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EXHIBIT 4

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

        We consent to the use of our reports dated March 6, 2019 relating to the combined financial statements of Granite REIT Inc. and Granite Real Estate Investment Trust and subsidiaries (collectively, the "Trust") and the effectiveness of the Trust's internal control over financial reporting appearing in this Annual Report on Form 40-F for the year ended December 31, 2018.

Toronto, Canada
March 6, 2019 /s/ Deloitte LLP
Deloitte LLP
Chartered Professional Accountants,
Licensed Public Accountants

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EXHIBIT 4

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM