Exhibit 99.1

FOR IMMEDIATE RELEASE

GMS REPORTS FIRST QUARTER FISCAL 2021 RESULTS

Strong Execution Results in Higher Profit Margins Despite Top-Line Challenges Related to COVID-19

Tucker, Georgia, September 3, 2020. GMS Inc. (NYSE:GMS), a leading North American specialty distributor of interior building products, today reported financial results for the first quarter of fiscal 2021 ended July 31, 2020.

First Quarter Fiscal 2021 Highlights

(Comparisons are to the first quarter of fiscal 2020, except where noted.)

“Our first quarter results reflect outstanding execution by our entire team against the backdrop of a business environment that remained challenging throughout the period,” said John C. Turner, Jr., President and Chief Executive Officer. “Despite lower sales resulting from the impact of the COVID-19 pandemic on our business and overall industry, we generated higher net income and Adjusted net income compared to the first quarter of last fiscal year, as well as year-over-year expansion of both gross margin and Adjusted EBITDA margin. This improvement is a result of the rapid alignment of our cost structure to current demand, our balanced product and market mix, which has been strengthened through execution of our growth initiatives, and a relentless focus on serving our customers with operational excellence. At the same time, the health and safety of our employees, business partners and communities remains our top priority, and all of us at GMS continue to express our gratitude to all those who have been and continue to be on the frontlines every day during these unprecedented times.”

Mr. Turner continued, “While there is continued uncertainty regarding the near-term outlook for the construction industry and the broader economy, I am confident in our team’s ability to continue to quickly and nimbly address challenges and leverage opportunities. We firmly believe the foundation we have built at GMS, coupled with our strong liquidity and ability to generate cash, positions us well for the duration of this period and for the long term.”

First Quarter Fiscal 2021 Results

Net sales for the first quarter of fiscal 2021 were $802.6 million, down 5.3%, compared to $847.2 million for the first quarter of the prior fiscal year, as a result of continued COVID-19 related market declines. Organic net sales declined 5.7%.

Year over year sales declines were more pronounced in ceilings and steel framing, as these product categories are tied primarily to commercial construction which remained relatively more challenged than the residential market during the quarter.

Gross profit of $260.5 million decreased 4.8% compared to the first quarter of fiscal 2020 primarily due to lower sales. Gross margin of 32.5% improved 20 basis points year over year as a result of favorable product mix and purchasing initiatives.

Selling, general and administrative (“SG&A”) expense as a percentage of net sales was 22.8% for the quarter compared to 23.0% in the first quarter of fiscal 2020. Adjusted SG&A expense as a percentage of net sales was 22.2% compared to 22.6% in the prior year quarter. This 40 basis point improvement directly resulted from the proactive measures taken to defer or limit non-essential operating and other discretionary expenses and to align the Company’s cost structure with the current demand environment resulting from the COVID-19 pandemic. These benefits were partially offset primarily by deflationary market pricing of certain of the Company’s products.

Net income of $27.2 million, or $0.63 per diluted share, increased 9.7% from $24.8 million, or $0.59 per diluted share, in the first quarter of the prior fiscal year. Adjusted net income of $40.3 million, or $0.94 per diluted share, increased 7.5% from $37.5 million, or $0.89 per diluted share, in the first quarter of the prior fiscal year. Adjusted EBITDA of $83.1 million compared to $83.6 million in the first quarter of the prior fiscal year. Adjusted EBITDA margin of 10.3% improved 40 basis points from 9.9% a year ago.

Balance Sheet and Liquidity

As of July 31, 2020, the Company had cash on hand of $139.7 million and total debt of $1.0 billion. Net debt leverage was 3.0 times as of the end of the quarter compared to 2.9 times as of the end of the fourth quarter of fiscal 2020 and 3.7 times as of the end of the first quarter of fiscal 2020.

As is typical during the Company’s first quarter of the fiscal year, the Company recorded a use of cash from operating activities and free cash flow, which totaled $15.7 million and $20.5 million, respectively, in the first quarter. This compared to a use of cash from operating activities and free cash flow of $12.4 million and $18.3 million, respectively, in the first quarter of the prior fiscal year.

Conference Call and Webcast

GMS will host a conference call and webcast to discuss its results for the first quarter of fiscal 2021 ended July 31, 2020 and other information related to its business at 8:30 a.m. Eastern Time on Thursday, September 3, 2020. Investors who wish to participate in the call should dial 877-407-3982 (domestic) or 201-493-6780 (international) at least 5 minutes prior to the start of the call. The live webcast will be available on the Investors section of the Company’s website at www.gms.com. There will be a slide presentation of the results available on that page of the website as well. Replays of the call will be available through October 3, 2020 and can be accessed at 844-512-2921 (domestic) or 412-317-6671 (international) and entering the pass code 13708456.

About GMS Inc.

Founded in 1971, GMS operates a network of 260 distribution centers across the United States and Canada. GMS’s extensive product offering of wallboard, suspended ceilings systems, or ceilings, and complementary construction products is designed to provide a comprehensive one-stop-shop for our core customer, the interior contractor who installs these products in commercial and residential buildings.

Use of Non-GAAP Financial Measures

GMS reports its financial results in accordance with GAAP. However, it presents Adjusted net income, free cash flow, Adjusted SG&A, Adjusted EBITDA, and Adjusted EBITDA margin, which are not recognized financial measures under GAAP. GMS believes that Adjusted net income, free cash flow, Adjusted SG&A, Adjusted EBITDA and Adjusted EBITDA margin assist investors and analysts in comparing its operating performance across reporting periods on a consistent basis by excluding items that the Company does not believe are indicative of its core operating performance. The Company’s management believes Adjusted net income, Adjusted SG&A, free cash flow, Adjusted EBITDA and Adjusted EBITDA margin are helpful in highlighting trends in its operating results, while other measures can differ significantly depending on long-term strategic decisions regarding capital structure, the tax jurisdictions in which the Company operates and capital investments. In addition, the Company utilizes Adjusted EBITDA in certain calculations under its senior secured asset based revolving credit facility and its senior secured first lien term loan facility.

You are encouraged to evaluate each adjustment and the reasons GMS considers it appropriate for supplemental analysis. In addition, in evaluating Adjusted net income, Adjusted SG&A and Adjusted EBITDA, you should be aware that in the future, the Company may incur expenses similar to the adjustments in the presentation of Adjusted net income, Adjusted SG&A and Adjusted EBITDA. The Company’s presentation of Adjusted net income, Adjusted SG&A, Adjusted SG&A margin, Adjusted EBITDA, and Adjusted EBITDA margin should not be construed as an inference that its future results will be unaffected by unusual or non-recurring items. In addition, Adjusted net income, free cash flow, Adjusted SG&A and Adjusted EBITDA may not be comparable to similarly titled measures used by other companies in GMS’s industry or across different industries. Please see the tables at the end of this release for a reconciliation of Adjusted EBITDA, free cash flow, Adjusted SG&A and Adjusted net income to the most directly comparable GAAP financial measures.

When calculating organic net sales growth, the Company excludes from the calculation (i) net sales of acquired businesses until the first anniversary of the acquisition date, and (ii) the impact of foreign currency translation.

Forward-Looking Statements and Information:

This press release 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,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “might,” “plan,” “potential,” “predict,” “seek,” or “should,” or the negative thereof or other variations thereon or comparable terminology. In particular, statements about the markets in which GMS operates and the economy generally, actions taken to optimize our operations and align our business consistent with demand, our ability to continue successfully navigating the evolving operating environment, strategic initiatives and growth potential across the Company’s business, our efforts in response to COVID-19, and the ability to deliver growth, value creation and long-term success contained in this press release 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 3, 2020. 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 3, 2020.

Contact Information: 

Investors: 

Leslie H. Kratcoski 

ir@gms.com 

770-723-3306

GMS Inc. 

Condensed Consolidated Statements of Operations (Unaudited) 

(in thousands, except per share data)

(1) The following table sets forth the computation of basic and diluted earnings per share of common stock for periods presented:

GMS Inc. 

Condensed Consolidated Balance Sheets (Unaudited) 

(in thousands, except per share data)

GMS Inc. 

Condensed Consolidated Statements of Cash Flows (Unaudited) 

(in thousands)

GMS Inc. 

Net Sales by Product Group (Unaudited) 

(dollars in thousands)

GMS Inc. 

Reconciliation of Net Income to Adjusted EBITDA (Unaudited) 

(in thousands)

GMS Inc. 

Reconciliation of Cash Used In Operating Activities to Free Cash Flow (Unaudited) 

(in thousands)

GMS Inc. 

Reconciliation of Selling, General and Administrative Expense to Adjusted SG&A (Unaudited)

(in thousands)

GMS Inc. 

Reconciliation of Income Before Taxes to Adjusted Net Income (Unaudited) 

(in thousands, except per share data)

Exhibit 99.2

September 3, 2020 Q1 FY 2021 Earnings Conference Call

2 Safe Harbor and Basis of Presentation Forward - Looking Statement 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 “anticip ate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “might,” “plan,” “potential,” “predict,” “seek,” or “should,” or the negative thereof or other variations thereon or comparable terminology. In particular, statements about the markets in which GMS operates and the economy generally, actions taken to op tim ize our operations and align our business consistent with demand, our ability to continue successfully navigating the evolving operating environment, strategi c i nitiatives and growth potential across the Company’s business, our efforts in response to COVID - 19, future financial performance, the ability of the Company to grow strong er, and the ability to deliver growth, value creation and long - term success contained in this presentation may be considered forward - looking statements. The Company ha s based forward - looking statements on its current expectations, assumptions, estimates and projections. While the Company believes these expectations, assumptio ns, 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 unce rtainties, 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 3, 2020. The Company undertakes no obligation to update any of the fo rwa rd - looking statements made herein, whether as a result of new information, future events, changes in expectation or otherwise. These forward - looking statements sho uld not be relied upon as representing the Company’s views as of any date subsequent to September 3, 2020. Use of Non - GAAP and 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 perform anc e 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 und ers tanding 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 o f n et income, diluted earnings per share or net cash provided by (used in) operating activities prepared in accordance with generally accepted accounting principles in the U nit ed 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 dir ectly comparable GAAP measures.

3 Q1 Fiscal 2021 Highlights Q1 results reflect outstanding execution by the entire team against the backdrop of a business environment that remained challenging throughout the period. Net sales decreased 5.3% due to continued COVID - 19 related market declines; Organic net sales were down 5.7%. Despite these top - line challenges, we achieved higher profit margins year over year as a result of proactive and rapid alignment of our cost structure to lower demand, our balanced product and market mix and a relentless focus on serving our customers with operational excellence: Gross margin of 32.5% improved 20 basis points. Net income and adjusted net income (1) up 9.7% and 7.5%, respectively. Adjusted EBITDA margin (1) of 10.3%, up 40 basis points. The health, safety and wellbeing of our employees, business partners and communities remains our top priority. All of us at GMS continue to express our gratitude to all those who have been and continue to be on the frontlines every day during these unprecedented time. (1) For a reconciliation of Adjusted Net Income, Adjusted EBITDA, and Adjusted EBITDA Margin to the most directly comparable GAAP me trics, see Appendix.

4 Q1 Fiscal 2021 Performance Net Sales & Mix $847.2 $802.6 $0 $300 $600 $900 Fiscal Q1 2020 Fiscal Q1 2021 40% 15% 16% 29% ▪ Net sales decline of 5.3% due to continued COVID - 19 related declines in the US, partially offset by higher sales in Canada. ▪ Organic net sales down 5.7%: Net Sales ($ mm) 41% 14% 14% 31% Gross Profit & Margin $273.7 $260.5 32.3% 32.5% 20.0% 20.5% 21.0% 21.5% 22.0% 22.5% 23.0% 23.5% 24.0% 24.5% 25.0% 25.5% 26.0% 26.5% 27.0% 27.5% 28.0% 28.5% 29.0% 29.5% 30.0% 30.5% 31.0% 31.5% 32.0% 32.5% 33.0% 33.5% $0 $50 $100 $150 $200 $250 $300 Fiscal Q1 2020 Fiscal Q1 2021 Gross Profit Gross Margin ▪ Gross Profit declined 4.8% primarily due to lower sales. ▪ Gross margin of 32.5% improved 20 basis points from as result of favorable product mix and purchasing initiatives. Total Volume Price/Mix Wallboard -4.1% -1.3% -2.8% Ceilings -12.5% -11.7% -0.8% Steel -16.4% -10.7% -5.7% Other +1.5% Organic Growth

5 SG&A and Adjusted SG&A (1) Q1 Fiscal 2021 Performance ▪ Reported SG&A was 22.8% of sales compared to 23.0% of sales a year ago. ▪ Adjusted SG&A (1) was 22.2% of sales compared to 22.6% of sales a year ago. ▪ Adjusted SG&A as % of sales improved by 40 bps year over year despite 50 basis points of negative impact deflationary market pricing of certain of products. Approximately 90 basis points of improvement directly resulted from proactive measures taken to align the Company’s cost structure with the current demand environment resulting from the COVID - 19 pandemic. Adj. SG&A ($ mm) 7.9% 9.4% (1) For a reconciliation of Adjusted SG&A, Adjusted Net Income, Adjusted EBITDA and Adjusted EBITDA Margin to the most directly c omp arable GAAP metrics, see Appendix. $191.1 $178.1 22.6% 22.2% 20.0% 20.5% 21.0% 21.5% 22.0% 22.5% 23.0% $0 $50 $100 $150 $200 Fiscal Q1 2020 Fiscal Q1 2021 Adj. SG&A Adj. SG&A % Net Income (Loss), Adjusted Net Income & Adjusted EBITDA (1) ▪ Reported net income of $27.2 million increased 9.7% year over year. ▪ Adjusted net income (1) of $40.3 million increased 7.5% year over year. ▪ Adjusted EBITDA (1) of $83.1 million declined only slightly from $83.6 million a year ago. ▪ Adjusted EBITDA margin (1) of 10.3% improved 40 basis points year over year, resulting in a decremental Adjusted EBITDA margin of 1.4%. $83.6 $83.1 9.9% 10.3% 5.0% 5.5% 6.0% 6.5% 7.0% 7.5% 8.0% 8.5% 9.0% 9.5% 10.0% 10.5% $0 $25 $50 $75 Fiscal Q1 2020 Fiscal Q1 2021 Adj. EBITDA Adj. EBITDA Margin Adj. EBITDA ($ mm)

6 Cash Flow, Liquidity and Net Leverage ▪ As is typical during the first quarter of the fiscal year, we recorded a use of cash from operating activities and free cash flow. ▪ Substantial liquidity, with $139.7 million of cash on hand and an additional $372.5 million available under our revolving credit facilities as of 7/31/2020. ▪ Repaid ~$44 million of ~$87 million proactively drawn on revolving credit facilities in late March as potential disruptions in the credit markets did not materialize. Leverage Summary LTM Net Debt / PF Adjusted EBITDA (2) (1) For a reconciliation of free cash flow to cash provided by operating activities, the most directly comparable GAAP metric, se e A ppendix. (2) For a reconciliation Pro Forma Adjusted EBITDA to net income, the most directly comparable GAAP metric, see Appendix. (3) Net of unamortized discount of $2.1mm, $2.0mm, $1.9mm, $1.8mm and $1.5 mm as of July 31, 2019, October 31, 2019, January 31,2 020 , April 30, 2020, and July 31, 2020 respectively. (4) Net of deferred financing costs of $11.6mm, $10.5mm, $10.0 mm, $9.0 mm and $8.5 mm as of July 31, 2019, October 31, 2019, Jan uar y 31,2020, April 30, 2020, and July 31, 2020 respectively. (5) Net of unamortized discount of $1.1mm, $1.3mm, $1.2mm, $1.1 mm and $1.0mm as of July 31, 2019, October 31, 2019, January 31, 202 0, April 30, 2020, and July 31, 2020 respectively. Use of Cash from Operations and Free Cash Flow (1) 3.7 x 3.5 x 3.3 x 2.9 x 3.0 x 7/31/19 10/31/19 1/31/20 4/30/20 7/31/20 ($ mm) 7/31/19 10/31/19 1/31/20 4/30/20 7/31/20 LTM LTM LTM LTM LTM Cash and cash equivalents $24 $36 $41 $211 $140 Asset-Based Revolver $54 $48 $10 $87 $44 First Lien Term Loan (3)(4) 971 920 918 866 864 Capital Lease Obligations 114 117 126 129 123 Installment Notes & Other (5) 22 16 16 15 13 Total Debt $1,161 $1,100 $1,069 $1,097 $1,045 Total Net Debt $1,137 $1,064 $1,028 $887 $905 PF Adj. EBITDA (2) $305 $308 $311 $302 $300 Total Debt / PF Adj. EBITDA 3.8x 3.6x 3.4x 3.6x 3.5x Net Debt / PF Adj. EBITDA 3.7x 3.5x 3.3x 2.9x 3.0x $ mm Q1 2020 Q1 2021 Cash Used in Operations (12.4)$ (15.7)$ Capital Expenditures (5.9)$ (4.7)$ Use of Free Cash (18.3)$ (20.5)$

7 Expand Share in Core Products Grow Other Products Platform Expansion Capitalize on existing fixed investment in locations and equipment where we’re underpenetrated or below expected share Grow select “Other Product” opportunities outside of core products to diversify and profitably expand our product offering Expand the platform through accretive acquisition and greenfield opportunities, balanced with debt reduction priorities Strategic Growth Priorities Profitability Leverage our scale and employ technology and best practices to deliver further margin expansion

8 GMS is Well - Positioned Both Now and for the Long - Term • Our team intends to quickly and nimbly address challenges and leverage opportunities arising from the continued uncertainty regarding the near - term outlook for the industry and the broader economy. • Strong cash flow generation resulting from defensive nature of business model and tight management of working capital. • Healthy balance sheet and strong liquidity position. • A North American market leader in specialty distribution of interior construction products. • Significant scale combined with local expertise. • Differentiated service model. • Entrepreneurial culture. • Executing on strategic priorities to capitalize on long - term growth opportunities.

Appendix

10 Summary Quarterly Financials (In millions, except per share data) 1Q20 2Q20 3Q20 4Q20 FY20 1Q21 (Unaudited) Wallboard Volume (MSF) 1,064 1,103 993 1,029 4,189 1,054 Wallboard Price ($ / '000 Sq. Ft.) 321$ 318$ 317$ 314$ 317$ 311$ Wallboard 342$ 351$ 314$ 323$ 1,330$ 328$ Ceilings 129 123 113 111 476 114 Steel framing 132 136 119 115 502 110 Other products 245 252 215 221 934 250 Net sales 847 862 761 771 3,241 803 Cost of sales 574 577 508 519 2,178 542 Gross profit 274 284 253 252 1,063 260 Gross margin 32.3% 33.0% 33.3% 32.6% 32.8% 32.5% Operating expenses: Selling, general and administrative expenses 195 200 193 196 784 183 Depreciation and amortization 29 30 29 28 117 27 Impairment of goodwill - - - 63 63 - Total operating expenses 224 230 223 287 964 210 Operating income (loss) 50 55 31 (35) 100 50 Other (expense) income: Interest expense (18) (18) (16) (15) (68) (14) Gain on legal settlement - - - 14 14 - Write-off of discount and deferred financing costs - (1) - (1) (1) - Other income, net 1 1 (0) 1 2 1 Total other expense, net (17) (17) (17) (1) (53) (13) Income (loss) from continuing operations, before tax 32 37 14 (37) 46 37 Income tax expense 8 8 3 5 23 10 Net income (loss) 25$ 29$ 11$ (41)$ 23$ 27$ Business Days 64 65 62 64 255 64 Net Sales by Business Day 13.2$ 13.3$ 12.3$ 12.0$ 12.7$ 12.5$ Beginning Branch Count 254 259 259 262 254 264 Added Branches 5 - 3 2 10 (3) Ending Branch Count 259 259 262 264 264 261

11 Quarterly Cash Flows (1) Free cash flow is a non - GAAP financial measure defined as net cash provided by (used in) operations less capital expenditures. D ifferences may occur due to rounding. ($ in millions) (Unaudited) 1Q20 2Q20 3Q20 4Q20 FY20 1Q21 Net income (loss) $ 24.8 $ 29.1 $ 10.9 $ (41.5) $ 23.4 $ 24.8 Non-cash changes & other changes (4.5) 54.1 34.5 118.5 202.6 2.4 Changes in primary working capital components: Trade accounts and notes receivable (23.2) (6.7) 46.5 24.9 41.4 (23.0) Inventories 0.0 1.8 (1.5) (4.9) (4.6) 14.0 Accounts payable (9.5) 4.0 (24.9) 70.7 40.3 (33.9) Cash provided by (used in) operating activities (12.4) 82.4 65.4 167.7 303.1 (15.7) Purchases of property and equipment (5.9) (8.7) (6.2) (4.3) (25.2) (4.7) Proceeds from sale of assets 0.2 0.8 0.2 0.9 2.2 0.3 Acquisitions of businesses, net of cash acquired (10.6) - (10.2) (3.3) (24.1) (0.2) Cash (used in) investing activities (16.3) (7.9) (16.2) (6.7) (47.1) (4.6) Cash provided by (used in) financing activities 5.3 (62.4) (44.4) 10.0 (91.3) (51.8) Effect of exchange rates 0.2 0.1 (0.2) (1.1) (1.1) 0.9 Increase (decrease) in cash and cash equivalents (23.2) 12.1 4.7 170.0 163.6 (71.2) Balance, beginning of period 47.3 24.1 36.3 40.9 47.3 210.9 Balance, end of period $ 24.1 $ 36.3 $ 40.9 $ 210.9 $ 210.9 $ 139.7 Supplemental cash flow disclosures: Cash paid for income taxes $ 18.8 $ 6.9 $ 4.6 $ 1.3 $ 31.5 $ 3.5 Cash paid for interest $ 17.0 $ 16.6 $ 15.6 $ 14.5 $ 63.7 $ 13.1 Cash provided by (used in) operating activities $ (12.4) $ 82.4 $ 65.4 $ 167.7 $ 303.1 $ (15.7) Purchases of property and equipment (5.9) (8.7) (6.2) (4.3) (25.2) (4.7) Free cash flow (1) (18.3) 73.6 59.2 163.4 277.9 (20.5)

12 Q1 2021 Net Sales (1) Organic net sales growth calculation excludes net sales of acquired businesses until first anniversary of acquisition date an d i mpact of foreign currency translation. ($ in millions) (Unaudited) FY21 FY20 Reported Organic (1) Organic (1) 799.2$ 847.2$ Acquisitions 6.9 - Fx Impact (3.5) - Total Net Sales 802.6$ 847.2$ (5.3%) (5.7%) Wallboard 328.0$ 341.6$ (4.0%) (4.1%) Ceilings 113.7 129.1 (11.9%) (12.5%) Steel Framing 110.5 131.8 (16.2%) (16.4%) Other Products 250.4 244.6 2.3% 1.5% Total Net Sales 802.6$ 847.2$ (5.3%) (5.7%) Fiscal Q1 Variance

13 Quarterly Net Income to Adjusted EBITDA Reconciliation Commentary A. Represents non - cash expense related to stock appreciation rights agreements B. Represents non - cash compensation expense related to changes in the values of noncontrolling interests C. Represents non - cash equity - based compensation expense related to the issuance of share - based awards D. Represents severance expenses and other costs permitted in calculations under the ABL Facility and the First Lien Facility E. Represents one - time costs related to acquisitions paid to third parties F. Includes impairment of assets resulting from restructuring plans to close certain facilities and gains from the sale of assets. G. Represents the non - cash cost of sales impact of purchase accounting adjustments to increase inventory to its estimated fair value H. Represents one - time costs related to our secondary offerings paid to third party advisors ( $ in 000s) 1Q20 2Q20 3Q20 4Q20 FY20 1Q21 (Unaudited) Net Income (Loss) 24,820$ 29,138$ 10,879$ (41,456)$ 23,381$ 27,219$ Add: Interest Expense 18,277 17,559 16,474 15,408 67,718 14,081 Add: Write off of debt discount and deferred financing fees - 707 - 624 1,331 - Less: Interest Income (12) (6) (8) (62) (88) (37) Add: Income Tax Expense 7,590 7,927 2,816 4,611 22,944 9,604 Add: Depreciation Expense 12,422 12,592 12,930 13,388 51,332 12,827 Add: Amortization Expense 16,853 16,926 16,492 14,930 65,201 14,270 EBITDA 79,950$ 84,843$ 59,583$ 7,443$ 231,819$ 77,964$ Adjustments Impairment of goodwill - - - 63,074 63,074 - Stock appreciation rights expense (A) 60 1,267 (347) 592 1,572 792 Redeemable noncontrolling interests (B) 662 (18) (318) 194 520 252 Equity-based compensation (C) 1,395 2,315 1,465 1,885 7,060 1,605 Severance and other permitted costs (D) 554 1,394 1,700 2,085 5,733 1,947 Transaction costs (acquisition and other) (E) 972 327 434 681 2,414 100 (Gain) loss on disposal of assets (F) (156) (586) (130) 1,530 658 394 Effects of fair value adjustments to inventory (G) 151 - 310 114 575 - Gain on legal settlement - - - (14,029) (14,029) - Secondary public offerings (H) - 363 - - 363 - Total Add-Backs 3,638$ 5,062$ 3,114$ 56,126$ 67,940$ 5,090$ Adjusted EBITDA (as reported) 83,588$ 89,905$ 62,697$ 63,569$ 299,759$ 83,054$

14 Net Income to Pro Forma Adjusted EBITDA Reconciliation Commentary A. Represents non - cash expense related to stock appreciation rights agreements B. Represents non - cash compensation expense related to changes in the values of noncontrolling interests C. Represents non - cash equity - based compensation expense related to the issuance of share - based awards D. Represents severance expenses and other costs permitted in calculations under the ABL Facility and the First Lien Facility E. Represents one - time costs related to our initial public offering and acquisitions paid to third party advisors as well as costs related to the retirement of corporate stock appreciation rights F. Represents management fees paid to AEA, which were discontinued after the IPO G. Represents the non - cash cost of sales impact of purchase accounting adjustments to increase inventory to its estimated fair value H. Represents mark - to - market adjustments for derivative financial instruments I. Represents one - time costs related to our secondary offerings paid to third party advisors J. Represents expenses paid to third party advisors related to debt refinancing activities K. Pro forma impact of earnings from acquisitions from the beginning of the LTM period to the date of acquisition, including synergies ( $ in 000s) 1Q21 LTM 2020 2019 2018 2017 2016 (Unaudited) Net Income 25,780$ 23,381$ 56,002$ 62,971$ 48,886$ $ 12,564 Add: Interest Expense 63,522 67,718 73,677 31,395 29,360 37,418 Add: Write off of debt discount and deferred financing fees 1,331 1,331 - 74 7,103 - Less: Interest Income (113) (88) (66) (177) (152) (928) Add: Income Tax Expense 24,958 22,944 14,039 20,883 22,654 12,584 Add: Depreciation Expense 51,737 51,332 46,456 24,075 25,565 26,667 Add: Amortization Expense 62,618 65,201 71,003 41,455 43,675 37,548 EBITDA 229,833$ 231,819$ 261,111$ 180,676$ 177,091$ $ 125,853 Adjustments Impairment of goodwill 63,074 63,074 - - - - Stock appreciation rights expense (A) 2,304 1,572 2,730 2,318 148 1,988 Redeemable noncontrolling interests (B) 110 520 1,188 1,868 3,536 880 Equity-based compensation (C) 7,270 7,060 3,906 1,695 2,534 2,699 Severance and other permitted costs (D) 7,126 5,733 8,152 581 (157) 379 Transaction costs (acquisition and other) (E) 1,542 2,414 7,858 3,370 2,249 3,751 (Loss) gain on disposal of assets 1,208 658 (525) (509) (338) (645) AEA management fee (F) - - - - 188 2,250 Effects of fair value adjustments to inventory (G) 424 575 4,176 324 946 1,009 Gain on legal settlement (14,029) (14,029) - - - - Change in fair value of financial instruments (H) - - 6,395 6,125 382 - Secondary public offerings (I) 363 363 - 1,525 1,385 19 Debt transaction costs (J) - - 678 1,285 265 - Total Add-Backs 69,392$ 67,940$ 34,558$ 18,582$ 11,138$ 36,898$ Adjusted EBITDA (as reported) 299,225$ 299,759$ 295,669$ 199,258$ 188,229$ 162,751$ Contributions from acquisitions (K) 776 1,480 6,717 1,280 9,500 12,093 Pro Forma Adjusted EBITDA 300,001$ 301,239$ 302,386$ 200,538$ 197,729$ 174,844$

15 Reconciliation of Income Before Taxes to Adjusted Net Income Reconciliation Commentary A. Depreciation and amortization from the increase in value of certain long - term assets associated with the April 1, 2014 acquisition of the predecessor company and the acquisition of Titan. B. Normalized cash tax rate determined based on our estimated taxes excluding the impact of purchase accounting and certain other deferred tax amounts. C. Diluted shares outstanding for periods prior to June 13, 2019 have been adjusted to include the effect of 1.1 million shares of equity issued in connection with the acquisition of Titan that were exchangeable for the Company’s common stock. On June 13, 2019, the holders exchanged all of the exchangeable shares for 1.1 million shares of the Company’s common stock. ($ in 000s) 1Q21 1Q20 (Unaudited) Income before taxes 36,823$ 32,410$ EBITDA add-backs 5,090 3,638 Purchase accounting depreciation and amortization (A) 10,135 12,385 Adjusted pre-tax income 52,048 48,433 Adjusted income tax expense 11,711 10,897 Adjusted net income 40,337$ 37,535$ Effective tax rate (B) 22.5% 22.5% Weighted average shares outstanding: Basic 42,624 41,001 Diluted (C) 43,017 42,148 Adjusted net income per share: Basic 0.95$ 0.92$ Diluted 0.94$ 0.89$

16 Reported SG&A to Adjusted SG&A Reconciliation Commentary A. Represents non - cash expense related to stock appreciation rights agreements B. Represents non - cash compensation expense related to changes in the values of noncontrolling interests C. Represents non - cash equity - based compensation expense related to the issuance of share - based awards D. Represents severance expenses and other costs permitted in calculations under the ABL Facility and the First Lien Facility E. Represents one - time costs related to acquisitions paid to third parties. F. Represents one - time costs related to our secondary offerings paid to third party advisors (Unaudited) 1Q20 2Q20 3Q20 4Q20 FY2020 1Q21 ($ in millions) SG&A - Reported 194.6$ 200.5$ 193.4$ 195.6$ 784.1$ 183.1$ Adjustments Stock appreciation rights expense (A) (0.1) (1.3) 0.3 (0.6) (1.6) (0.8) Redeemable noncontrolling interests (B) (0.7) 0.0 0.3 (0.2) (0.5) (0.3) Equity-based compensation (C) (1.4) (2.3) (1.5) (1.9) (7.1) (1.6) Severance and other permitted costs (D) (0.6) (1.4) (0.5) (1.9) (4.3) (1.9) Transaction costs (acquisition and other)(E) (1.0) (0.3) (0.4) (0.7) (2.4) (0.1) Gain on disposal of assets 0.2 0.6 0.1 (1.5) (0.7) (0.4) Secondary public offerings (F) - (0.4) - - (0.4) - SG&A - Adjusted 191.1$ 195.4$ 191.8$ 188.9$ 767.2$ 178.1$ % of net sales 22.6% 22.7% 25.2% 24.5% 23.7% 22.2%

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