

Available Information

Our website address is www.westlake.com. Our website content is available for information purposes only. It should not be relied upon for investment purposes, nor is it incorporated by reference in this Form 10-K. We make available on this website under "Investor Relations/Financials," free of charge, our proxy statements, annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those materials as soon as reasonably practicable after we electronically file those materials with, or furnish those materials to, the SEC. The SEC also maintains a website at www.sec.gov that contains reports, proxy statements and other information regarding SEC registrants, including us.

We intend to satisfy the requirement under Item 5.05 of Form 8-K to disclose any amendments to our Code of Ethics and any waiver from a provision of our Code of Ethics by posting such information on our website at www.westlake.com under "Investor Relations/Governance."