Owens Corning (OC) Business

ITEM 1. BUSINESS

Unless the context requires otherwise, the terms “Owens Corning,” “Company,” “we,” “its,” and “our” in this Annual Report on Form 10-K refer to Owens Corning and its subsidiaries.

OVERVIEW

Owens Corning is a building products leader committed to building a sustainable future through material innovation. Our products provide durable, sustainable, and energy-efficient solutions that leverage our unique capabilities and market-leading positions to help our customers win and grow. Our roofing products and systems enhance curb appeal and protect people’s homes. Our insulation products conserve energy and improve acoustics, fire resistance and air quality in the spaces where people live, work and play. Our doors and door systems provide comfort, safety and style for the interior and exterior of homes.

We are global in scope, human in scale with approximately 25,000 total employees in 31 countries dedicated to generating value for our customers and shareholders and making a difference in the communities where we work and live. Founded in 1938 and based in Toledo, Ohio, Owens Corning recorded net sales in 2025 of $10.1 billion.

Glass Reinforcements Divestiture

On February 13, 2025, the Company entered into a definitive agreement ("GR Agreement") for the sale of our global glass reinforcements (“GR”) business for a purchase price of approximately $436 million, less costs to sell. As of December 31, 2025, the estimated purchase price was $474 million, net of cash, less costs to sell. The change since signing is due to the changes in customary and transaction-specific price adjustments which are subject to further changes through the date of the final closing adjustments. The GR business, historically part of the Company’s Composites segment, manufactures, fabricates, and sells glass fiber reinforcements for a wide variety of applications in wind energy, infrastructure, industrial, transportation and consumer markets. The sale will complete Owens Corning’s review of strategic alternatives for the business, as previously announced on February 9, 2024, and aligns with the strategy to reshape the Company to focus on building products in North America and Europe. The transaction is expected to close in the first few months of 2026 and is subject to customary regulatory approvals and other conditions.

The transaction represents a strategic shift that has a major effect on the Company's operations and financial results. Effective January 1, 2025, the GR business’s financial results are reflected in the Company’s consolidated financial statements as discontinued operations for all periods presented.

Changes in Reportable Segments

Effective January 1, 2025, due to a strategic shift in how we manage our business as a result of the GR Agreement and the classification of the GR business as a discontinued operation, we changed the composition of our reportable segments. As a result, all prior period information was recast to reflect this change. The Company now has three reportable segments: Roofing, Insulation and Doors.

Masonite Acquisition

On May 15, 2024, the Company acquired all of the outstanding shares of Masonite International Corporation (“Masonite”), a leading global designer, manufacturer, marketer and distributor of interior and exterior doors and door systems for the residential new construction and residential repair and remodeling markets. The addition of Masonite's market-leading doors business, reported as the Doors segment, creates a new growth platform for the Company, strengthening the Company's position in building and construction and expanding its offering of branded residential building products.

SEGMENT OVERVIEW

At December 31, 2025, the Company had an integrated business model with three reportable segments: Roofing, Insulation, and Doors, which accounted for approximately 43%, 36% and 21% of our total reportable segment net sales, respectively, in 2025.

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Roofing

Our primary products in the Roofing segment are laminate asphalt roofing shingles. Other products include roofing components, composite lumber and oxidized asphalt primarily used in residential construction. Roofing also manufactures and sells glass mat and specialty veil materials used in building and construction applications We have been able to service the growing demand for longer lasting, aesthetically attractive laminate products with efficient capital investment.

We sell shingles and roofing components primarily through distributors, home centers and lumberyards in the United States. Oxidized asphalt is a significant input used in the production of our asphalt roofing shingles. We are vertically integrated and have manufacturing facilities that process asphalt for use in our roofing shingles manufacturing process. In addition, we sell processed asphalt to other shingle manufacturers, to roofing contractors for built-up roofing asphalt systems and to manufacturers in a variety of other industries, including automotive, chemical, rubber and construction. Asphalt input costs and third-party asphalt sales prices are correlated to crude oil prices.

Glass nonwoven mat is a significant input used in the production of our asphalt shingles. The mat uses wet use chopped strand produced by our Insulation segment. We also sell glass nonwoven mat and specialty veil materials to downstream manufacturers for the production of various applications, including vinyl flooring, gypsum wall boards, ceiling tiles and battery separators. These customers span across many industries including building and construction, industrial and infrastructure and renewable energy.

Demand for products in our Roofing segment is generally driven by both residential repair and remodeling activity and by new residential construction. Roofing damage from major storms can significantly increase demand in this segment. As a result, sales in this segment do not always follow seasonal home improvement, remodeling and new construction industry patterns.

Our Roofing segment competes primarily with asphalt shingle manufacturers in the United States. According to various industry reports and Company estimates, Owens Corning’s Roofing segment is the second largest producer of asphalt roofing shingles in the United States. Principal methods of competition include innovation and product design, breadth of product offering, proximity to customers, quality and price.

Our manufacturing operations are generally continuous in nature, and we warehouse much of our production prior to sale since we operate with relatively short delivery cycles. One of the raw materials important to this segment is sourced from a sole supplier. We have a long-term supply contract for this material and have no reason to believe that any availability issues will exist. If this supply was to become unavailable, our production could be interrupted until such time as the supplies again became available or the Company reformulated its products. Additionally, the supply of asphalt, another significant raw material in this segment, has been constricted at times. Although this has not caused a significant interruption of our production in the past, prolonged asphalt shortages would restrict our ability to produce products in this segment.

Insulation

Our insulating products provide a variety of benefits such as energy conservation, thermal functionality, improved acoustical performance and convenience of installation and use. Our Insulation segment includes a diverse portfolio of high, mid and low-temperature products with a geographic mix of United States, Canada, Europe and Latin America, a market mix of residential, commercial, industrial and other markets, and a channel mix of retail, contractor and distribution.

Our products in the North American residential market include thermal and acoustical batts, loosefill insulation, spray foam insulation, wet use chopped strand, foam sheathing and accessories, and are sold under well-recognized brand names and trademarks, such as Owens Corning PINK® Next Gen™ FIBERGLAS™ Insulation. Our products in non-residential markets include glass fiber pipe insulation, energy efficient flexible duct media, bonded and granulated stone wool insulation, cellular glass insulation and foam insulation used in above- and below-grade construction applications, and are sold under well-recognized brand names and trademarks, such as FOAMULAR®, FOAMGLAS® and Paroc®. We sell our insulation products primarily to insulation installers, home centers, lumberyards, retailers and distributors in the United States, Canada, Europe and Latin America.

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Demand for Owens Corning’s insulating products is driven by North American new residential construction, repair and remodeling activity, non-residential construction activity in the United States, Canada, Europe and Latin America, and increasingly stringent building codes and the growing need for energy efficiency. Demand in the segment typically follows seasonal home improvement, remodeling and renovation and residential, non-residential construction industry patterns. Demand for residential insulation in North America typically follows housing starts on a three-month lagged basis, although the new residential construction cycle can elongate due to labor availability and other factors beyond our control. The peak season for home construction and remodeling in our geographic markets generally corresponds with the second and third calendar quarters. Demand for non-residential applications is closely correlated to industrial production growth and overall economic conditions in the markets we serve.

Our Insulation segment competes primarily with fiberglass insulation manufacturers in the United States, with an international presence in Canada, Europe and Latin America. According to industry reports and Company estimates, Owens Corning is North America’s largest producer of residential, commercial and industrial fiberglass insulation. Principal methods of competition include innovation and product design, service, location, quality, price and compatibility of systems solutions.

Doors

Our primary products in the Doors segment are residential interior and exterior doors made of wood, glass, fiberglass and metal, and door components such as frames, sills, weather-stripping, hinges and locks. Other products in this segment are aluminum-framed glass doors and window solutions for luxury homes. Our doors provide a range of benefits including energy efficiency, comfort, privacy, security and curb appeal.

We serve the needs of the residential repair, remodel and new construction markets in the United States, Canada and the United Kingdom. Doors are sold through wholesale and retail distribution channels. In the wholesale channel, we sell through distribution partners to homebuilders, contractors, lumberyards, dealers and building products retailers. One-step distributors sell doors directly to homebuilders and remodeling contractors, while two-step distributors purchase doors in bulk quantities for local door dealers who often perform additional value-added services such as pre-hanging or pre-finishing the door before installation. The retail channel serves consumers and contractors through retail home centers, both in-store and online.

Demand for products in the Doors segment is driven by new residential construction and overall economic conditions in the markets we serve. The Doors segment’s vertically integrated operations extend from raw material to final assembly and fabrication. According to various industry reports and Company estimates, Owens Corning is one of North America’s largest producers of interior and exterior doors. Primary methods of competition include service, quality, innovation, price and product customization.

GENERAL

Intellectual Property

The Company relies on a combination of intellectual property laws, as well as confidentiality procedures and contractual provisions, to protect our intellectual property, proprietary technology and our brands. Through continuous and extensive use of the color PINK® since 1956, Owens Corning became the first owner of a single color trademark registration in the U.S. In addition to our Owens Corning and PINK® brands, the Company has registered, and applied for the registration of, U.S. and international trademarks, service marks and domain names. Additionally, the Company owns numerous U.S. and international patents and patent applications, covering certain of our proprietary technology resulting from research and development efforts. Over time, the Company has assembled a portfolio of intellectual property rights including patents, trademarks, service marks, copyrights, domain names, know-how and trade secrets covering our products, services and manufacturing processes. Our proprietary technology is not dependent on any single or group of intellectual property rights and the Company does not expect the expiration of existing intellectual property to have a material adverse effect on the business as a whole. The Company believes the duration of our patents is adequate relative to the expected lives of our products. Although the Company protects its intellectual property and proprietary technology, any significant impairment of, or third-party claim against, our intellectual property rights could harm our business or our ability to compete.

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Environmental Control

Owens Corning has established policies and procedures that are intended to ensure that its operations are conducted in compliance with all relevant laws and regulations and that enable the Company to meet its high standards for corporate sustainability and environmental stewardship. Our manufacturing facilities are subject to numerous foreign, federal, state and local laws and regulations relating to the presence of hazardous materials, pollution and protection of the environment, including emissions to air, reductions of greenhouse gases, discharges to water, management of hazardous materials, handling and disposal of solid wastes, use of chemicals in our manufacturing processes and remediation of contaminated sites. All Company manufacturing facilities are either ISO 14001 certified or deploy environmental management systems based on ISO 14001 principles. The Company’s 2030 Sustainability Goals include targets related to significant global reductions in energy use, water consumption, waste to landfill, and emissions of greenhouse gases, fine particulate matter, and volatile organic air emissions, and protection of biodiversity. The Company is dedicated to continuous improvement in its environmental, health and safety performance and to achieving its 2030 Sustainability Goals.

The Company has not experienced a material adverse effect upon its capital expenditures or competitive position as a result of environmental control legislation and regulations. Operating costs, including labor costs, associated with environmental compliance were approximately $78 million in 2025. The Company continues to invest in equipment and process modifications to remain in compliance with applicable environmental laws and regulations worldwide.

Regulatory activities of particular importance to our operations include those addressing air pollution, water pollution, waste disposal and chemical control. It is possible that new laws and regulations will specifically address climate change, volatile organic compounds, ozone forming emissions and fine particulate matter. New environmental and chemical regulations could impact our ability to expand production or construct new facilities in geographic regions in which we operate. However, based on information known to the Company, including the nature of our manufacturing operations and associated air emissions, at this time we do not expect any of these new laws, regulations or activities to have a material adverse effect on our results of current operations, financial condition or long-term liquidity.

Owens Corning is involved in remedial response activities and is responsible for environmental remediation at a number of sites, including certain of its currently owned or formerly owned plants. These responsibilities arise under a number of laws, including, but not limited to, the Federal Resource Conservation and Recovery Act, and similar state or local laws pertaining to the management and remediation of hazardous materials and petroleum. The Company has also been named a potentially responsible party under the United States Federal Superfund law, similar state or local laws pertaining to the management and remediation of hazardous materials and petroleum. The Company became involved in these sites as a result of government action or in connection with business acquisitions. At the end of 2025, the Company was involved with a total of 25 sites worldwide, including 10 Superfund and state or country equivalent sites and 15 owned or formerly owned sites. None of the liabilities for these sites are individually significant to the Company.

Remediation activities generally involve a potential range of activities and costs related to soil, groundwater and sediment contamination. This can include pre-cleanup activities such as fact finding and investigation, risk assessment, feasibility studies, remedial action design and implementation (where actions may range from monitoring to removal of contaminants, to installation of longer-term remediation systems). A number of factors affect the cost of environmental remediation, including the number of parties involved in a particular site, the determination of the extent of contamination, the length of time the remediation may require, the complexity of environmental regulations, variability in clean-up standards, the need for legal action, and changes in remediation technology. Taking these factors into account, Owens Corning estimates the costs of remediation to be paid over a period of years. The Company accrues an amount on an undiscounted basis, when a liability is probable and reasonably estimable. Actual costs may differ from these estimates for the reasons mentioned above.

Additional Government Laws and Regulations

In addition to environmental laws and regulations, we are subject to various laws and regulations around the world. For example, trade regulations, including tariffs or other import or export restrictions, may increase the cost of some of our raw materials or cross-border shipments, and limit our ability to do business in certain countries or with certain individuals. Our business is also subject to competition laws in the various jurisdictions where we operate, including the Sherman Antitrust Act and related federal and state antitrust laws in the United States, as well as similar foreign laws and regulations. These laws and regulations generally prohibit competitors from fixing prices, boycotting competitors, or engaging in other conduct that unreasonably restrains competition, and such laws and regulations may impact potential business relationships or transactions with third parties in the future. In addition, health and safety regulations have necessitated, and may continue to necessitate, increased operating costs or capital investments to promote a safe working environment. The Company is also required to comply with increasingly complex and changing laws and regulations enacted to protect business and personal data in the United States and other jurisdictions regarding privacy, data protection and data security, including those related to the

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collection, storage, use, transmission and protection of personal information and other consumer, customer, vendor or employee data. Further, an increasing number of laws and regulations focused on product and chemical hazards, including regulations concerning the impact of product manufacturing and use on climate change, and resulting preferential product selection could also impact our ability to manufacture and sell certain products or require significant research and development investment and capital expenditures to meet regulatory requirements. With respect to the laws and regulations noted above, as well as other applicable laws and regulations, the Company’s compliance programs, may under certain circumstances, involve material investments in the form of additional processes, training, personnel, information technology and capital. For a discussion of the risks associated with certain applicable laws and regulations, see Item 1A, “Risk Factors.”

Sustainability

As a leader in our industry, our goal is to be at the forefront of corporate sustainability efforts. It is our ambition to be a company whose positive impact of our people and products, is greater than the negative impact of manufacturing our products. We work to continually increase the good our people and products do while we concurrently strive to reduce the negative environmental impact of our operations.

Our climate-related sustainability efforts have led Owens Corning to develop a range of strategies and tactics that have had a significant impact on the way we conduct our business. We strive to reduce the greenhouse gas emissions released throughout the entire life cycle of our products by improving the use-phase impacts of our products, making our manufacturing processes more energy-efficient, sourcing more renewable electricity, improving our supply chain logistics, increasing recycled content and developing end-of-life recycling solutions. Together, this work helps to reduce the environmental impact of our operations and lowers the embodied carbon in our products – an attribute of growing importance to our customers.

Many of Owens Corning’s products are made using heavy, industrialized manufacturing processes. While we strive to continue our progress to reduce our impact, our factories produce various emissions, including greenhouse gases. Owens Corning is subject to or has chosen to voluntarily participate in Emissions Trading Schemes around the world. Broad and gradual tightening of national, regional, and state government limits on emissions could disrupt our access to energy sources or specific raw materials, which in turn could disrupt the manufacturing of products dependent upon them. Owens Corning invests in research and development on climate-related risks and opportunities.

Human Capital Resources

The Company’s long-term success is dependent upon its access to and development of management and primary employees who are sufficiently skilled and capable of the work necessary to achieve the Company’s short- and long-term business objectives. To maintain employee engagement, Owens Corning strives to ensure its people feel valued, included, and engaged – from recruitment to retirement. That is why Owens Corning is dedicated to fostering an environment of learning and growth within a supportive, caring culture. We are committed to providing a safe, healthy workplace and a meaningful, engaging employee experience.

As of December 31, 2025, Owens Corning had approximately 25,000 total employees, of which approximately 11,000 were located outside the United States. Approximately 61% of total hourly employees are subject to collective bargaining agreements. The Company regularly engages its salaried, non-represented and represented primary employees to collect feedback.

Safety and Well-Being

One of our primary objectives is the safety and well-being of our employees. Working safely is an unconditional, organization-wide expectation at Owens Corning, which we believe directly benefits employees’ lives, improves our manufacturing processes and reduces our costs. The Company maintains comprehensive safety programs focused on identifying hazards and eliminating risks that can lead to severe injuries. Since 2023, the Company has utilized its employee-developed “Safer Together” initiative, which is intended to increase employee focus and collective engagement on safety. One of our primary safety measures is the Recordable Incident Rate (“RIR”) as defined by the United States Bureau of Labor Statistics. For the year ended December 31, 2025, our RIR, including the Doors segment, was 0.60, compared to 0.48 as reported in the same period in the prior year, which excluded the impact from our Doors segment as a result of the Masonite acquisition.

Additionally, with our Healthy Living platform, we provide a multifaceted well-being program designed to drive sustainable, long-term change, improve the health and lives of employees, and strengthen the culture and work experience.

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Employee Performance and Related Objectives

We also focus on evaluating and managing employee performance, development, succession planning and turnover. Our goal is to create a high-performance culture and teams that are diverse, capable and engaged. We strive to have clear objectives, effective performance management, and a structure that includes regular feedback, talent reviews, succession planning, development, and compensation analysis.

Corporate Culture

Another objective we pursue is maintaining a corporate culture focused on inclusion and diversity, ethics and compliance, training and positive employee relations and engagement. The Company believes its success and sustainability are enhanced by an inclusive and diverse workforce. We believe that inclusion and diversity add value to the business by fostering an environment that leads to high engagement and innovative thinking in the workplace.

Ethics and compliance efforts include our support of the Owens Corning Code of Conduct (“Code of Conduct”), which is dedicated to encouraging compliance with a range of legal guidelines and our corporate values. Our training efforts encompass the Code of Conduct and other areas of compliance and development as relevant to employees. We also seek to foster positive and productive relations with the labor organizations representing them.

Owens Corning employees contribute service hours to boards, special causes and nonprofit organizations in the communities where they live and operate. These programs aim to enable the Company’s employees to connect with the community, further improve its reputation locally and globally, and instill a sense of pride in the workforce.

AVAILABILITY OF INFORMATION

Owens Corning makes available, free of charge, through its website, the Company’s Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and all amendments to those reports as soon as reasonably practicable after such material is electronically filed with or furnished to the Securities and Exchange Commission (the "SEC"). These documents are available through the Investor Relations page of the Company’s website at www.owenscorning.com. Copies of any materials we file with the SEC can also be obtained free of charge through the SEC’s website at http://www.sec.gov. The information on our website is not, and will not be deemed to be, a part of this Annual Report on Form 10-K or incorporated into any of our other filings with the SEC.