Summit Materials : Second Quarter 2021 Earnings Call Presentation

Q2 2021 Results Presentation

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Forward-Looking Statements

This presentation includes "forward-looking statements" within the meaning of the federal securities laws, which involve risks and uncertainties. Forward-looking statements include all statements that do not relate solely to historical or current facts, and you can identify forward-looking statements because they contain words such as "believes," "expects," "may," "will," "outlook," "should," "seeks," "intends," "trends," "plans," "estimates," "projects" or "anticipates" or similar expressions that concern our strategy, plans, expectations or intentions. All statements made relating to our estimated and projected earnings, margins, costs, expenditures, cash flows, growth rates and financial results are forward-looking statements. These forward-looking statements are subject to risks, uncertainties and other factors that may cause our actual results, performance or achievements to be materially different from future results, performance or achievements expressed or implied by such forward-looking statements. We derive many of our forward-looking statements from our operating budgets and forecasts, which are based upon many detailed assumptions. While we believe that our assumptions are reasonable, it is very difficult to predict the effect of known factors, and, of course, it is impossible to anticipate all factors that could affect our actual results. In light of the significant uncertainties inherent in the forward-looking statements included herein, the inclusion of such information should not be regarded as a representation by us or any other person that the results or conditions described in such statements or our objectives and plans will be realized. Important factors could affect our results and could cause results to differ materially from those expressed in our forward-looking statements, including but not limited to the factors discussed in the section entitled "Risk Factors" in Summit Materials, Inc.'s ("Summit Inc.") Annual Report on Form 10-K for the fiscal year ended January 2, 2021 as filed with the Securities and Exchange Commission (the "SEC), and any factors discussed in the section entitled "Risk Factors" in any of our subsequently filed SEC filings; and the following: the impact of the coronavirus ("COVID-19") pandemic on our business, or any similar crisis; our dependence on the construction industry and the strength of the local economies in which we operate; the cyclical nature of our business; risks related to weather and seasonality; risks associated with our capital-intensive business; competition within our local markets; our ability to execute on our acquisition strategy, successfully integrate acquisitions with our existing operations and retain key employees of acquired businesses; our ability to implement and successfully execute on our Elevate Summit Strategy; our dependence on securing and permitting aggregate reserves in strategically located areas; declines in public infrastructure construction and delays or reductions in governmental funding, including the funding by transportation authorities and other state agencies particularly if such are not augmented by federal funding or if the federal government fails to act on a highway infrastructure bill; our reliance on private investment in infrastructure, which may be adversely affected by periods of economic stagnation and recession; environmental, health, safety and climate change laws or governmental requirements or policies concerning zoning and land use; costs associated with pending and future litigation; rising prices for commodities, labor and other production and delivery inputs as a result of inflation or otherwise; conditions in the credit markets; our ability to accurately estimate the overall risks, requirements or costs when we bid on or negotiate contracts that are ultimately awarded to us; material costs and losses as a result of claims that our products do not meet regulatory requirements or contractual specifications; cancellation of a significant number of contracts or our disqualification from bidding for new contracts; special hazards related to our operations that may cause personal injury or property damage not covered by insurance; unexpected factors affecting self-insurance claims and reserve estimates; our substantial current level of indebtedness, including our exposure to variable interest rate risk; our dependence on senior management and other key personnel, and our ability to retain and attract qualified personnel; supply constraints or significant price fluctuations in the electricity and petroleum-based resources that we use, including diesel and liquid asphalt; climate change and climate change legislation or other regulations; unexpected operational difficulties; interruptions in our information technology systems and infrastructure, including cybersecurity and data leakage risks; and potential labor disputes, strikes, other forms of work stoppage or other union activities. All subsequent written and oral forward-looking statements attributable to us, or persons acting on our behalf, are expressly qualified in their entirety by these cautionary statements. Any forward-looking statement that we make herein speaks only as of the date of this presentation. We undertake no obligation to publicly update or revise any forward-looking statement as a result of new information, future events or otherwise, except as required by law.

Non-GAAP Financial Measures

Included in this presentation are certain non-GAAP financial measures, such as Adjusted EBITDA, Adjusted EBITDA Margin, Return on Invested Capital, ROIC Margin, Net Debt, Adjusted Cash Gross Profit, Adjusted Cash Gross Profit Margin, Adjusted Diluted Net Income (Loss)and Net Leverage, designed to complement the financial information presented in accordance with U.S. GAAP because management believes such measures are useful to investors. These non-GAAP financial measures should be considered only as supplemental to, and not superior to, financial measures provided in accordance with GAAP. Please refer to the appendix of this presentation for a reconciliation of the historical non-GAAP financial measures included in this presentation to the most directly comparable financial measures prepared in accordance with GAAP.

Reconciliations of the non-GAAP measures used in this presentation are included or described in the tables attached to the appendix. Because GAAP financial measures on a forward-looking basis are not accessible, and reconciling information is not available without unreasonable effort, we have not provided reconciliations for forward-lookingnon-GAAP measures. For the same reasons we are unable to address the probable significance of the unavailable information, which could be material to future results.

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Agenda

Safe Harbor Disclosure

Karli Anderson, EVP, ESG & Head of Investor Relations

Business Update

Anne Noonan, CEO

Financial Update

Brian Harris, CFO

Management Outlook

Anne Noonan, CEO

Q&A

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Q2 Results & Elevate Summit Success

Summit Q2 Record Net Revenue and Adjusted EBITDA

FINANCIAL RESULTS

• Record Net Revenue of $618.5M
• Net Income of $57.8M
• Record Adjusted EBITDA of $163.8M
• Adj Cash Gross Profit Margin of 32.4%

VOLUME Vs Q2 2020

• Aggregates +14.7%
• Cement +8.3%
• Ready-Mix+6.3%
• Asphalt -11.3% [due primarily to divestiture]

ELEVATE SUMMIT GOALS

• Leverage improved to 3x, an improvement of 0.2x q/q and 0.5x y/y
• 4 divestitures completed in Q2; 5 year to date, $103.6M proceeds
• Expect organic growth to offset divestitures; no change to Outlook

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Q2 2021 Results vs Q2 2020 Reflect Favorable Market Conditions

West Segment	East Segment	Cement Segment
Record Net Revenue of $313.6M, up 5%	Record Net Revenue of $219.1M, up 9%	Net Revenue of $85.8M, up 13%
Adj EBITDA of $78.8M, in-line	Adj EBITDA of $57.3M, up 7%	Adj EBITDA of $39.4M, up 11%
 Higher aggregates and ready-mix volume and	 Higher aggregates and asphalt volume and	 Higher cement volume and price
price partially offset by fewer working days for	price partially offset by lower ready-mix on	 Green America Recycling continues to ramp to
Texas due to wet conditions	fewer windfarm projects	full production; GAR expansion underway

Kilgore, West Region	Cornejo, East Region	Continental Cement, Davenport, IA

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