Cornerstone Building Brands : 3rd Quarter 2020 Financial Results

3Q 2020 Earnings Presentation

November 10, 2020

Disclaimers

Forward-Looking Statements

Certain statements and information in this presentation may constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as "believe," "anticipate," "guidance," "plan," "potential," "expect," "should," "will," "forecast," "target" and similar expressions are forward-looking statements within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995. These forward-looking statements reflect our current expectations, assumptions and/or beliefs concerning future events. As a result, these forward-looking statements rely on a number of assumptions, forecasts, and estimates and, therefore, these forward-looking statements are subject to a number of risks and uncertainties that may cause the Company's actual performance to differ materially from that projected in such statements. Such forward-looking statements may include, but are not limited to, statements concerning our market commentary and expectations for residential and non-residential end markets and our financial outlook and guidance, including our fourth quarter 2020 forecasted net sales, gross profit, and Adjusted EBITDA, and our fiscal year 2020 forecasted capital spending, cash interest expense, cash tax expense, benefits from primary working capital and cash restructuring costs. Among the factors that could cause actual results to differ materially include, but are not limited to, industry cyclicality and seasonality and adverse weather conditions; challenging economic conditions affecting the nonresidential construction industry; downturns in the residential new construction and repair and remodeling end markets, or the economy or the availability of consumer credit; volatility in the United States ("U.S.") economy and abroad, generally, and in the credit markets; the outbreak of a health epidemic or pandemic, including the coronavirus disease 2019 ("COVID-19") pandemic; precautions taken due to the recent COVID-19 pandemic that could harm our business; impairment of goodwill and/or intangible assets; our ability to successfully develop new products or improve existing products; the effects of manufacturing or assembly realignments; seasonality of the business and other external factors beyond our control; commodity price volatility and/or limited availability of raw materials, including steel, PVC resin, glass and aluminum; our ability to identify and develop relationships with a sufficient number of qualified suppliers and to avoid a significant interruption in our supply chains; retention and replacement of key personnel; enforcement and obsolescence of our intellectual property rights; costs related to compliance with, violations of or liabilities

under environmental, health and safety laws; changes in building codes and standards; competitive activity and pricing pressure in our industry; our ability to make strategic acquisitions accretive to earnings; our ability to carry out our restructuring plans and to fully realize the expected cost savings; global climate change, including legal, regulatory or market responses thereto; breaches of our information system security measures; damage to our computer infrastructure and software systems; necessary maintenance or replacements to our enterprise resource planning technologies; potential personal injury, property damage or product liability claims or other types of litigation; compliance with certain laws related to our international business operations; increases in labor costs, potential labor disputes, union organizing activity and work stoppages at our facilities or the facilities of our suppliers; significant changes in factors and assumptions used to measure certain of our defined benefit plan

obligations and the effect of actual investment returns on pension assets; the cost and difficulty associated with integrating and combining acquired businesses; volatility of the Company's stock price; substantial governance and other rights held by the Investors; the effect on our common stock price caused by transactions engaged in by the Investors, our directors or executives; our substantial indebtedness and our ability to incur substantially more indebtedness; limitations that our debt agreements place on our ability to engage in certain business and financial transactions; our ability to obtain financing on acceptable terms; downgrades of our credit ratings; and the effect of increased interest rates on our ability to service our debt. See also the "Risk Factors" in the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2019, Quarterly Reports on Form 10-Q for the quarterly period ended April 4, 2020 and July 4, 2020 and other risks described in documents subsequently filed by the Company from time to time with the SEC, which identify other important factors,

though not necessarily all such factors, that could cause future outcomes to differ materially from those set forth in the forward-looking statements. The Company expressly disclaims any obligation to release publicly any updates or revisions to these forward-looking statements, whether as a result of new information, future events, or otherwise.

Non-GAAP Financial Measures

This presentation includes certain "non-GAAP financial measures" as defined under the Securities Exchange Act of 1934 and in accordance with Regulation G. Management believes the use of such non-GAAP financial measures assists investors in understanding the ongoing operating performance of the Company by presenting the financial results between periods on a more comparable basis. Such non-GAAP financial measures should not be construed as an alternative to reported results determined in accordance with U.S. GAAP. We have included reconciliations of these non-GAAP financial measures to the most directly comparable financial measures calculated and provided in accordance with U.S. GAAP in the Appendix to this presentation. A reconciliation of the forecasted range for Adjusted EBITDA for the fourth quarter of 2020 is not included in this presentation due to the number of variables in the projected range and because we are currently unable to quantify accurately certain amounts that would be required to be included in the GAAP measure or the individual adjustments for such reconciliation. In addition, we believe such reconciliation would imply a degree of precision that would be confusing or misleading to investors.

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We are Committed to Creating Great Communities

• We employ waste solvent and scrap PVC recycling programs that allow reuse of reclaimed wastes back into our manufacturing processes
• We utilize ISO 14001-certified Environmental Management Systems within coil coating facilities
• Invested $2.5 million on pollution control equipment designed to optimize waste heat recovery and reduce energy consumption

• Our Employee Assistance Foundation assists employees in need of emergency financial support & we offer Employee Assistance Programs to all employees
• Our Core Values, Talent Philosophy, and Success Model provide a framework for an inclusive culture
• Our extensive online learning programs provide development for all employees at every level
• Through our Home for Good project, we helped build 500+ homes for those in need of affordable housing

• Governance policies and processes are rooted in our core values of ethics and integrity, and include:
• • Code of Conduct and Ethics
  • Independent Ethics Hotline
  • Anti-Corruption& Trade Compliance Policy Statement & Compliance Guide
  • Corporate Governance Guidelines
• Manage risks utilizing our Enterprise Risk Management and Compliance policies

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Performance Highlights - Financial and Operational Success

Delivered strong third-quarter results:

Achieved sixth consecutive quarter of year-over- year Adjusted EBITDA1 margin expansion in each segment

Earned all-time high 15.8% Adjusted EBITDA margin1 as a percentage of net sales; which is160 basis points of margin expansion over pro forma prior year

Generated quarterly net operating cash flow of $170 million, more than double prior year

Captured approximately $75 million of year over year structural cost improvements on a year-to- date basis

Issued $500 million of senior unsecured notes, enhancing our liquidity profile, strengthening the balance sheet by extending debt maturity profile and improving financial flexibility

Reduced net debt leverage1 ratio to 4.9x, an improvement of 0.9x year-over-year

Performed well operationally: Maintained our value proposition and price leadership in the market

Safety and well-being of key stakeholders remains highest priority

Historic backlog levels in Windows and Siding Segments

Installed two automated window lines in North Brunswick, New Jersey facility increasing capacity by 20% for our largest product line to better serve our residential customers

1 Adjusted financial metrics used in the presentation are non-GAAP measures and refer to the results for 2020 and 2019. Pro forma financial metrics used in this release for results in 2020 and 2019 are also non-
GAAP measures and adjust for other items affecting comparability. See reconciliations of GAAP results to adjusted results and pro forma results in the appendix.	4