Exhibit 99.1

Summit Materials Announces Second Quarter 2016 Results

Denver, Colorado (August 3, 2016) — Summit Materials, Inc. (NYSE: SUM, “Summit” or the “Company”), a leading vertically integrated construction materials company, announces results for the second quarter of 2016. The Company has posted supplementary materials to its investor relations website.

Highlights – Second Quarter 2016 Compared to Second Quarter 2015:

Tom Hill, CEO of Summit, stated, “We’ve made considerable progress over the past year integrating acquisitions, which contributed significantly to our net revenue and Adjusted EBITDA growth in the second quarter of 2016. Our materials-based growth strategy was evident with higher aggregates and cement exposure benefitting our overall gross margin performance. In cement, the successful integration of Davenport helped more than double Cement segment Adjusted EBITDA.  The positive cement market fundamentals in the Mississippi river region resulted in both volume and price improvements. The Boxley, AMC and Sierra acquisitions completed during the year have all exceeded expectations and expanded our geographic footprint into several high growth markets. In our legacy businesses, we were pleased to achieve another quarter of organic price growth across all lines of business, including aggregates up 6.7%, helped by our effective price optimization focus. We experienced strong activity in North Texas highway demand and overall improvement in Utah, Kansas and Missouri. That said, organic volumes were softer overall due to wet weather, especially in Texas, lower aggregates volume in Vancouver with the completion of a large sand river project in 2015 and some competitive pressure in Austin, Texas. We expect all three of these factors to improve in the second half of the year as we make additional progress to grow our company. Moving forward in 2016, we are firmly situated to achieve our Adjusted EBITDA goals for the full year.”

Brian Harris, CFO of Summit, said, “We ended the second quarter with net leverage of 4.5x primarily reflecting the 46.8% increase in Adjusted EBITDA year-over-year. We were pleased to achieve this while funding two bolt-on transactions during the quarter and surpassing our targeted $30 million of annualized acquired Adjusted EBITDA. Our capital investments in our announced aggregates facility enhancement initiatives are also moving forward on schedule

and on budget. With the continuation of strong results from our materials based-strategy along with ample liquidity on our balance sheet, we have the flexibility to pursue our strategy of acquiring attractively positioned reserves in attractive markets with selective downstream exposure, while maintaining our commitment to reduce our leverage ratios by year end.”

Second Quarter 2016 Operating Results

In the second quarter of 2016, net revenue increased 25.4% to $412.6 million, compared to $329.0 million in the prior year quarter. The improvement in net revenue was primarily attributable to an increase in volumes across all lines of business and higher prices in aggregates, cement and asphalt. Net revenue growth from acquisitions in the West and East segments was $56.5 million compared to the prior year quarter.

Adjusted EBITDA grew 46.8% to $114.7 million, compared to $78.1 million in the prior year quarter, with growth in all operating segments. As a percentage of net revenue, Adjusted EBITDA improved to 27.8%, up 400 basis points from the prior year quarter. Adjusted EBITDA by segment in the second quarter of 2016 compared to the prior year quarter was as follows:

Gross profit increased 38.3% to $160.1 million, compared to $115.8 million in the prior year quarter. As a percentage of net revenue, gross margin improved to 38.8%, compared to 35.2% in the prior year quarter, primarily attributable to a higher percentage of revenue from materials and cost saving initiatives.  

In the second quarter of 2016, net income attributable to Summit Materials, Inc. was $13.4 million, and basic EPS was $0.22 per share of Class A common stock. The shares of Class A common stock are issued by Summit Materials, Inc., and as such the earnings and equity interests of noncontrolling interests, including LP units, are not included in basic earnings per share.

Adjusted net income was $46.2 million and Adjusted EPS was $0.46 per diluted share. Summit believes adjusted net income and Adjusted EPS are more representative of earnings performance, because these measures exclude the non-operating impact to earnings per share of any potential conversions of LP units to Class A common stock in any given quarter. 

Acquisitions

In April 2016, Summit acquired Sierra Ready Mix, (“Sierra”), a vertically integrated aggregates and ready-mixed concrete business located in Las Vegas, Nevada.  Sierra is a well-established aggregates and ready mix concrete supplier in the Las Vegas market with an excellent reputation for quality and service. Sierra operates a sand & gravel pit and two ready-mixed concrete facilities and has well-balanced exposure across all end-use segments. The acquisition provides Summit with premier, well-located assets in an expanding market.

In May 2016, Summit acquired seven aggregates quarries in central and northwest Missouri from Oldcastle Materials. These quarries added over 100 million tons of permitted reserves, primarily serving infrastructure and nonresidential demand, which enhances the scale and aggregate reserves position of Summit’s existing presence in Missouri.

Liquidity and Capital Resources

At July 2, 2016, the Company had cash of $9.2 million, total outstanding debt of $1,537.2 million and a borrowing capacity of $195.4 million. Our borrowing capacity is net of $25.6 million outstanding letters of credit and $14.0 million of outstanding borrowings under the revolving credit facility.

Full Year 2016 Outlook

For the full year 2016, based on current market conditions, Summit expects to generate Adjusted EBITDA in the range of $360.0 million to $370.0 million, compared to Adjusted EBITDA of $287.5 million in 2015. The Adjusted EBITDA outlook assumes organic improvement, along with the successor period for acquisitions completed through today’s date.

Summit continues to target approximately $30.0 million of annualized Adjusted EBITDA per year from acquisitions. The upwardly revised full year 2016 Adjusted EBITDA outlook range of $360.0 million to $370.0 million excludes the potential upside from any future acquisitions due to the unspecified closing dates of any future acquisitions, the timing of which will impact the magnitude of acquired Adjusted EBITDA realized in 2016.

Webcast and Conference Call Information

Summit will conduct a conference call at 11:00 a.m. Eastern Time (9:00 a.m. Mountain Time) on Wednesday, August 3, 2016 to review second quarter 2016 results, discuss recent events, and conduct a question-and-answer period. A webcast of the conference call and presentation slides to be referred to on the call will be available in the Investors section of Summit’s website at investors.summit-materials.com. To listen to a live broadcast, go to the site at least 15 minutes prior to the scheduled start time in order to register, download, and install any necessary audio software.

To participate in the telephone conference call:

To listen to a replay of the telephone conference call:

About Summit Materials

Summit Materials is a leading vertically integrated materials-based company that supplies aggregates, cement, ready-mixed concrete and asphalt in the United States and British Columbia, Canada. Summit is a geographically diverse, materials-based business of scale that offers customers a single-source provider of construction materials and related downstream products in the public infrastructure, residential and nonresidential, and end markets. Summit has a strong track record of successful acquisitions since its founding and continues to pursue growth opportunities in new and existing markets.

For more information about Summit Materials, please visit www.summit-materials.com.  

Non-GAAP Financial Measures

The Securities and Exchange Commission (“SEC”) regulates the use of “non-GAAP financial measures,” such as adjusted net income, Adjusted EPS, Adjusted EBITDA, gross profit and free cash outflow, which are derived on the basis of methodologies other than in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”). We have provided these measures because, among other things, we believe that they provide investors with additional information to measure our performance, evaluate our ability to service our debt and evaluate certain flexibility under our restrictive covenants. Our adjusted net income, Adjusted EPS, Adjusted EBITDA, gross profit and free cash outflow, may vary from the use of such terms by others and should not be considered as alternatives to or more important than net income (loss), operating income (loss), revenue or any other performance measures derived in accordance with U.S. GAAP as measures of operating performance or to cash flows as measures of liquidity.

Adjusted EBITDA and other non-GAAP measures have important limitations as analytical tools, and you should not consider them in isolation or as substitutes for analysis of our results as reported under U.S. GAAP. Some of the limitations of Adjusted EBITDA are that these measures do not reflect: (i) our cash expenditures or future requirements for capital expenditures or contractual commitments; (ii) changes in, or cash requirements for, our working capital needs; (iii) interest expense or cash requirements necessary to service interest and principal payments on our debt; and (iv) income tax payments we are required to make. Because of these limitations, we rely primarily on our U.S. GAAP results and use Adjusted EBITDA and other non-GAAP measures only supplementally.

Adjusted EBITDA, gross profit, adjusted net income, Adjusted EPS and free cash outflow reflect an additional way of viewing aspects of our business that, when viewed with our GAAP results and the accompanying reconciliations to U.S. GAAP financial measures included in the tables attached to this press release, may provide a more complete understanding of factors and trends affecting our business. We strongly encourage investors to review our consolidated financial statements in their entirety and not rely on any single financial measure.

Reconciliations of the non-GAAP measures used in this press release are included in the attached tables, to the extent available without unreasonable effort. 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-looking non-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.

Cautionary Statement Regarding Forward-Looking Statements

This press release contains “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,” “should,” “seeks,” “intends,” “trends,” “plans,” “estimates,” “projects” or “anticipates” or similar expressions that concern our strategy, plans, expectations or intentions. Any and all statements made relating to the expectations for our anticipated benefits from recent acquisitions, the macroeconomic outlook for our markets, potential acquisition activity, our estimated and projected earnings, margins, costs, expenditures, cash flows, sales volumes and financial results are forward-looking statements. These forward-looking statements are subject to risks and uncertainties that may change at any time, and, therefore, our actual results may differ materially from those expected. 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 impact 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 achieved. 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 our Annual Report on Form 10-K for the fiscal year ended January 2, 2016. Such factors may be updated from time to time in our periodic filings with the SEC, which are accessible on the SEC’s website at www.sec.gov.

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 otherwise required by law.

SUMMIT MATERIALS, INC. AND SUBSIDIARIES

Unaudited Consolidated Statements of Operations

($ in thousands, except share and per share amounts)

SUMMIT MATERIALS, INC. AND SUBSIDIARIES

Consolidated Balance Sheets

($ in thousands, except share and per share amounts)

SUMMIT MATERIALS, INC. AND SUBSIDIARIES

Unaudited Consolidated Statements of Cash Flows

($ in thousands)

SUMMIT MATERIALS, INC. AND SUBSIDIARIES

Unaudited Revenue Data by Segment and Line of Business

($ in thousands)

SUMMIT MATERIALS, INC. AND SUBSIDIARIES

Unaudited Volume and Price Statistics

(Units in thousands)

*     The Davenport Assets were immediately integrated with our existing cement operations such that it is impracticable to bifurcate the growth attributable to the Davenport Assets from organic growth. 

SUMMIT MATERIALS, INC. AND SUBSIDIARIES

Unaudited Reconciliations of Gross Revenue to Net Revenue by Line of Business

($ and Units in thousands)

SUMMIT MATERIALS, INC. AND SUBSIDIARIES

Unaudited Reconciliations of Non-GAAP Financial Measures

($ in thousands, except share and per share amounts)

The tables below reconcile our net income (loss) to Adjusted EBITDA and present Adjusted EBITDA by segment for the three and six months ended July 2, 2016 and June 27, 2015.

The table below reconciles our net income (loss) per share attributable to Summit Materials, Inc. to adjusted income (loss) per share for the three and six months ended July 2, 2016 and June 27, 2015. The per share amount of the net income (loss) attributable to Summit Materials, Inc. presented in the table is calculated using the total equity interests for the purpose of reconciling to adjusted net income (loss) per share.

The following table reconciles operating income (loss) to gross profit for the three and six months ended July 2, 2016 and June 27, 2015.

The following table reconciles net cash used for operating activities to free cash outflow for the three and six months ended July 2, 2016 and June 27, 2015.