GMS : September 2023 Investor Overview

Investor Overview

September 2023

Safe Harbor and Basis of Presentation

Forward-LookingStatement Safe Harbor - This presentation includes "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. You can generally identify forward-looking statements by the Company's use of forward-looking terminology such as "anticipate," "believe," "confident," "continue," "could," "estimate," "expect," "intend," "may," "might," "plan," "potential," "predict," "seek," or "should," or the negative thereof or other variations th ereon or comparable terminology. In particular, statements about the markets in which GMS operates and our products, including potential growth in those markets and products, the economy generally, our ability to continue successfully navigating the evolving operating environment and executing our business, strategic initiatives and priorities and growth potential, future M&A and greenfields, product availability, inflation, capital structure, pricing, volumes, net sales, organic sales, gross margins, incremental EBITDA, Adjusted EBITDA, Adjusted EBITDA margin, interest expense, tax rates, capital expenditures, free cash flow, cash flow generation and working capital management, future financial performance and liquidity, the ability of the Company to grow stronger, the ability to deliver growth, value creation and long-term success, and the Company's cost reduction initiatives and results thereof contained in this presentation may be considered forward-looking statements. Statements about our expectations, beliefs, plans, strategies, objectives, prospects, assumptions or future events or performance may be considered forward-looking statements. The Company has based forward-looking statements on its current expectations, assumptions, estimates and projections. While the Company believes these expectations, assumptions, estimates and projections are reasonable, such forward-looking statements are only predictions and involve known and unknown risks and uncertainties, many of which are beyond its control, including current public health issues that may affect the Company's business. Forward-looking statements involve risks and uncertainties, including, but not limited to, those described in the "Risk Factors" section in the Company's most recent Annual Report on Form 10-K, and in its other periodic reports filed with the SEC. In addition, the statements in this release are made as of September 6, 2023. The Company undertakes no obligation to update any of the forward -looking statements made herein, whether as a result of new information, future events, changes in expectation or otherwise. These forward-looking statements should not be relied upon as representing the Company's views as of any date subsequent to September 6, 2023.

Use of Non-GAAPand Adjusted Financial Information - To supplement GAAP financial information, we use adjusted measures of operating results which are non-GAAP measures. This non-GAAP adjusted financial information is provided as additional information for investors. These adjusted results exclude certain costs, expenses, gains and losses, and we believe their exclusion can enhance an overall understanding of our past financial performance and also our prospects for the future. These adjustments to our GAAP results are made with the intent of providing both management and investors a more complete understanding of our operating performance by excluding non-recurring, infrequent or other non-cash charges that are not believed to be material to the ongoing performance of our business. The presentation of this additional information is not meant to be considered in isolation or as a substitute for GAAP measures of net income, diluted earnings per share or net cash provided by (used in) operating activities prepared in accordance with generally accepted accounting principles in the United States. Please see the Appendix to this presentation for a further discussion on these non -GAAP measures and a reconciliation of these non-GAAP measures to the most directly comparable GAAP measures.

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GMS at a Glance

52yrs

Founded in

1971

300+

Distribution yards

& 100+

Tool Sales, Rentals & Service Centers

$5.3B		$333.0M
FY 2023		FY 2023
Net Sales		Net Income

60+ 7,000+

Leading Brands	GMS Team Members

$665.7M

FY 2023

Adj. EBITDA1

GMS

NYSE Ticker

Symbol

1. For a reconciliation of Adjusted EBITDA to the most directly comparable GAAP metrics, see Appendix.

Information as of April 30, 2023

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Diversified and Balanced End Market Exposure

Diversified exposure across commercial and residential new and repair and remodel construction markets continues to be an advantage

~45%	~55%
Residential	Commercial
•	Single-Family New	•	New Construction
•	Multi-Family New	•	Repair & Remodel
•	Repair & Remodel

While these percentages fluctuate from time to time as market conditions change, the numbers shown reflect the Company's "through the cycle" expectations.

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Providing Value to Contractors and Builders

A leading North American specialty distributor of construction products

GMS provides the products and value-added services to contractors who install wallboard, ceilings, steel framing and other complementary building products

• Expertise across local markets, leveraging scaled North
  American footprint​
• One-stop-shopfor contractors with a broad product offering​
• Critical link between suppliers and a highly fragmented customer base​

Net Sales Breakdown (Fiscal 2023)

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