Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in the registration statements (Nos. 333-258487, 333-202669, 333-210036 and 333-235820) on Forms S-8 and S-3 of our reports dated February 24, 2022, with respect to the consolidated financial statements of Summit Materials, Inc. and the effectiveness of internal control over financial reporting.

                                /s/ KPMG LLP

Denver, Colorado

February 24, 2022