ARMSTRONG WORLD INDUSTRIES INC (AWI) Business

ITEM 1. BUSINESS

Armstrong World Industries, Inc. (“AWI” or the “Company”) is a Pennsylvania corporation incorporated in 1891. When we refer to “we,” “our” and “us” in this report, we are referring to AWI and its subsidiaries.

AWI is an Americas leader in the design and manufacture of innovative interior and exterior architectural applications including ceilings, specialty walls and exterior metal solutions. We manufacture and source products made of numerous materials, including mineral fiber, fiberglass, metal, felt, architectural resin and glass, wood, wood fiber and glass-reinforced-gypsum. We also manufacture ceiling suspension system (grid) products through a joint venture with Worthington Enterprises, Inc. called Worthington Armstrong Venture (“WAVE”).

Reportable Segments

Our operating segments are as follows: Mineral Fiber, Architectural Specialties and Unallocated Corporate.

Mineral Fiber – produces suspended mineral fiber and fiberglass ceiling systems. Our mineral fiber products offer various performance attributes such as acoustical control, rated fire protection, and energy efficiency, along with other health and sustainability features and aesthetic appeal. Ceiling products are primarily sold to resale distributors, ceiling systems contractors and wholesalers, and retailers (including large home centers). The Mineral Fiber segment also includes the results of WAVE, which manufactures and sells suspension system (grid) products and ceiling component products that are invoiced by both AWI and WAVE. Segment results relating to WAVE consist primarily of equity earnings and reflect our 50% equity interest in the joint venture. Ceiling component products consist of ceiling perimeters and trim, in addition to grid products that support drywall ceiling systems, structural and walkable grid systems. For some customers, WAVE sells its suspension system products to AWI for resale to customers. Mineral Fiber segment results reflect those sales transactions. The Mineral Fiber segment also includes all assets and liabilities not specifically allocated to our Architectural Specialties or Unallocated Corporate segment, including all property and related depreciation associated with our Lancaster, Pennsylvania headquarters. Operating results for the Mineral Fiber segment include a significant majority of allocated Corporate administrative expenses that represent a reasonable allocation of general services to support its operations.

Architectural Specialties – designs, produces and sources specialty ceilings, walls, and other interior and exterior architectural applications primarily for use in commercial settings. Products are available in numerous materials, such as metal, felt, architectural resin and glass, wood, wood fiber and glass-reinforced-gypsum in various colors, shapes and designs. These products offer a range of design options and performance attributes such as acoustical control, rated fire protection, light, aesthetic appeal, energy conservation and building performance. We sell standard, premium and customized products, a portion of which are sourced from third-party producers. Architectural Specialties products are sold primarily to direct customers, primarily ceiling systems contractors, and resale distributors. This segment’s revenues are primarily project driven, which can lead to more variability in sales patterns. Operating results for the Architectural Specialties segment include a portion of allocated Corporate administrative expenses that represent a reasonable allocation of general services to support its operations.

Unallocated Corporate – includes certain assets, liabilities, income and expenses that have not been allocated to our other business segments and consists of: cash and cash equivalents, our Overcast Innovations LLC investment and related equity earnings and losses, the net funded status of our U.S. Retirement Income Plan (“RIP”), the estimated fair value of interest rate swap contracts, outstanding borrowings under our senior secured credit facility and income tax balances.

Overview

Our business has been built on providing high-quality, innovative products through a highly effective service model as well as by maintaining strong brand awareness and trust. We are committed to delivering profitable revenue growth, strong cash flow generation and sustainable shareholder value by strengthening our core Mineral Fiber segment and expanding our Architectural Specialties segment into new, adjacent business categories and sectors. Through this strategy, we have delivered consistent growth in mineral fiber sales dollars per unit sold through product innovation, including our Templok® energy saving ceiling tiles, Total Acoustics® solutions and Sustain® family of products, and we have built a broad portfolio of architectural specialties products for ceilings, specialty walls and exterior metal architectural applications. Our growth initiatives continue to focus on market-driven innovation and digital tools to accelerate renovation and further differentiate our products and solutions. In addition, we continue to invest in expanding our Architectural Specialties market and reach capabilities into new adjacencies through both organic investment and acquisitions.

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Acquisitions and Investments in Unconsolidated Affiliates

In December 2025, we acquired all of the issued and outstanding stock of FGM-Parallel LLC (“Parallel”), based in Englewood, Colorado. Parallel is a designer and manufacturer of extruded aluminum products primarily used in exterior architectural applications. The operations, assets and liabilities of Parallel are included in our Architectural Specialties segment.

In September 2025, we acquired all of the issued and outstanding stock of Geometrik Manufacturing, Inc. (“Geometrik”), based in Kelowna, British Columbia, Canada. Geometrik is a designer and manufacturer of wood acoustical ceiling and wall systems. The operations, assets and liabilities of Geometrik are included in our Architectural Specialties segment.

In December 2024, we acquired all of the issued and outstanding stock of A. Zahner Company (“Zahner”), based in Kansas City, Missouri. Zahner is a designer and manufacturer of exterior metal architectural solutions. The operations, assets and liabilities of Zahner are included in our Architectural Specialties segment.

In April 2024, we acquired all of the issued and outstanding membership interests in 3form, LLC (“3form”), based in Salt Lake City, Utah from Hunter Douglas, Inc. 3form is a designer and manufacturer of architectural resin and glass products used for specialty walls, partitions and ceilings. The operations, assets and liabilities of 3form are included in our Architectural Specialties segment.

In January 2024, we entered into a strategic partnership and equity investment in Overcast Innovations LLC (“Overcast”) with McKinstry Essention, LLC whereby we contributed $5.5 million in exchange for an initial 19.5% ownership interest in Overcast (currently 19.2%). Overcast is a solutions company offering prefabricated ceiling cloud systems, modular grid platforms and engineering design services to reduce waste and inefficiencies in the built environment. Our investment and equity earnings and losses in Overcast are included in our Unallocated Corporate segment.

In October 2023, we acquired a portion of the business and certain assets of Insolcorp, LLC (“Insolcorp”), based in Albemarle, North Carolina. Insolcorp develops, tests and manufactures energy saving products deployed in building and roofing installations. The acquired operations, assets and liabilities of Insolcorp are included in our Mineral Fiber segment.

In July 2023, we acquired all of the issued and outstanding stock of BOK Modern, LLC (“BOK”), based in San Rafael, California. BOK is a designer of exterior metal architectural solutions. The operations, assets and liabilities of BOK are included in our Architectural Specialties segment.

Markets

We primarily serve markets in the United States, Canada and Latin America. We believe we are well positioned in the industry sectors and categories in which we operate, often holding a leadership position. Our products compete against mineral fiber and fiberglass ceiling products from other manufacturers, as well as drywall and a wide range of specialty ceiling and exterior metal products. We compete directly with other domestic and international suppliers of these products. The major markets in which we compete are:

Commercial Construction. Our revenue opportunities come from new construction as well as renovation of existing buildings. Most of our revenue comes from the following sectors of commercial construction: office (including data centers), education, healthcare, transportation and retail. We closely monitor publicly available macroeconomic data and trends that provide insight into commercial construction market activity, including, but not limited to, gross domestic product (“GDP”), office vacancy rates, the Architecture Billings Index, new commercial construction starts, government spending, corporate profits and retail sales. Our revenue from new construction can lag behind construction starts by as much as 24 months. We believe that these statistics, taking into account the time-lag effect, provide a reasonable indication of our future revenue opportunity from commercial renovation and new construction. Additionally, we believe that customer preferences for product type, style, color, performance attributes (such as acoustics, energy efficiency, sustainability and health attributes), availability, affordability and ease of installation also affect our revenue.

In our Mineral Fiber segment, we estimate that a majority of our commercial construction market sales are used for existing building renovation purposes by end-users of our products. We classify our renovation opportunities as major renovation projects, which tend to be larger in scope, or repair and remodel projects, which generally involve the replacement of old products with new products. In our Architectural Specialties segment, we estimate that a majority of our commercial construction market sales are used for new building construction by end-users of our products. The end-use of our products is based on management estimates as such information is not easily determinable.

Residential Construction. We also sell a small portion of our products for use in single and multi-family housing. We estimate that existing home renovation work represents the majority of the residential construction market opportunity. Key U.S. statistics that

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indicate market opportunity include existing home sales (a key indicator for renovation opportunity), housing starts, housing completions, home prices, interest rates and consumer confidence.

Customers

We have developed long-standing relationships with our customers based on our product quality, broad product portfolio, design capabilities, service, innovation and brand recognition. We principally sell commercial products to building materials distributors, who re-sell our products to contractors, subcontractors’ alliances, large architect and design firms, and major facility owners. Our design services and sales teams also work directly with architects, design firms and general contractors to ensure our products are included in project specifications. We have important relationships with home center customers, direct customers and certain national account customers, including wholesalers who re-sell our products to dealers who service builders, and maintenance, repair and operating supply (“MRO”) companies.

In 2025, approximately 63% of our consolidated net sales were to building materials distributors. Sales to home center customers accounted for nearly 7% of our consolidated net sales. Our remaining sales were primarily to direct customers, independent retailers, national account customers and online customers.

In September 2025, GMS, Inc., one of our largest distributor customers, was acquired by The Home Depot, Inc. In addition, in October 2025, Foundation Building Materials, Inc., another one of our largest distributor customers, was acquired by Lowe's Companies, Inc.

Gross sales to Lowe's Companies, Inc. (including sales to Foundation Building Materials, Inc.) and The Home Depot, Inc. (including sales to GMS, Inc.) totaled $937.8 million and each individually exceeded 10% of our consolidated gross sales in 2025. Sales to these customers were included in both our Mineral Fiber and Architectural Specialties segment net sales.

Working Capital

We primarily produce goods for inventory and sell on credit to our customers. Generally, we believe our distributors and home center customers carry inventory as needed to meet local or rapid delivery requirements. We sell our products to select, pre-approved customers using customary trade terms that allow for payment in the future. These practices are typical within the industry.

Competition

The markets in which our products are sold are highly competitive. Principal factors of competition include product performance and attributes, product styling, service and price. Competition comes from both domestic and international manufacturers. Additionally, some of our ceiling products compete with alternative products or finishing solutions, namely, drywall and exposed structure (also known as open plenum). Excess industry capacity exists for certain products, which tends to increase price competition. The following companies are our primary competitors:

CertainTeed Corporation (a subsidiary of Saint-Gobain), Chicago Metallic Corporation (owned by Rockwool International A/S), Rockfon A/S (owned by Rockwool International A/S), USG Corporation (owned by Gebr. Knauf KG), Ceilings Plus (owned by USG Corporation), Rulon International, SAS International, and 9Wood.

Raw Materials

We purchase raw materials from numerous suppliers in the ordinary course of business. Our principal raw materials are fiberglass, perlite, recycled paper and starch. Other raw materials we purchase include clays, felt, pigment, resin, wood and wood fiber. We manufacture most of our mineral wool needs at one of our facilities. Finally, we use aluminum and steel in the production of metal products by us and by WAVE, our joint venture that manufactures ceiling and wall grid products.

We also purchase significant amounts of packaging materials and consume substantial amounts of energy, such as electricity and natural gas, and water.

In general, adequate supplies of raw materials are available to all of our operations. However, availability can change for a number of reasons, including environmental conditions, laws and regulations, shifts in demand by other industries competing for the same materials, transportation disruptions and/or business decisions made by, or events that affect, our suppliers. There is no assurance that these raw materials will remain in adequate supply to us.

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Prices for certain high usage raw materials can fluctuate dramatically, including due to tariffs. Cost increases for these materials can have a significant adverse impact on our manufacturing costs. Given the competitiveness of our markets, we may not be able to recover the increased manufacturing costs through increasing selling prices to our customers.

Sourced Products

Some of the products we sell are sourced from third parties. Our primary sourced products include specialty ceiling and exterior metal products. A portion of our sourced products are from suppliers located outside of the U.S., primarily from Europe and the Pacific Rim. Sales of sourced products represented less than 10% of our total consolidated revenue in 2025.

In general, we believe we have adequate supplies of sourced products. However, we cannot guarantee that the supply will remain adequate.

Seasonality

Historically, our sales tend to be stronger in the second and third quarters of our fiscal year due to more favorable weather conditions, customer business cycles and the timing of renovation and new construction activity.

Patent and Intellectual Property Rights

Patent protection is important to our business. We hold a broad collection of intellectual property rights relating to certain aspects of our products and processes developed or perfected within AWI or obtained through acquisitions and licenses. This includes patents, trademarks, designs, copyrights, trade secrets and other forms of intellectual property rights in the U.S. and various foreign countries.

Patent protection extends for varying periods according to the date of patent filing or grant and the legal term of a patent in the various countries where patent protection is obtained. The actual protection afforded by a patent, which can vary from country to country, depends upon the type of patent, the scope of its coverage and the availability of legal remedies. Although we consider that, in the aggregate, our patents, trademarks, designs, copyrights, trade secrets and licenses constitute a valuable asset of material importance to our business, we do not believe we are materially dependent upon any single one of these intellectual property rights.

Certain of our trademarks, including without limitation, , Armstrong®, 3form®, ACOUSTIBuilt®, Arktura®, BŌK Modern®, Calla®, CastWorks®, Cirrus®, Cortega®, DESIGNFlex®, Dune™, Feltworks®, Infusions®, Kanopi®, LightArt®, Lyra®, MetalWorks™, Móz™, Optima®, ProjectWorks®, Soundscapes®, Sustain®, Tectum®, Templok®, Total Acoustics®, Turf®, Ultima®, WoodWorks® and Zahner®, are important to our business because of their significant brand name recognition. Registrations are generally for fixed, but renewable, terms.

In connection with the separation and distribution of our former flooring business into a separate publicly traded company, Armstrong Flooring, Inc. (“AFI”), in 2016, we entered into several agreements with AFI that, together with a plan of division, provided for the separation and allocation of assets between AWI and AFI. These agreements include a Trademark License Agreement and a Transition Trademark License Agreement. Pursuant to the Trademark License Agreement, AWI provided AFI with a perpetual, royalty-free license to use the “Armstrong” trade name and logo. Further, in 2022, as part of the AFI bankruptcy and with AWI consent, all rights, obligations and protections that existed as part of the arrangement with AFI were transferred to AHF Products, LLC (“AHF”) in North America, Zhejiang GIMIG Tech Co., Ltd. in China and various countries throughout the Pacific Rim, India, Russia, Africa, and the geographical regions in the Middle East and Middle Asia and to Braeside Mills Investments Pty Ltd in Australia and New Zealand. During 2024, AWI terminated the license with AHF and sold the flooring specific trademarks previously licensed to AHF. None of these transactions had or are expected to have any material impact on the integrity of the Armstrong trademark.

In connection with the sale of certain subsidiaries comprising our businesses and operations in Europe, the Middle East and Africa (including Russia) (“EMEA”) and the Pacific Rim, including the corresponding businesses and operations conducted by WAVE (collectively, the “Sale”), to Knauf International GmbH (“Knauf”) in 2019, we entered into a royalty-free intellectual property License Agreement with Knauf for its benefit (and, under sublicense, to the buyers of certain businesses divested by Knauf) under which they license certain patents, trademarks and know-how from us for use in certain licensed territories.

We review the carrying value of indefinite-lived trademarks at least annually for potential impairment. See the “Critical Accounting Estimates” section of Management’s Discussion and Analysis of Financial Condition and Results of Operations in Item 7 of this Form 10-K for further information.

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Sustainability and Environmental Matters

As a leading building products manufacturer, we are committed to operating sustainably across all areas of our business. This commitment is reflected in our ongoing initiatives to design and develop sustainable interior and exterior architectural applications, including ceilings, specialty walls and exterior metal solutions. Our sustainability focus reflects our mission to make a positive difference in the lives of people where they live, work, learn, heal and play. Our approach to sustainability is designed to support our strategic priorities, align with stakeholder interests, and be visible and measurable.

Our sustainability program is organized around three program pillars: Healthy and Circular Products, Healthy Planet and Thriving People and Communities.

Our Healthy and Circular Products pillar broadly focuses on ensuring our products are free of chemicals of concern, reducing our products’ water intensity and carbon footprint, improving the circularity of our products so they can be recycled, reused or repurposed, and continuing to invest in solutions that meet customer demand for building products that align with their sustainability goals. These efforts also include our mineral fiber ceilings recycling program, which aims to divert reclaimed ceiling tiles from landfills. We expect that there will be increased demand over time for products, systems and services that meet evolving regulatory and customer sustainability standards and preferences and decreased demand for products that generate significant greenhouse gas emissions. We also believe that our ability to continue to provide these products, systems and services to our customers, including through our Sustain® portfolio, is aligned with our growth strategy.

Our Healthy Planet pillar broadly focuses on reducing our greenhouse gas footprint, reducing or reclaiming water in our operations, and reducing waste in our operations. These efforts include achieving emissions reductions through operational efficiency and product design improvements and exploring renewable electricity options where we operate. Additionally, we are committed to complying with all environmental laws and regulations that are applicable to our operations.

Our Thriving People and Communities pillar broadly focuses on creating a safe working environment for our employees, increasing our engagement in the communities where we operate, evaluating our benefits and compensation structure for all levels of the organization, promoting and maintaining a diverse, inclusive, talented and thriving workforce, and encouraging and protecting human rights.

The adoption of environmentally responsible building codes and standards such as the Leadership in Energy and Environmental Design (“LEED”) rating system established by the U.S. Green Building Council, has the potential to increase demand for products, systems and services that contribute to sustainable buildings. Many of our products meet the requirements for the award of LEED credits, and we are continuing to develop new products, systems and services to address market demand for products that enable construction of buildings that require fewer natural resources to build, operate and maintain.

In 2025, we published our fifth Sustainability Report which measures our progress towards achieving our 2030 sustainability goals and provides insights into our sustainability efforts. We expect to update our progress regularly. The report is available in the “Sustainability” section of our website, which is listed below. Information in the 2025 Sustainability Report or the Company's website is not incorporated herein by reference.

Human Capital

Workforce Demographics. As of December 31, 2025 and 2024, we had approximately 3,800 and 3,600 full-time and part-time employees, respectively. During 2025, our total voluntary and involuntary turnover rates were approximately 8% and 3%, respectively, for non-production employees and 12% and 7%, respectively, for production employees.

As of December 31, 2025, approximately 54% of our approximately 1,700 production employees in the U.S. were represented by labor unions. Collective bargaining agreements covering approximately 260 employees at one U.S. plant will expire during 2026. We believe that our relations with our employees are constructive and positive.

Employee Health and Safety. Safety is a core value at AWI and our culture is committed to making safety a personal core value for every employee. Our overall goal is to eliminate workplace injuries. We promote and foster an environment of empowerment and sharing throughout the company at all levels and in all locations. We engage our employees on safety with a focus on risk identification and elimination and through tracking various leading indicators. We track Occupational Safety and Health Administration (“OSHA”) recordable injuries and lost time rates by location monthly. We establish safety targets annually, which are tracked and reported to leadership monthly and reviewed with our Board of Directors.

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Compensation, Benefits and Wellness. Employee compensation is based on defined job descriptions and position grades that are evaluated against external market data that we believe is competitive and fair. We offer competitive health and wellness benefits to eligible employees and periodically conduct analyses of plan utilization to further tailor our employee benefits to meet their ongoing needs. In recent years we added parental leave and adoption benefits for all employees and launched a wellness program to promote physical, mental and financial well-being. In addition, we offer on-site wellness screenings at our manufacturing facilities in partnership with our medical provider. Finally, we offer mental well-being support and nutrition and financial wellness education to all employees.

People and Workplace Culture. We believe that an inclusive workplace supports our ability to attract, develop and retain talented employees and is important to our success. This focus is reflected in the Thriving People and Communities Pillar of our Sustainability program, which is led by our Vice President of Talent Sustainability and Talent Acquisition. Through our merit-based selection process, we strive to hire qualified candidates based on skills and experiences to foster a work environment that values collaboration and professionalism. In addition, we engage in events and outreach and provide employee resources to support workforce development and a positive workplace culture across our organization.

Product Innovation

Product innovation activities are important and necessary in helping us improve our products’ competitiveness. Principal product innovation functions include the development and improvement of products and manufacturing processes. We engage in research and development activities with a focus on market-driven product innovation to maintain our competitive position and enable growth, as well as innovation in our manufacturing processes to increase productivity.

Legal and Regulatory Proceedings

Regulatory activities of particular importance to our operations include proceedings under the Comprehensive Environmental Response, Compensation and Liability Act (“CERCLA”), and state Superfund and similar type environmental laws governing existing or potential environmental contamination at two domestically owned locations allegedly resulting from past industrial activity. We are one of several potentially responsible parties in these matters and have agreed to jointly fund the required investigation, while preserving our defenses to the liability. We may also have rights of contribution or reimbursement from other parties or coverage under applicable insurance policies.

Most of our facilities are affected by various federal, state and local environmental requirements relating to the discharge of materials or the protection of the environment. We make expenditures necessary for compliance with applicable environmental requirements at each of our operating facilities. We have not experienced a material adverse effect upon our capital expenditures or competitive position as a result of environmental control legislation and regulations.

From time to time, we are involved in various other lawsuits, claims, investigations and other legal matters that arise in the ordinary course of business, including matters involving our products, intellectual property, relationships with suppliers, relationships with distributors, relationships with competitors, employees and other matters. In connection with those matters, we may have rights of contribution or reimbursement from other parties or coverage under applicable insurance policies. When applicable and appropriate, we will pursue coverage and recoveries under those policies but are unable to predict the outcome of those demands. While complete assurance cannot be given to the outcome of any proceedings relating to these matters, we do not believe that any current claims, individually or in the aggregate, will have a material adverse effect on our financial condition, liquidity or results of operations.

Liabilities for environmental matters that we consider probable and for which a reasonable estimate of the probable liability could be made were $4.1 million and $4.6 million as of December 31, 2025 and 2024, respectively. See Note 26 to the Consolidated Financial Statements and Risk Factors in Item 1A of this Form 10-K, for information regarding the possible effects that compliance with environmental laws and regulations may have on our businesses and operating results.

Website

We maintain a website at https://www.armstrong.com. Information contained on our website is not incorporated into this document. Our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and all amendments to those reports and other information about us are available free of charge through this website. Documents filed with the SEC are available on our website as soon as reasonably practicable after the reports are electronically filed with the SEC. We also file annual, quarterly and current reports, proxy statements and other information with the SEC. The SEC maintains a website that contains reports, proxy and information statements, and other information regarding issuers, including us, that file electronically with the SEC at https://sec.gov. Reference in this Form 10-K to our website and the SEC’s website is an inactive text reference only.