GMS Investor Conference Presentation Deck

Opportunities for Further Platform Expansion • Opportunity to expand our geographic footprint in under-served and under-penetrated markets through accretive greenfield locations and acquisitions ● ● ● Current footprint comprises over 300 distribution yard locations covering 47 U.S. States and 6 Canadian Provinces; Plus more than 100 AMES store locations At least some level of presence in 78 of the Top 100 U.S. Metropolitan Statistical Areas ("MSA's") and 8 of the Top 10 Canadian Metropolitan Areas ("CMA's") Significant whitespace and underpenetrated markets remaining in both the U.S. and Canada Opportunities to develop "Complementary Products" in markets where GMS already has an established presence to drive further share gains GMS GYPSUM MANAGEMENT & SUPPLY, INC. • California Western Canada Canada Mountain West United States South Central Texas Central Midwest Gulf Coast Map Legend GMS Distribution Location AMES Location Targeted Expansion Area Eastern Canada New England South Florida As of June 2023 2

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