November 3, 2021, Toronto, Ontario, Canada — Granite Real Estate Investment Trust and Granite REIT Inc. (TSX: GRT.UN; NYSE: GRP.U) (“Granite” or the “Trust”) announced today the establishment of a $250 million at-the- market equity distribution program (the “ATM Program”).

On November 3, 2021, Granite is filing a prospectus supplement (the “Prospectus Supplement”) to the Trust’s base shelf prospectus dated October 1, 2021 to establish the ATM Program in each of the provinces and territories of Canada, that allows it to issue and sell, at its discretion, up to $250.0 million of stapled units to the public, from time to time. Stapled units sold under the ATM Program will be sold at the prevailing market prices at the time of sale when issued, directly through the facilities of the Toronto Stock Exchange (“TSX”) or any other recognized marketplace upon which the stapled units are listed or quoted or where the stapled units are traded in Canada. Distributions of stapled units by Granite under the ATM Program, if any, will be made in accordance with the terms of the equity distribution agreement dated November 3, 2021 (the “Distribution Agreement”) among Granite, BMO Nesbitt Burns Inc., Scotia Capital Inc. and TD Securities Inc. (collectively, the “Agents”). The ATM Program will be effective until November 1, 2023, unless previously terminated in accordance with the terms of the Distribution Agreement. Sales of stapled units, if any, will be made through “at-the- market distributions” as defined in National Instrument 44-102 – Shelf Distributions. Granite intends to use the net proceeds from the ATM Program, if any, to fund potential future acquisitions, development activity, and for general trust purposes. The TSX has conditionally approved the listing of the stapled units that may be sold under the ATM Program, if any, and Granite has applied to list such stapled units on the New York Stock Exchange.

The Prospectus Supplement contains important detailed information about the stapled units being offered and should be reviewed before any investment decision is made. The Prospectus Supplement, along with the Canadian Shelf Prospectus and Distribution Agreement, are available on SEDAR at www.sedar.com. In addition, Granite will file with the U.S. Securities and Exchange Commission (the “SEC”) a prospectus supplement (the “U.S. Prospectus Supplement”) to its base shelf prospectus included in its registration statement on Form F-10, each of which will be available on EDGAR at www.sec.gov. Alternatively, the Agents will provide the Prospectus Supplement or the U.S. Prospectus Supplement (together with the applicable base shelf prospectus) upon request by contacting: (i) in Canada: BMO Nesbitt Burns Inc., attn: Brampton Distribution Centre C/O The DATA Group of Companies, 9195 Torbram Road, Brampton, Ontario, L6S 6H2, by email at torbramwarehouse@datagroup.ca or by phone at 905-791-3151 Ext. 4312, Scotia Capital Inc., attn: Equity Capital Markets, Scotia Plaza, 64th Floor, 40 King Street West, Toronto, Ontario, M5H 3Y2, by email at equityprospectus@scotiabank.com or by phone at 1-416-863-7704, TD Securities Inc., attn: Symcor, NPM, 1625 Tech Avenue, Mississauga, Ontario, L4W 5P5, by email at sdcconfirms@td.com or by phone at 289-360- 2009 and (ii) in the United States.: BMO Capital Markets Corp., attn: Equity Syndicate Department, 3 Times Square, 25th Floor, New York, NY, 10036, by email at bmoprospectus@bmo.com or by phone at 1-800-414-3627, Scotia Capital (USA) Inc., attn: Equity Capital Markets, 250 Vesey Street, 24th Floor, New York, New York, 10281, by email at equityprospectus@scotiabank.com or by phone at 1-212-225-6853 or TD Securities (USA) LLC, attn: Equity Capital Markets, 1 Vanderbilt Avenue, New York, New York, 10017 or by email at USTMG@tdsecurities.com.